Preparation method of weather-resistant waterborne polyurethane waterproof agent

Abstract

The invention relates to the technical field of waterproof agents, in particular to a preparation method of a weather-resistant waterborne polyurethane waterproof agent, which comprises the following steps: mixing a plurality of materials with a polyesteramine prepolymer solution, and then carrying out polymerization reaction to obtain a waterborne polyurethane solution; the preparation method comprises the following steps: mixing a plurality of raw materials in a reaction kettle to obtain a mixed solution, and carrying out condensation reaction on the mixed solution to obtain a modified nano imosa solution; blending the modified nano imosa solution with the waterborne polyurethane solution with a qualified dispersion state to obtain a reaction solution, and carrying out cross-linking reaction on the reaction solution to obtain the waterborne polyurethane waterproof agent, carrying out vacuum degassing treatment on the waterborne polyurethane waterproof agent to obtain the weather-resistant waterborne polyurethane waterproof agent, and determining the qualification of the weather resistance of the weather-resistant waterborne polyurethane waterproof agent based on the bubble evaluation value of the vacuum degassing treatment of the waterborne polyurethane waterproof agent. The weather resistance of the waterborne polyurethane waterproof agent is improved.

Description

Technical Field

[0001] The invention relates to the technical field of waterproofing agents, and in particular to a method for preparing a weather-resistant waterborne polyurethane waterproofing agent. Background Art

[0002] Weather-resistant water-based polyurethane waterproofing agent is an environmentally friendly waterproof material that uses water as a solvent, is non-toxic and pollution-free, and has good flexibility and adhesion. This material can adapt to the deformation of the substrate and has excellent weather resistance, and can effectively resist the erosion of ultraviolet rays and chemical media. Due to its excellent comprehensive performance, it replaces traditional solvent-based products in applications such as building waterproofing and fabric coatings, providing a safer and more durable waterproofing solution.

[0003] Chinese patent application publication number: CN118221903A discloses a weather-resistant polyurethane waterproofing agent and a preparation method thereof, comprising the following raw materials in parts by weight: 4-10 parts of diisocyanate; 12-15 parts of diol; 3-8 parts of acrylate; 1.2-2.5 parts of chain extender; 0.02-0.05 parts of catalyst; 0.5-1 parts of neutralizer; 2-4 parts of end-capping agent; 1-3 parts of nanocellulose whisker; 60-70 parts of deionized water. However, the prior art has the following problems: the prior art does not analyze the emulsification process of the modified waterborne polyurethane waterproofing agent, and the waterborne polyurethane waterproofing agent with unqualified emulsification process leads to poor stability, thereby leading to the problem of poor weather resistance of the waterborne polyurethane waterproofing agent. Summary of the invention

[0004] To this end, the present invention provides a method for preparing a weather-resistant waterborne polyurethane waterproofing agent, so as to overcome the problem of poor weather resistance of the waterborne polyurethane waterproofing agent in the prior art.

[0005] To achieve the above object, the present invention provides a method for preparing a weather-resistant waterborne polyurethane waterproofing agent, comprising:

[0006] Step S1, mixing a plurality of materials with a polyester amine prepolymer solution, heating the mixture to a preset polymerization reaction temperature at a preset pH value, and maintaining the mixture for a preset polymerization time to perform a polymerization reaction to obtain an aqueous polyurethane solution, wherein the materials include a curing agent, an auxiliary agent, a catalyst, a hydrophilic agent, and polyethylene oxide;

[0007] Step S2, determining the eligibility of the dispersion state of the aqueous polyurethane solution according to the agglomeration evaluation value of the aqueous polyurethane solution;

[0008] Step S3, under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, determining to adjust the shear force of the high-speed emulsifier in the emulsification process of the aqueous polyurethane solution based on the ratio of the agglomeration evaluation value to a preset agglomeration evaluation value;

[0009] Step S4, mixing several raw materials in a reactor to obtain a mixed solution, heating the mixed solution to a preset condensation reaction temperature and maintaining the mixed solution for a preset condensation time to perform a condensation reaction to obtain a modified nano-imogolite solution, wherein the raw materials include a nano-imogolite solution and a silane coupling agent;

[0010] Step S5, blending the modified nano-imogolite solution with the aqueous polyurethane solution in a qualified dispersion state to obtain a reaction solution, heating the reaction solution to a preset cross-linking reaction temperature at a preset pH value and maintaining the cross-linking reaction time for a preset cross-linking reaction to obtain an aqueous polyurethane waterproofing agent;

[0011] Step S6, subjecting the waterborne polyurethane waterproofing agent to vacuum degassing to obtain a weather-resistant waterborne polyurethane waterproofing agent, and determining the eligibility of the weather-resistant waterborne polyurethane waterproofing agent based on the bubble evaluation value of the waterborne polyurethane waterproofing agent subjected to vacuum degassing;

[0012] Step S7, under the condition that the weather-resistant water-based polyurethane waterproofing agent is determined to be unqualified, determining and adjusting the vacuum pressure of the vacuum degassing treatment based on the difference between a preset bubble evaluation value and the bubble evaluation value.

[0013] Furthermore, in the step S1, a plurality of materials are mixed with the polyesteramine prepolymer solution and then heated to a preset polymerization reaction temperature at a preset pH value and maintained for a preset polymerization time to complete the polymerization reaction, wherein the preset pH value range is 6.0-7.4, the preset polymerization reaction temperature range is 60°C-80°C, and the preset polymerization time is 12h.

[0014] Further, in step S2, under the condition of determining the preparation of the aqueous polyurethane solution, it is determined that the dispersion state of the aqueous polyurethane solution is unqualified based on the comparison result that the agglomeration evaluation value of the aqueous polyurethane solution is less than or equal to a preset agglomeration evaluation value.

[0015] Further, under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, based on the comparison result that the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value is less than or equal to the preset ratio, it is determined to increase the shear force of the high-speed emulsifier by the first preset shear force adjustment coefficient.

[0016] Further, under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, based on the comparison result that the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value is greater than the preset ratio, it is determined to increase the shear force of the high-speed emulsifier by a second preset shear force adjustment coefficient.

[0017] Furthermore, in step S4, a plurality of raw materials are mixed in a reactor to obtain a mixed solution, and the mixed solution is heated to a preset condensation reaction temperature and maintained for a preset condensation time to complete the condensation reaction, wherein the preset condensation reaction temperature ranges from 70°C to 120°C, and the preset condensation time is 10 hours.

[0018] Furthermore, in step S5, the reaction solution is heated to a preset cross-linking reaction temperature at a preset pH value and maintained for a preset cross-linking reaction time to complete the cross-linking reaction, wherein the preset pH value range is 7-8, the preset cross-linking reaction temperature range is 60°C-70°C, and the preset cross-linking reaction time is 4h.

[0019] Further, in the step S6, under the condition of determining the preparation of the water-based polyurethane waterproofing agent, the water-based polyurethane waterproofing agent is subjected to vacuum degassing treatment to obtain a weather-resistant water-based polyurethane waterproofing agent, and based on the comparison result that the bubble evaluation value of the water-based polyurethane waterproofing agent subjected to vacuum degassing treatment is less than or equal to a preset bubble evaluation value, it is determined that the weather resistance of the weather-resistant water-based polyurethane waterproofing agent is unqualified.

[0020] Further, under the condition that the weather resistance of the weather-resistant waterborne polyurethane waterproofing agent is determined to be unqualified, a first preset pressure adjustment coefficient is determined to increase the vacuum pressure of the vacuum degassing treatment based on the difference between a preset bubble evaluation value and the bubble evaluation value being less than or equal to a preset difference.

[0021] Further, under the condition that the weather resistance of the weather-resistant water-based polyurethane waterproofing agent is determined to be unqualified, based on the difference between a preset bubble evaluation value and the bubble evaluation value being greater than a preset difference, a second preset pressure adjustment coefficient is determined to increase the vacuum pressure of the vacuum degassing treatment.

[0022] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention prepares an aqueous polyurethane solution and evaluates the dispersion state, adjusts the emulsification shear force for the aqueous polyurethane solution with an unqualified dispersion state, prepares a modified nano-imogeosite solution, and blends it with the aqueous polyurethane solution with a qualified dispersion state to carry out a cross-linking reaction to obtain an aqueous polyurethane waterproofing agent, obtains a weather-resistant aqueous polyurethane waterproofing agent by performing a vacuum degassing treatment and evaluates the weather resistance of the waterproofing agent, adjusts the vacuum pressure of the vacuum degassing treatment for the unqualified weather resistance, accurately controls the polymerization reaction and the dispersion state of the aqueous polyurethane, combines the enhanced cross-linking effect of the modified nano-imogeosite, and adjusts the fine parameters of the vacuum degassing treatment, effectively enhances the structural stability and environmental adaptability of the waterproofing agent, ensures the long-term durability under adverse climatic conditions, and thus improves the weather resistance of the aqueous polyurethane waterproofing agent.

[0023] Furthermore, the present invention strictly controls the polymerization conditions and evaluates the dispersion state of the aqueous polyurethane solution through the agglomeration evaluation value. For the aqueous polyurethane solution with unqualified dispersion state, the shear force of the emulsification process is adjusted according to the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value, thereby ensuring the uniform dispersion of the aqueous polyurethane solution. Through the targeted shear force adjustment, the structural stability of the aqueous polyurethane solution is effectively enhanced and the service life is extended.

[0024] Furthermore, the present invention mixes a nano-imogeosilicon solution and a silane coupling agent, completes a condensation reaction at a certain temperature, and then heats the reaction solution to a certain temperature within a certain pH range to complete a cross-linking reaction to obtain a water-based polyurethane waterproofing agent, thereby strengthening the binding force between the nano-imogeosilicon and the water-based polyurethane, significantly improving the structural stability and weather resistance of the waterproofing agent, effectively enhancing the adaptability of the water-based polyurethane waterproofing agent, and maintaining stable performance for a long time under adverse climatic conditions, thereby enhancing the weather resistance of the water-based polyurethane waterproofing agent.

[0025] Furthermore, the present invention removes bubbles through vacuum degassing treatment, and evaluates the weather resistance of the water-based polyurethane waterproofing agent based on the comparison result of the bubble evaluation value and the preset bubble evaluation value. If the weather resistance is unqualified, the vacuum pressure of the vacuum degassing treatment is adjusted according to the difference between the bubble evaluation value and the preset bubble evaluation value, thereby ensuring the high quality of the waterproofing agent after the vacuum degassing treatment. By precisely controlling the vacuum pressure, the number of bubbles is effectively reduced, thereby significantly improving the weather resistance of the waterproofing agent, making the waterproofing agent more adaptable to complex and changeable climate environments, extending the service life, and enhancing the weather resistance of the water-based polyurethane waterproofing agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a flow chart of a method for preparing a weather-resistant waterborne polyurethane waterproofing agent according to an embodiment of the present invention;

[0027] Figure 2 A flow chart for determining the eligibility of the dispersion state of an aqueous polyurethane solution according to an embodiment of the present invention;

[0028] Figure 3 A flow chart for determining the weather resistance qualification of a weather-resistant waterborne polyurethane waterproofing agent according to an embodiment of the present invention;

[0029] Figure 4 A flow chart for determining and adjusting the vacuum pressure for a vacuum degassing process according to an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0032] It should be pointed out that the data in this embodiment are obtained by comprehensive analysis and evaluation of the historical test data and the corresponding historical test results of the present invention in the three months before this test. It can be understood by those skilled in the art that the present invention can determine the above parameters for a single item by selecting the highest proportion of values ​​as the preset standard parameters according to the data distribution, using weighted summation to use the obtained values ​​as the preset standard parameters, substituting each historical data into a specific formula and using the values ​​obtained by the formula as the preset standard parameters or other selection methods, as long as the present invention can clearly define different specific situations in the single determination process through the obtained values.

[0033] See also Figure 1-Figure 4 As shown, Figure 1 This is a flow chart of a method for preparing a weather-resistant waterborne polyurethane waterproofing agent according to an embodiment of the present invention; Figure 2 A flow chart for determining the eligibility of the dispersion state of an aqueous polyurethane solution according to an embodiment of the present invention; Figure 3 A flow chart for determining the weather resistance qualification of a weather-resistant waterborne polyurethane waterproofing agent according to an embodiment of the present invention; Figure 4 A flow chart for determining and adjusting the vacuum pressure for a vacuum degassing process according to an embodiment of the present invention.

[0034] The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to the embodiment of the present invention comprises:

[0035] Step S1, mixing a plurality of materials with a polyester amine prepolymer solution, heating the mixture to a preset polymerization reaction temperature at a preset pH value, and maintaining the mixture for a preset polymerization time to perform a polymerization reaction to obtain an aqueous polyurethane solution, wherein the materials include a curing agent, an auxiliary agent, a catalyst, a hydrophilic agent, and polyethylene oxide;

[0036] Step S2, determining the eligibility of the dispersion state of the aqueous polyurethane solution according to the agglomeration evaluation value of the aqueous polyurethane solution;

[0037] Step S3, under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, determining to adjust the shear force of the high-speed emulsifier in the emulsification process of the aqueous polyurethane solution based on the ratio of the agglomeration evaluation value to a preset agglomeration evaluation value;

[0038] Step S4, mixing several raw materials in a reactor to obtain a mixed solution, heating the mixed solution to a preset condensation reaction temperature and maintaining the mixed solution for a preset condensation time to perform a condensation reaction to obtain a modified nano-imogolite solution, wherein the raw materials include a nano-imogolite solution and a silane coupling agent;

[0039] Step S5, blending the modified nano-imogolite solution with the aqueous polyurethane solution in a qualified dispersion state to obtain a reaction solution, heating the reaction solution to a preset cross-linking reaction temperature at a preset pH value and maintaining the cross-linking reaction time for a preset cross-linking reaction to obtain an aqueous polyurethane waterproofing agent;

[0040] Step S6, subjecting the waterborne polyurethane waterproofing agent to vacuum degassing to obtain a weather-resistant waterborne polyurethane waterproofing agent, and determining the eligibility of the weather-resistant waterborne polyurethane waterproofing agent based on the bubble evaluation value of the waterborne polyurethane waterproofing agent subjected to vacuum degassing;

[0041] Step S7, under the condition that the weather-resistant water-based polyurethane waterproofing agent is determined to be unqualified, determining and adjusting the vacuum pressure of the vacuum degassing treatment based on the difference between a preset bubble evaluation value and the bubble evaluation value.

[0042] In the embodiment of the present invention, the curing agent is hexamethylene diisocyanate, accounting for (5%) in the total amount, the auxiliary agent includes a pigment, a filler, a defoamer, a dispersant, an antioxidant and a light stabilizer, the pigment is titanium dioxide, the amount of which is 20% of the auxiliary agent, the filler is calcium carbonate, the amount of which is 40% of the auxiliary agent, the defoamer is an organosilicon defoamer, the amount of which is 5% of the auxiliary agent, the dispersant is an ammonium polyacrylate dispersant, the amount of which is 15% of the auxiliary agent, the antioxidant is 2,6-di-tert-butyl-4-methylphenol, the amount of which is 10% of the auxiliary agent, and the light stabilizer is a hindered amine light stabilizer, the amount of which is The amount is 10% of the auxiliary agent, the auxiliary agent accounts for 20% of the total amount, the polyethylene oxide accounts for 10% of the total amount, the hydrophilic agent is dimethylolpropionic acid, accounting for 2% of the total amount, the catalyst is dibutyltin dilaurate, accounting for 0.1%-0.5% of the total amount, the polyester amine prepolymer solution is 40%-45%, the nano-imago stone solution is 17%-22%, and the silane coupling agent is γ-glycidyloxypropyltrimethoxysilane, accounting for 0.5%-1% of the total amount, wherein the total amount is the total amount of the prepared weather-resistant water-based polyurethane waterproofing agent.

[0043] In the embodiment of the present invention, the agglomeration evaluation value is determined by measuring the particle size of particles in the aqueous polyurethane solution using a particle size analyzer, and the bubble evaluation value is determined by measuring the diameter of bubbles in the aqueous polyurethane waterproofing agent using an image acquisition device.

[0044] In the embodiment of the present invention, the particle size analyzer is an instrument used for particle size analysis, including but not limited to a laser particle size analyzer and / or a dynamic light scattering instrument.

[0045] In the embodiment of the present invention, the image acquisition device includes but is not limited to a camera, an industrial camera and / or an infrared camera.

[0046] In the embodiment of the present invention, the high-speed emulsifier is a high-pressure emulsifier and / or a roller emulsifier.

[0047] Specifically, the present invention prepares an aqueous polyurethane solution and evaluates the dispersion state, adjusts the emulsification shear force for the aqueous polyurethane solution with an unqualified dispersion state, prepares a modified nano-imogeosite solution, and blends it with the aqueous polyurethane solution with a qualified dispersion state to carry out a cross-linking reaction to obtain an aqueous polyurethane waterproofing agent, obtains a weather-resistant aqueous polyurethane waterproofing agent by performing a vacuum degassing treatment and evaluates the weather resistance of the waterproofing agent, adjusts the vacuum pressure of the vacuum degassing treatment for the aqueous polyurethane with unqualified weather resistance, accurately controls the polymerization reaction and the dispersion state of the aqueous polyurethane, combines the enhanced cross-linking effect of the modified nano-imogeosite, and adjusts the fine parameters of the vacuum degassing treatment, effectively enhances the structural stability and environmental adaptability of the waterproofing agent, ensures the long-term durability under adverse climatic conditions, and thus improves the weather resistance of the aqueous polyurethane waterproofing agent.

[0048] Specifically, in step S1, a plurality of materials are mixed with a polyester amine prepolymer solution, and then the mixture is heated to a preset polymerization reaction temperature at a preset pH value and maintained for a preset polymerization time to complete the polymerization reaction, wherein the preset pH value range is 6.0-7.4, the preset polymerization reaction temperature range is 60°C-80°C, and the preset polymerization time is 12h.

[0049] Specifically, in the embodiment of the present invention, under the conditions for obtaining the aqueous polyurethane solution, the eligibility of the dispersion state of the aqueous polyurethane solution is determined according to the comparison result of the agglomeration evaluation value of the aqueous polyurethane solution and the preset agglomeration evaluation value of 0.95;

[0050] When the agglomeration evaluation value is less than or equal to the preset agglomeration evaluation value, it is determined that the dispersion state of the aqueous polyurethane solution is unqualified;

[0051] When the agglomeration evaluation value is greater than the preset agglomeration evaluation value, it is determined that the dispersion state of the aqueous polyurethane solution is qualified.

[0052] In the embodiment of the present invention, the preset agglomeration evaluation value is 0.95. The preset agglomeration evaluation value is obtained by taking the average value of several historical agglomeration evaluation values ​​of the aqueous polyurethane solution with qualified dispersion state, but the above value is not limited to this. Those skilled in the art can also adjust the value according to actual needs.

[0053] Specifically, the agglomeration evaluation value is the ratio of the difference between the actual average particle size and the expected average particle size of the particles in the aqueous polyurethane solution to the expected average particle size.

[0054] Specifically, in the embodiment of the present invention, under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, the shear force of the high-speed emulsifier in the emulsification process of the aqueous polyurethane solution is adjusted according to the comparison result of the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value and the preset ratio 0.91;

[0055] When the ratio is less than or equal to the preset ratio, it is determined that the shear force of the high-speed emulsifier in the emulsification process of the aqueous polyurethane solution is increased to a corresponding value by using a first preset shear force adjustment coefficient of 1.05;

[0056] When the ratio is greater than the preset ratio, it is determined that the shear force of the high-speed emulsifier in the emulsification process of the aqueous polyurethane solution is increased to a corresponding value by using a second preset shear force adjustment coefficient of 1.09;

[0057] The ratio is the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value.

[0058] In the embodiment of the present invention, the preset ratio is 0.91, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0059] In the embodiment of the present invention, the increased shear force is the product of the shear force and the i-th preset shear force adjustment coefficient, where i is 1 or 2, T1 represents the first preset shear force adjustment coefficient of 1.05, and T2 represents the second preset shear force adjustment coefficient of 1.09.

[0060] Specifically, the present invention strictly controls the polymerization conditions and evaluates the dispersion state of the aqueous polyurethane solution through the agglomeration evaluation value. For the aqueous polyurethane solution with unqualified dispersion state, the shear force of the emulsification process is adjusted according to the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value, thereby ensuring the uniform dispersion of the aqueous polyurethane solution. Through the targeted shear force adjustment, the structural stability of the aqueous polyurethane solution is effectively enhanced and the service life is extended.

[0061] Specifically, in step S4, several raw materials are mixed in a reactor to obtain a mixed solution, and the mixed solution is heated to a preset condensation reaction temperature and maintained for a preset condensation time to complete the condensation reaction, wherein the preset condensation reaction temperature ranges from 70°C to 120°C, and the preset condensation time is 10 hours.

[0062] Specifically, in step S5, the reaction solution is heated to a preset cross-linking reaction temperature at a preset pH value and maintained for a preset cross-linking reaction time to complete the cross-linking reaction, wherein the preset pH value range is 7-8, the preset cross-linking reaction temperature range is 60°C-70°C, and the preset cross-linking reaction time is 4h.

[0063] Specifically, the present invention mixes a nano-imogeosilicon solution and a silane coupling agent, completes a condensation reaction at a certain temperature, and then heats the reaction solution to a certain temperature within a certain pH range to complete a cross-linking reaction to obtain a water-based polyurethane waterproofing agent, thereby strengthening the bonding force between the nano-imogeosilicon and the water-based polyurethane, significantly improving the structural stability and weather resistance of the waterproofing agent, effectively enhancing the adaptability of the water-based polyurethane waterproofing agent, and maintaining stable performance for a long time under adverse climatic conditions, thereby enhancing the weather resistance of the water-based polyurethane waterproofing agent.

[0064] Specifically, in the embodiment of the present invention, under the conditions for obtaining the water-based polyurethane waterproofing agent, the water-based polyurethane waterproofing agent is subjected to vacuum degassing to obtain a weather-resistant water-based polyurethane waterproofing agent, and the eligibility of the weather-resistant water-based polyurethane waterproofing agent is determined based on the comparison result of the bubble evaluation value of the water-based polyurethane waterproofing agent subjected to vacuum degassing and the preset bubble evaluation value of 0.88;

[0065] When the bubble evaluation value is less than or equal to the preset bubble evaluation value, it is determined that the weather resistance of the weather-resistant waterborne polyurethane waterproofing agent is unqualified;

[0066] When the bubble evaluation value is greater than the preset bubble evaluation value, it is determined that the weather resistance of the weather-resistant waterborne polyurethane waterproofing agent is qualified.

[0067] In the embodiment of the present invention, the preset bubble evaluation value is 0.88, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0068] Specifically, the bubble evaluation value is the ratio of the difference between the maximum diameter of the bubbles and the minimum diameter of the bubbles during the vacuum degassing process to the average diameter of the bubbles.

[0069] Specifically, in the embodiment of the present invention, under the condition that the weather resistance of the weather-resistant waterborne polyurethane waterproofing agent is determined to be unqualified, the vacuum pressure of the vacuum degassing treatment is determined to be adjusted according to the comparison result of the difference between the preset bubble evaluation value and the bubble evaluation value and the preset difference value of 0.26;

[0070] When the difference is less than or equal to the preset difference, it is determined that the vacuum pressure of the vacuum degassing process is increased to a corresponding value by a first preset pressure adjustment coefficient of 1.09;

[0071] When the difference is greater than the preset difference, it is determined that the vacuum pressure of the vacuum degassing process is increased to a corresponding value by a second preset pressure adjustment coefficient of 1.12;

[0072] The difference is the difference between a preset bubble evaluation value and the bubble evaluation value.

[0073] In the embodiment of the present invention, the preset difference value is 0.26, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0074] In the embodiment of the present invention, the increased vacuum pressure is the product of the vacuum pressure of the vacuum degassing treatment and the jth preset pressure adjustment coefficient, L1 represents the first preset pressure adjustment coefficient of 1.09, and L2 represents the second preset pressure adjustment coefficient of 1.12.

[0075] Specifically, the present invention removes bubbles through vacuum degassing treatment, and evaluates the weather resistance of the water-based polyurethane waterproofing agent based on the comparison result of the bubble evaluation value and the preset bubble evaluation value. If the weather resistance is unqualified, the vacuum pressure of the vacuum degassing treatment is adjusted according to the difference between the bubble evaluation value and the preset bubble evaluation value, thereby ensuring the high quality of the waterproofing agent after the vacuum degassing treatment. By precisely controlling the vacuum pressure, the number of bubbles is effectively reduced, thereby significantly improving the weather resistance of the waterproofing agent, making the waterproofing agent more adaptable to complex and changeable climate environments, extending the service life, and enhancing the weather resistance of the water-based polyurethane waterproofing agent.

[0076] Embodiment 1:

[0077] (1) 50 g of hexamethylene diisocyanate, 40 g of titanium dioxide, 80 g of calcium carbonate, 10 g of silicone defoamer, 30 g of ammonium polyacrylate dispersant, 20 g of 2,6-di-tert-butyl-4-methylphenol, 20 g of hindered amine light stabilizer, 5 g of dibutyltin dilaurate, 20 g of dimethylolpropionic acid, 100 g of polyethylene oxide, and 450 g of polyester amine prepolymer solution were heated at a pH value of 6.5 and a reaction temperature of 70° C. for 12 hours to obtain an aqueous polyurethane solution;

[0078] (2) 170 g of nano-imogolite solution and 5 g of γ-glycidyloxypropyltrimethoxysilane were heated at 90° C. for 10 h to obtain a modified nano-imogolite solution;

[0079] (3) heating the modified nano-imogeosite solution and the aqueous polyurethane solution at a pH value of 7.5 and a reaction temperature of 65° C. for 4 h to obtain an aqueous polyurethane waterproofing agent;

[0080] (4) The water-based polyurethane waterproofing agent is subjected to vacuum degassing treatment to obtain a weather-resistant water-based polyurethane waterproofing agent.

[0081] Table 1 is a table of characteristic parameters of the prepared weather-resistant waterborne polyurethane waterproofing agent.

[0082]

[0083]

[0084] The standard parameters are the characteristic parameters of ordinary water-based polyurethane waterproofing agents, and the control parameters are the characteristic parameters of water-based polyurethane waterproofing agents made from modified nanocellulose whiskers.

[0085] The weather resistance test of the weather-resistant water-based polyurethane waterproofing agent was carried out. The weather-resistant water-based polyurethane waterproofing agent was placed under a radiation intensity of 0.55W / m 2 , xenon lamp aging test with a temperature of 60°C, a humidity of 50%, and an experimental duration of 1000h, the equipment is QUV, UVA-340 lamp, and the experimental duration is 500h; ultraviolet aging test, temperature is 150°C and humidity is 85%, and the experimental duration is 1000h; high temperature and high humidity aging test, salt solution concentration is 50g / L, spray pressure is 100kPa, temperature is 35°C, and the experimental duration is 48h; salt spray corrosion test, tensile strength, elongation at break and color change after the experiment are obtained (Table 2).

[0086]

[0087] Table 3 shows the tensile strength, elongation at break and color change of common waterborne polyurethane waterproofing agents in corresponding experiments under corresponding experimental conditions.

[0088]

[0089] Table 4 shows the tensile strength, elongation at break and color change of the waterborne polyurethane waterproofing agent made from modified nanocellulose whiskers under corresponding experimental conditions.

[0090]

[0091]

[0092] Specifically, according to the comparison results of tensile strength, elongation at break and color change after the weather resistance test in Table 2, Table 3 and Table 4, it is determined that the weather resistance of the weather-resistant waterborne polyurethane waterproofing agent prepared by the preparation method of the present invention is significantly enhanced.

[0093] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a weather-resistant waterborne polyurethane waterproofing agent, characterized in that: include: Step S1, mixing a plurality of materials with a polyester amine prepolymer solution, heating the mixture to a preset polymerization reaction temperature at a preset pH value, and maintaining the mixture for a preset polymerization time to perform a polymerization reaction to obtain an aqueous polyurethane solution, wherein the materials include a curing agent, an auxiliary agent, a catalyst, a hydrophilic agent, and polyethylene oxide; Step S2, determining the eligibility of the dispersion state of the aqueous polyurethane solution according to the agglomeration evaluation value of the aqueous polyurethane solution; Step S3, under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, determining to adjust the shear force of the high-speed emulsifier in the emulsification process of the aqueous polyurethane solution based on the ratio of the agglomeration evaluation value to a preset agglomeration evaluation value; Step S4, mixing several raw materials in a reactor to obtain a mixed solution, heating the mixed solution to a preset condensation reaction temperature and maintaining the mixed solution for a preset condensation time to perform a condensation reaction to obtain a modified nano-imogolite solution, wherein the raw materials include a nano-imogolite solution and a silane coupling agent; Step S5, blending the modified nano-imogolite solution with the aqueous polyurethane solution in a qualified dispersion state to obtain a reaction solution, heating the reaction solution to a preset cross-linking reaction temperature at a preset pH value and maintaining the cross-linking reaction time for a preset cross-linking reaction to obtain an aqueous polyurethane waterproofing agent; Step S6, subjecting the waterborne polyurethane waterproofing agent to vacuum degassing to obtain a weather-resistant waterborne polyurethane waterproofing agent, and determining the eligibility of the weather-resistant waterborne polyurethane waterproofing agent based on the bubble evaluation value of the waterborne polyurethane waterproofing agent subjected to vacuum degassing; Step S7, under the condition that the weather-resistant water-based polyurethane waterproofing agent is determined to be unqualified, determining and adjusting the vacuum pressure of the vacuum degassing treatment based on the difference between a preset bubble evaluation value and the bubble evaluation value.

2. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 1, characterized in that: In the step S1, a plurality of materials are mixed with a polyester amine prepolymer solution, and then the temperature is raised to a preset polymerization reaction temperature at a preset pH value and maintained for a preset polymerization time to complete the polymerization reaction, wherein the preset pH value range is 6.0-7.4, the preset polymerization reaction temperature range is 60°C-80°C, and the preset polymerization time is 12h.

3. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 2, characterized in that: In the step S2, under the condition that the aqueous polyurethane solution is prepared, it is determined that the dispersion state of the aqueous polyurethane solution is unqualified based on the comparison result that the agglomeration evaluation value of the aqueous polyurethane solution is less than or equal to a preset agglomeration evaluation value.

4. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 3, characterized in that: Under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, based on the comparison result that the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value is less than or equal to the preset ratio, it is determined to increase the shear force of the high-speed emulsifier by a first preset shear force adjustment coefficient.

5. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 3, characterized in that: Under the condition that the dispersion state of the aqueous polyurethane solution is determined to be unqualified, based on the comparison result that the ratio of the agglomeration evaluation value to the preset agglomeration evaluation value is greater than the preset ratio, it is determined to increase the shear force of the high-speed emulsifier by a second preset shear force adjustment coefficient.

6. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 1, characterized in that: In step S4, a plurality of raw materials are mixed in a reactor to obtain a mixed solution, and the mixed solution is heated to a preset condensation reaction temperature and maintained for a preset condensation time to complete the condensation reaction, wherein the preset condensation reaction temperature ranges from 70°C to 120°C, and the preset condensation time is 10 hours.

7. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 1, characterized in that: In the step S5, the reaction solution is heated to a preset cross-linking reaction temperature at a preset pH value and maintained for a preset cross-linking reaction time to complete the cross-linking reaction, wherein the preset pH value range is 7-8, the preset cross-linking reaction temperature range is 60°C-70°C, and the preset cross-linking reaction time is 4h.

8. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 7, characterized in that: In the step S6, under the conditions for obtaining the water-based polyurethane waterproofing agent, the water-based polyurethane waterproofing agent is subjected to vacuum degassing treatment to obtain a weather-resistant water-based polyurethane waterproofing agent, and based on the comparison result that the bubble evaluation value of the water-based polyurethane waterproofing agent subjected to vacuum degassing treatment is less than or equal to a preset bubble evaluation value, it is determined that the weather resistance of the weather-resistant water-based polyurethane waterproofing agent is unqualified.

9. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 8, characterized in that: Under the condition that the weather resistance of the weather-resistant waterborne polyurethane waterproofing agent is determined to be unqualified, a first preset pressure adjustment coefficient is determined to increase the vacuum pressure of the vacuum degassing treatment based on the difference between a preset bubble evaluation value and the bubble evaluation value being less than or equal to the preset difference.

10. The method for preparing the weather-resistant waterborne polyurethane waterproofing agent according to claim 8, characterized in that: Under the condition that the weather resistance of the weather-resistant water-based polyurethane waterproofing agent is determined to be unqualified, based on the difference between a preset bubble evaluation value and the bubble evaluation value being greater than the preset difference, a second preset pressure adjustment coefficient is determined to increase the vacuum pressure of the vacuum degassing treatment.

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