Low-VOC (volatile organic compound) high-performance single-component polyurethane waterproof coating and preparation method thereof

Abstract

The invention discloses a low-VOC (volatile organic compound) high-performance single-component polyurethane waterproof coating and a preparation method thereof, and belongs to the technical field of coatings. The low-VOC high-performance single-component polyurethane waterproof coating is prepared from polyether glycol, polyether triol, a dispersing agent, toner, fluorosiloxane modified needle-shaped wollastonite, non-modified powder, isocyanate, a catalyst, a latent curing agent, a defoaming agent, a high-boiling-point solvent and a polymerization inhibitor. The prepared single-component polyurethane waterproof coating has the characteristics of low VOC (volatile organic compound), low odor and no solvent, and the content of a plasticizer is far lower than that of similar products; the waterproof paint has the advantages of excellent mechanical properties, good constructability, good water resistance, good corrosion resistance, good aging resistance, hydrophobic surface, difficult adhesion of water to the surface, and good waterproof performance.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings, and specifically relates to a low-VOC high-performance single-component polyurethane waterproof coating and a preparation method thereof. Background Art

[0002] One-component polyurethane waterproof coatings are increasingly used in the construction field. First, they have outstanding performance and better flexibility and elasticity than most current water-based coatings. Second, they can adapt to complex application scenarios, such as roofs, balconies, bathrooms and other structures, and can meet various engineering construction needs. Compared with two-component polyurethane waterproof coatings, one-component polyurethane does not require stirring and mixing, and construction is more convenient. In the future roof repair market, one-component polyurethane will become one of the mainstream basic product solutions. In the current waterproof coating market, polyurethane products account for a large proportion and have broad development prospects.

[0003] The mainstream products in the market are single-component polyurethane waterproof products that meet the GB / T 19250-2013 national standard type II, with a tensile strength of 2-3MPa and a VOC of 100-200g / L. They are low-cost and occupy a large share of the market. However, their main problems are low performance, strong construction odor, and easy dust on the surface.

[0004] With the development of science and technology and the progress of the times, the construction industry has increased its performance requirements for waterproof products and has attached more and more importance to the environmental protection of waterproof products. At present, there are relatively few types of high-performance waterproof products on the market. Their environmental protection is mainly achieved by replacing traditional low-boiling point solvents with high-boiling point plasticizers. In order to control the viscosity of the system, the addition amount of high-boiling point plasticizers is usually more than 10%. For example, the addition amount of high-boiling point plasticizers in patent publications CN114437621A and CN104194609A is 15% to 30%. By adding low-viscosity high-boiling point plasticizers, the system VOC can be reduced, but the large amount of plasticizers added will affect the durability of the coating performance. As the plasticizer slowly migrates out, the tensile properties of the coating will gradually weaken. The mainstream solution for high performance is to improve the system performance by introducing urea bonds, such as patent publications CN107474713A and CN106497371A, which improve the system performance by introducing urea bonds with stronger binding force. CN202310180045.0 discloses a high-performance one-component polyurethane waterproof coating and a preparation method, which improves the system performance by introducing quaternary ammonium salt-modified layered silicate. It requires the silicate to be peeled into a flaky structure, and the process is relatively complicated. At the same time, the residual quaternary ammonium salt has a certain catalytic effect on isocyanate, which has a negative impact on storage stability.

[0005] In summary, the market needs a high-performance, low-VOC, one-component polyurethane waterproof coating to adapt to the high-end market. Summary of the invention

[0006] The present invention provides a low-VOC high-performance one-component polyurethane waterproof coating and a preparation method thereof. The one-component polyurethane waterproof coating prepared by the present invention has the characteristics of low VOC, low odor and being solvent-free, and the content of plasticizer is much lower than that of similar products; the coating has excellent mechanical properties, good construction performance, water resistance, corrosion resistance and aging resistance, and has a hydrophobic surface, so that water is not easy to adhere to the surface and has good waterproof performance.

[0007] To solve the above problems, the present invention is implemented through the following technical solutions:

[0008] The first invention object of the present invention is:

[0009] Provided is a low VOC high performance one-component polyurethane waterproof coating, which comprises the following components in weight percentage:

[0010] Polyether diol 20-40%, polyether triol 1-4%, dispersant 0.1-0.5%, color powder 0.1-0.3%, fluorosilicone modified needle-shaped wollastonite 20%-40%, non-modified powder 10-60%, isocyanate 4-9%, catalyst 0.05-0.2%, latent curing agent 0.2-0.9%, defoamer 0.1-0.5%, high boiling point solvent 5-8%, inhibitor 0.01-0.1%; the sum of all components is 100%;

[0011] The fluorosilicone-modified needle-shaped wollastonite is prepared by the following preparation method:

[0012] The fluorosilicone modifier is added into a mixed solution of ethanol and water, triethylamine is added to adjust the pH to 9-10, needle-shaped wollastonite is added while stirring, and the mixture is reacted at 40-70° C. for 3 hours, and the obtained product is filtered, washed, and dried to obtain the fluorosilicone-modified needle-shaped wollastonite;

[0013] The mass ratio of ethanol to water in the mixed solution of ethanol and water is 1.2:1;

[0014] The mass ratio of the fluorosilicone modifier to the needle-shaped wollastonite is 1:30-300.

[0015] The low VOC high performance one-component polyurethane waterproof coating of the present invention is further optimized as follows:

[0016] The molecular weight of the polyether diol is between 1000 and 2000, and the molecular weight of the polyether triol is between 3000 and 4000, wherein the mass ratio of the polyether diol to the polyether triol is 9-20.

[0017] The low VOC high performance one-component polyurethane waterproof coating of the present invention is further optimized as follows:

[0018] The fluorosilicone-modified needle-shaped wollastonite has an aspect ratio greater than 10:1, and its needle-shaped structure can effectively improve the tensile strength and tear strength of the coating.

[0019] The low VOC high performance one-component polyurethane waterproof coating of the present invention is further optimized as follows:

[0020] The fluorosilicone modifier is one or a combination of 3,3,3-trifluoropropylmethyldimethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane and tridecafluorooctyltrimethoxysilane.

[0021] The low VOC high performance one-component polyurethane waterproof coating of the present invention is further optimized as follows:

[0022] It includes one or a combination of the following technical features:

[0023] The non-modified powder is one or a combination of calcined kaolin, calcite and talc;

[0024] The isocyanate is one or a combination of toluene diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate, and the ratio of the amount of NCO group to the amount of OH in the polyol resin is between 2.00 and 2.20;

[0025] The catalyst is one or a combination of an organic metal polyurethane catalyst and a tertiary amine polyurethane catalyst; preferably one or a combination of dibutyltin dilaurate and stannous octoate.

[0026] The latent curing agent is one or a combination of an imine type latent curing agent and an oxazolidine type latent curing agent;

[0027] The high boiling point solvent is one or a combination of acetyl tributyl citrate, tributyl citrate, diisononyl phthalate, diisononyl cyclohexane-1,2-dicarboxylate, and dioctyl terephthalate;

[0028] The polymerization inhibitor is one or a combination of benzoic acid, phosphoric acid, citric acid and benzoyl chloride.

[0029] The second object of the present invention is:

[0030] A method for preparing the low-VOC high-performance one-component polyurethane waterproof coating described above (including the optimization scheme) is provided, which comprises the following preparation steps:

[0031] S1. Put polyether diol, polyether triol and dispersant into the reactor and stir at low speed for 10 min;

[0032] S2. Add color powder, fluorosilicone-modified needle-shaped wollastonite, and non-modified powder, and stir at high speed for 30 minutes;

[0033] S3. Raise the temperature to 110-120°C, evacuate to a pressure below -0.09 MPa, stir at medium speed, and maintain for 3 hours;

[0034] S4. Turn off the vacuum, cool to 80-85°C, add isocyanate and part of the high boiling point solvent, stir at medium speed, and react for 3h;

[0035] S5. Add catalyst and react for 1h;

[0036] S6. Cool down to 75-78°C, add latent curing agent and react for 1h, then turn off heating;

[0037] S7. Cool down to below 60°C, add the remaining high-boiling point solvent, defoamer, and polymerization inhibitor, evacuate to below 0.09 MPa, and stir at a low speed for 20 minutes to obtain the low-VOC high-performance one-component polyurethane waterproof coating.

[0038] The low-VOC high-performance one-component polyurethane waterproof coating prepared by the present invention has excellent mechanical properties, and its tensile strength can reach more than 6MPa, the tear strength is greater than 30N / mm, and the elongation at break is greater than 500%, which meets the requirements of GB / T 19250-2013 type II index, which is mainly due to the addition of fluorosilicone-modified needle-shaped wollastonite. The unique needle-shaped structure of needle-shaped wollastonite is similar to reinforcing fillers such as fibrous talc powder and glass fiber, which can greatly improve the mechanical properties of the system. The present invention performs surface modification on the needle-shaped wollastonite, so that the surface is connected with fluorinated siloxane groups, so that the needle-shaped wollastonite can be better dispersed in organic matter, and promotes the microphase separation inside the coating; and the modified wollastonite surface has more active groups, so that it can react with the NCO-terminated resin to form crosslinking, increase the crosslinking density of the system, and greatly improve the strength of the system.

[0039] The low-VOC high-performance one-component polyurethane waterproof coating prepared by the present invention has the characteristics of low VOC, and the amount of high-boiling point plasticizer added is much lower than that of similar products, which is due to the unique resin and powder composition of the present invention. Traditional one-component polyurethane waterproof coatings mostly use 2000 molecular weight polyether diol + 5000 molecular weight polyether triol, and the mass ratio of polyether diol and polyether triol is 2-8. In the traditional scheme, the content of triol resin is relatively high, and triol resin can improve the cross-linking density of the system and increase the strength of the system; the molecular weight of triol resin is relatively large, and it can provide three cross-linking points. The higher the content of triol resin, the greater the molecular weight of prepolymer, and the higher the viscosity of the system. The one-component polyurethane waterproof coating of the present invention uses a resin with a relatively low molecular weight, and the addition of modified wollastonite increases the cross-linking density of the system, and no longer requires too much triol resin to provide cross-linking. The proportion of triol resin is extremely low, and the molecular weight of the synthesized prepolymer is small, and the viscosity is much lower than the traditional scheme. After wollastonite is modified with fluorinated siloxane, its surface wettability is improved, and it can be better dispersed in the coating system, effectively reducing the viscosity of the coating. Due to the combination of resin and powder, the present invention only needs a small amount of plasticizer to reduce the viscosity to below 10000cp, and the plasticizer content is about half of the same type of products. Relatively speaking, the plasticizer is not easy to migrate out, and the mechanical properties are more stable.

[0040] The low VOC high-performance one-component polyurethane waterproof coating prepared by the present invention has a hydrophobic surface after curing. The surface of the fluorosilicone-modified needle-shaped wollastonite has many F groups, which greatly reduce the surface energy of the coating, making the surface of the coating hydrophobic. This hydrophobicity gives the material higher water resistance, and the low surface energy also makes the coating surface less likely to be dusty.

[0041] Thick coating of single-component polyurethane waterproof coating generally requires multiple constructions. The surface of traditional single-component polyurethane coating is very easy to be stained with dust. During the second construction, dust on the surface of the coating film will remain in the system, causing paint film defects. The present invention effectively solves this problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic diagram of a fluorosilicone modifier (left figure) and needle-shaped wollastonite modified with fluorosilicone (right figure) involved in the present invention. DETAILED DESCRIPTION

[0043] In order to make the application, technical scheme and advantages of the present invention more clear, the present invention is described in detail in conjunction with specific embodiments. It should be understood that the embodiments are only used to illustrate the present invention, but not to limit the protection scope of the present invention. All simple improvements to the preparation method of the present invention under the premise of the concept of the present invention belong to the protection scope of the present invention.

[0044] Example 1

[0045] A method for preparing a low-VOC high-performance one-component polyurethane waterproof coating, comprising the following preparation steps:

[0046] (I) Preparation of fluorosilicone modified needle-shaped wollastonite:

[0047] The fluorosilicone-modified needle-shaped wollastonite is prepared by the following preparation method:

[0048] The fluorosilicone modifier is added into a mixed solution of ethanol and water, triethylamine is added to adjust the pH to 9-10, needle-shaped wollastonite is added while stirring, and the mixture is reacted at 40-70° C. for 3 hours, and the obtained product is filtered, washed, and dried to obtain the fluorosilicone-modified needle-shaped wollastonite;

[0049] The mass ratio of ethanol to water in the mixed solution of ethanol and water is 1.2:1;

[0050] The mass ratio of the fluorosilicone modifier to the needle-shaped wollastonite is 1:200;

[0051] The fluorosilicone modifier is tridecafluorooctyltrimethoxysilane FS1310 produced by Fuzhou Taipuda New Materials Co., Ltd.

[0052] The needle-shaped wollastonite described herein is needle-shaped wollastonite powder produced by Jiangxi Kete Fine Powder Co., Ltd.

[0053] (II) Preparation of low VOC high performance one-component polyurethane waterproof coating:

[0054] The low VOC high performance one-component polyurethane waterproof coating is prepared by the following preparation steps (by weight):

[0055] S1. Put polyether diol, polyether triol and dispersant into the reactor and stir at low speed for 10 min;

[0056] S2. Add color powder, fluorosilicone-modified needle-shaped wollastonite, and non-modified powder, and stir at high speed for 30 minutes;

[0057] S3. Raise the temperature to 110-120°C, evacuate to a pressure below -0.09 MPa, stir at medium speed, and maintain for 3 hours;

[0058] S4. Turn off the vacuum, cool to 80-85°C, add isocyanate and part of the high boiling point solvent, stir at medium speed, and react for 3h;

[0059] S5. Add catalyst and react for 1h;

[0060] S6. Cool down to 75-78°C, add latent curing agent and react for 1h, then turn off heating;

[0061] S7. Cool down to below 60°C, add the remaining high-boiling point solvent, defoamer, and polymerization inhibitor, evacuate to below 0.09 MPa, and stir at a low speed for 20 minutes to obtain the low-VOC high-performance one-component polyurethane waterproof coating.

[0062] The polyether diol is VORANOL 2000LM polyether polyol produced by Dow Chemical;

[0063] The polyether triol is VORANOL 3003N polyether polyol produced by Dow Chemical;

[0064] The non-modified powder is calcite;

[0065] The isocyanate is TDI-80;

[0066] The catalyst is dibutyltin dilaurate;

[0067] The high boiling point solvent is diisononyl phthalate;

[0068] The latent curing agent is SLD-910 produced by Suzhou Sailide Chemical Co., Ltd.

[0069] The polymerization inhibitor is benzoic acid.

[0070] Example 2

[0071] A method for preparing a low-VOC high-performance one-component polyurethane waterproof coating, comprising the following preparation steps:

[0072] (I) Preparation of fluorosilicone modified needle-shaped wollastonite:

[0073] The fluorosilicone-modified needle-shaped wollastonite is prepared by the following preparation method:

[0074] The fluorosilicone modifier is added into a mixed solution of ethanol and water, triethylamine is added to adjust the pH to 9-10, needle-shaped wollastonite is added while stirring, and the mixture is reacted at 40-70° C. for 3 hours, and the obtained product is filtered, washed, and dried to obtain the fluorosilicone-modified needle-shaped wollastonite;

[0075] The mass ratio of ethanol to water in the mixed solution of ethanol and water is 1.2:1;

[0076] The mass ratio of the fluorosilicone modifier to the needle-shaped wollastonite is 1:300;

[0077] The fluorosilicone modifier is 3,3,3-trifluoropropylmethyldimethoxysilane produced by Hubei Co-Formula Material Technology Co., Ltd.

[0078] The needle-shaped wollastonite is needle-shaped wollastonite powder produced by Xinyu Juyuan Wollastonite Co., Ltd.

[0079] (II) Preparation of low VOC high performance one-component polyurethane waterproof coating:

[0080] The low VOC high performance one-component polyurethane waterproof coating is prepared by the following preparation steps (by weight):

[0081] S1. Put polyether diol, polyether triol and dispersant into the reactor and stir at low speed for 10 min;

[0082] S2. Add color powder, fluorosilicone-modified needle-shaped wollastonite, and non-modified powder, and stir at high speed for 30 minutes;

[0083] S3. Raise the temperature to 110-120°C, evacuate to a pressure below -0.09 MPa, stir at medium speed, and maintain for 3 hours;

[0084] S4. Turn off the vacuum, cool to 80-85°C, add isocyanate and part of the high boiling point solvent, stir at medium speed, and react for 3h;

[0085] S5. Add catalyst and react for 1h;

[0086] S6. Cool down to 75-78°C, add latent curing agent and react for 1h, then turn off heating;

[0087] S7. Cool down to below 60°C, add the remaining high-boiling point solvent, defoamer, and polymerization inhibitor, evacuate to below 0.09 MPa, and stir at a low speed for 20 minutes to obtain the low-VOC high-performance one-component polyurethane waterproof coating.

[0088] The polyether diol is DL-2000D produced by Shandong Bluestar Dongda Co., Ltd.

[0089] The polyether triol described is DL-4000D produced by Shandong Bluestar Dongda Co., Ltd.

[0090] The non-modified powder is talcum powder;

[0091] The isocyanate is MDI-50;

[0092] The catalyst is dibutyltin dilaurate;

[0093] The high boiling point solvent is acetyl tributyl citrate ATBC;

[0094] The latent curing agent is ALT-401 produced by Changde Ailite New Material Technology Co., Ltd.

[0095] The polymerization inhibitor is benzoyl chloride.

[0096] Comparative Example 1

[0097] The preparation of the fluorosilicone-modified needle-shaped wollastonite in Comparative Example 1 is consistent with that in Example 1.

[0098] In the preparation steps of the one-component polyurethane waterproof coating of Comparative Example 1, the added portion of fluorosilicone-modified needle-shaped wollastonite is 46.44 parts, and the added portion of non-modified powder is 0 parts; the rest is consistent with Example 1.

[0099] Comparative Example A

[0100] Put polyether diol and polyether triol into the reaction kettle, evacuate to the pressure below -0.09MPa, stir at medium speed, and keep for 3h;

[0101] Turn off the vacuum, cool to 80-85°C, add isocyanate, react for 3h, add catalyst, react for 1h;

[0102] When the temperature is lowered to below 60°C, the vacuum is drawn to below 0.09 MPa for 20 minutes to obtain a pure polymer system product.

[0103] The polyether diol is VORANOL 2000LM polyether polyol produced by Dow Chemical, with a molecular weight of 2000;

[0104] The polyether triol is VORANOL 3003N polyether polyol produced by Dow Chemical, with a molecular weight of 3000;

[0105] The isocyanate is TDI-80;

[0106] The catalyst is dibutyltin dilaurate.

[0107] Comparative Example 2

[0108] Comparative Example 2 does not include the step (I) of preparing the fluorosilicone-modified needle-shaped wollastonite in Example 1;

[0109] The fluorosilicone-modified needle-shaped wollastonite in Example 1 was replaced with unmodified needle-shaped wollastonite;

[0110] The rest is the same as in Example 1.

[0111] Comparative Example 3

[0112] Comparative Example 3: The needle-shaped wollastonite in the preparation step (i) of the fluorosilicone-modified needle-shaped wollastonite in Example 1 is replaced with ordinary wollastonite with a low aspect ratio, and the rest is the same as Example 1;

[0113] The preparation step (ii) of the one-component polyurethane waterproof coating in Comparative Example 3 is consistent with that in Example 1.

[0114] Comparative Example 4

[0115] The ratio of polyether diol to polyether triol in Example 1 was changed from 36:3 to 32:7, and the rest remained the same as in Example 1.

[0116] Comparative Example 5

[0117] The preparation step (I) of the fluorosilicone-modified needle-shaped wollastonite in Comparative Example 5 is consistent with that in Example 1;

[0118] The preparation step (ii) of the one-component polyurethane waterproof coating in Comparative Example 5 is different from that in Example 1 as follows:

[0119] The polyether diol in Example 1 was changed to polyether polyol 220, and the polyether triol was changed to polyether polyol 330N. In order to keep the R value consistent with that in Example 1, the amount of toluene diisocyanate TDI added was changed to 6.9; the remaining steps were consistent with Example 1.

[0120] Comparative Example B

[0121] Put polyether diol and polyether triol into the reaction kettle, evacuate to the pressure below -0.09MPa, stir at medium speed, and keep for 3h;

[0122] Turn off the vacuum, cool to 80-85°C, add isocyanate, react for 3h, add catalyst, react for 1h;

[0123] When the temperature is lowered to below 60°C, the vacuum is drawn to below 0.09 MPa for 20 minutes to obtain a pure polymer system product.

[0124] The polyether diol is polyether polyol 220;

[0125] The polyether triol is polyether polyol 330N;

[0126] The isocyanate is TDI-80;

[0127] The catalyst is dibutyltin dilaurate.

[0128] Comparative Example 6

[0129] Comparative Example 6 is a GB / T 19250-2013 national standard type II one-component polyurethane waterproof coating with a high market share.

[0130] Table 1 Raw material composition of the embodiments of the present invention and comparative examples (parts by weight)

[0131]

[0132]

[0133] Performance Test:

[0134] The physical properties of the materials of the embodiments and comparative examples were tested according to GB / T 19250-2013. The viscosity was tested using a Brookfield RV viscometer, and the water contact angle was tested using a Shengding Precision SDC-100 contact angle meter. The test results are shown in Table 2.

[0135] Table 2 Test results

[0136]

[0137] It can be seen from Example 1 and Example 2 that the one-component polyurethane waterproof coating prepared by the present invention has the characteristics of low viscosity, good mechanical properties and surface hydrophobicity.

[0138] It can be seen from Example 1 and Comparative Example 1 that increasing the amount of fluorosilicone-modified needle-shaped wollastonite can improve the tensile strength of the system and improve the surface hydrophobicity. Compared with Example 1, the elongation at break and tear strength of Comparative Example 1 are significantly reduced, which may be due to the excessive crosslinking density of the system caused by too much fluorosilicone-modified needle-shaped wollastonite, thereby reducing the flexibility. The scheme of compounding modified powder and non-modified powder can obtain better comprehensive mechanical properties.

[0139] It can be seen from Example 1 and Comparative Example 2 that the modification of needle-shaped wollastonite with fluorosilicone can greatly improve the mechanical properties of the system, and the tensile strength, elongation at break and tear strength are significantly improved after modification. This is because the modified needle-shaped wollastonite can cross-link with the polymer, thereby increasing the cross-linking density of the system. At the same time, since the surface of the needle-shaped wollastonite is modified, it is more easily wetted by the polymer, and the viscosity of the system is significantly reduced.

[0140] It can be seen from Example 1 and Comparative Example 3 that, compared with ordinary wollastonite with a low aspect ratio, needle-shaped wollastonite can significantly improve the mechanical properties of the system, especially the tear strength of the system. This is due to the special needle-shaped structure of needle-shaped wollastonite, which is distributed in the coating system like glass fiber and plays a reinforcing role.

[0141] It can be seen from Example 1 and Comparative Example 4 that the content of polyether triol should not be too high after using fluorosilicone to modify the needle-shaped wollastonite. The mass ratio of polyether diol: polyether triol in traditional one-component polyurethane is 2 to 8. Triol resin can increase the cross-linking density of the system and increase the strength of the system. After adding fluorosilicone-modified needle-shaped wollastonite, the cross-linking density of the system is already very high, and more polyether triol is no longer needed to provide the cross-linking density. Due to the excessive cross-linking density of Comparative Example 4, the elongation at break is close to the national standard limit, and its tear strength is also significantly reduced.

[0142] Comparative Example A and Comparative Example B are both pure polymer components without powder. From the performance comparison, it can be seen that the use of low molecular weight polyether triol can significantly reduce the viscosity of the prepolymer product, and the mechanical properties are also significantly improved. Combining Example 1 with Comparative Example 5, it can be seen that the viscosity of Example 1 is lower than that of Comparative Example 5, and the mechanical strength is better than that of Comparative Example 5, and its test results are consistent with the test results of pure polymer.

[0143] From Example 1 and Comparative Example 6, it can be seen that the high-performance one-component polyurethane waterproof material prepared by the present invention has the characteristics of low VOC, good mechanical properties, high tear strength, high surface hydrophobicity and stronger water resistance compared with traditional materials on the market. The present invention gives the product unique and excellent comprehensive performance through the selection of resin molecular weight, the unique ratio of polyether diol to polyether triol, and the addition of fluorosilicone-modified needle-shaped wollastonite, providing a new high-performance product for the high-end waterproof market.

[0144] To sum up, the above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any equivalent changes, modifications and evolutions made by technicians familiar with the profession without departing from the scope of the technical solution of the present invention using the disclosed technical content are regarded as equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

[0145] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0146] The experimental methods without specific conditions in the present invention are usually carried out under conventional conditions or conditions recommended by the manufacturer.

[0147] Unless otherwise stated, the various optimization technical solutions in the present invention can be combined with each other.

[0148] Unless otherwise indicated, percentages and parts are by weight.

[0149] Experimental methods without specific conditions specified in the instructions and examples are usually carried out under conventional conditions or conditions recommended by the manufacturers.

[0150] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any method and material similar or equivalent to the described content can be applied to the method of the present invention.

Claims

1. A low VOC high performance one-component polyurethane waterproof coating, characterized by: It includes the following components in weight percentage: Polyether diol 20-40%, polyether triol 1-4%, dispersant 0.1-0.5%, color powder 0.1-0.3%, fluorosilicone modified needle-shaped wollastonite 20%-40%, non-modified powder 10-60%, isocyanate 4-9%, catalyst 0.05-0.2%, latent curing agent 0.2-0.9%, defoamer 0.1-0.5%, high boiling point solvent 5-8%, inhibitor 0.01-0.1%; the sum of all components is 100%; The fluorosilicone-modified needle-shaped wollastonite is prepared by the following preparation method: The fluorosilicone modifier is added into a mixed solution of ethanol and water, triethylamine is added to adjust the pH to 9-10, needle-shaped wollastonite is added while stirring, and the mixture is reacted at 40-70° C. for 3 hours, and the obtained product is filtered, washed, and dried to obtain the fluorosilicone-modified needle-shaped wollastonite; The mass ratio of ethanol to water in the mixed solution of ethanol and water is 1.2:1; The mass ratio of the fluorosilicone modifier to the needle-shaped wollastonite is 1:30-300.

2. The low VOC high performance one-component polyurethane waterproof coating according to claim 1, characterized in that: The molecular weight of the polyether diol is between 1000 and 2000, and the molecular weight of the polyether triol is between 3000 and 4000, wherein the mass ratio of the polyether diol to the polyether triol is 9-20.

3. The low VOC high performance one-component polyurethane waterproof coating according to claim 1, characterized in that: The fluorosilicone-modified needle-shaped wollastonite has an aspect ratio greater than 10:

1.

4. The low VOC high performance one-component polyurethane waterproof coating according to claim 1, characterized in that: The fluorosilicone modifier is one or a combination of 3,3,3-trifluoropropylmethyldimethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane and tridecafluorooctyltrimethoxysilane.

5. The low VOC high performance one-component polyurethane waterproof coating according to claim 1, characterized in that: It includes one or a combination of the following technical features: The non-modified powder is one or a combination of calcined kaolin, calcite and talc; The isocyanate is one or a combination of toluene diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate, and the ratio of the amount of NCO group to the amount of OH in the polyol resin is between 2.00 and 2.20; The catalyst is one or a combination of an organic metal polyurethane catalyst and a tertiary amine polyurethane catalyst; The latent curing agent is one or a combination of an imine type latent curing agent and an oxazolidine type latent curing agent; The high boiling point solvent is one or a combination of acetyl tributyl citrate, tributyl citrate, diisononyl phthalate, diisononyl cyclohexane-1,2-dicarboxylate, and dioctyl terephthalate; The polymerization inhibitor is one or a combination of benzoic acid, phosphoric acid, citric acid and benzoyl chloride.

6. A method for preparing the low VOC high performance one-component polyurethane waterproof coating according to claim 1, characterized in that: It comprises the following preparation steps: S1. Put polyether diol, polyether triol and dispersant into the reactor and stir at low speed for 10 min; S2. Add color powder, fluorosilicone-modified needle-shaped wollastonite, and non-modified powder, and stir at high speed for 30 minutes; S3. Raise the temperature to 110-120°C, evacuate to a pressure below -0.09 MPa, stir at medium speed, and maintain for 3 hours; S4. Turn off the vacuum, cool to 80-85°C, add isocyanate and part of the high boiling point solvent, stir at medium speed, and react for 3h; S5. Add catalyst and react for 1h; S6. Cool down to 75-78°C, add latent curing agent and react for 1h, then turn off heating; S7. Cool down to below 60°C, add the remaining high-boiling point solvent, defoamer, and polymerization inhibitor, evacuate to below 0.09 MPa, and stir at a low speed for 20 minutes to obtain the low-VOC high-performance one-component polyurethane waterproof coating.

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