A bio-based polyurethane waterproof coating and a preparation method thereof
By combining bio-based resin polyols and specific additives, polyurea characteristic groups are generated, which solves the problems of sagging and low construction efficiency of polyurethane waterproof coatings, achieves rapid curing and efficient construction, and improves the compatibility and environmental performance of coatings and roofing materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LISHUI UNIV
- Filing Date
- 2026-04-03
- Publication Date
- 2026-05-29
AI Technical Summary
Existing polyurethane waterproof coatings suffer from problems such as poor anti-sagging performance, low construction efficiency, poor compatibility with waterproof membranes, and the need to use organic solvents.
It uses a combination of bio-based resin polyols and specific additives to generate polyurea characteristic groups through chemical cross-linking reaction, providing anti-sagging effect, and controls viscosity through active mineral fillers and dehydrating agents to achieve rapid curing and efficient construction.
A bio-based polyurethane waterproof coating with no organic solvents, anti-sagging properties, and rapid molding has been developed, which improves construction efficiency and the compatibility of the coating with the roll material, and meets environmental protection requirements.
Abstract
Description
Technical Field
[0001] This invention belongs to the field of waterproof coating technology, specifically relating to a bio-based polyurethane waterproof coating and its preparation method. Background Technology
[0002] Currently, there are two main types of waterproof coatings on the market: (1) One type is polymer cement-based waterproof coating, which is composed of emulsion synthesized from various water-based polymers and high-quality cement mixed with various additives. Because it takes into account both the flexibility of polymer (resin) and the rigidity of cement, the two are combined into one, achieving good waterproof performance. It also has a low overall cost and is non-toxic and environmentally friendly, but the product has poor water resistance and low elasticity. (2) The other type is polyurethane waterproof coating, which has a large elongation and high resilience. It is resistant to water immersion and corrosion by various chemicals, and has been sought after by the market since its launch.
[0003] However, most polyurethane waterproof coatings on the market currently have the following two problems: First, they do not have anti-sagging properties (the phenomenon of paint running down the coating is called sagging); second, polyurethane waterproof coatings dry and set slowly, requiring multiple layers of application, which affects the construction progress.
[0004] Regarding the first technical problem mentioned above, the current domestic solution involves adding fumed silica, nano-calcium carbonate, etc., to the coating. While this method is effective, it results in a high product viscosity, requiring the addition of large amounts of organic solvents to reduce the viscosity during application. However, organic solvents pollute the environment, cause fires, and harm workers' health, contradicting existing environmental protection requirements. Therefore, designing a new polyurethane waterproof coating that avoids the use of organic solvents is clearly a landmark achievement.
[0005] Regarding the second technical issue mentioned above, there is currently no relevant solution in China. Moreover, the actual waterproofing project conditions are complex, involving both planar and vertical construction, as well as the compatibility issues of coatings and membranes (due to the wide variety of waterproofing materials, and the frequent combination or overlap of different types of materials during waterproofing construction or repair, especially the combination or overlap of waterproof membranes and waterproof coatings, since asphalt waterproof membranes and polymer waterproof membranes are non-polar materials with low surface energy, while polyurethane coatings are polar materials with high surface energy, the overlap or combination of the two can result in poor adhesion or even detachment). Therefore, how to achieve the design thickness with a single spray of waterproof coating and then immediately lay the waterproof membrane has become the ultimate goal pursued by this industry.
[0006] Therefore, it is necessary not only to design a polyurethane waterproof coating that does not contain organic solvents, but also to make it easy to mix during the preparation process, not to lose control, and to make it easy to control the curing speed and time, so as to greatly improve the construction efficiency. This is obviously of positive practical significance. Summary of the Invention
[0007] In view of this, the present invention provides a bio-based polyurethane waterproof coating that can be sprayed, cures quickly, does not drip on vertical surfaces, is compatible with waterproof membranes, and is solvent-free, in order to improve construction efficiency, enhance quality, and protect the environment.
[0008] To achieve the above-mentioned objectives, the technical solution adopted by the present invention is: a bio-based polyurethane waterproof coating, which is composed of component A and component B by mass parts; Component A consists of the following components: 50-85 parts of bio-based resin polyol; 15-35 parts isocyanate; First adjuvant: 0.9-2 parts; Component B consists of the following components: 25-45 parts of bio-based resin polyol; 5-15 parts of petroleum asphalt; Plasticizer 8-20 parts; 35-55 parts of filler; Chain extender 2-5 parts; Catalyst 0.1~0.5 parts; Second adjuvant: 0.8-2 parts; 0.1-2 parts of dehydrating agent; The first additive is diphenylmethane diisocyanate or phenyl dimethyl isocyanate; the second additive is a di-polyetheramine or a ternary polyetheramine; the waterproof coating does not contain organic solvents.
[0009] Preferably, the bio-based resin polyols in component A and component B are the same or different, and are selected from one or more of castor oil, modified castor oil hydroxyl-terminated resin, modified soybean oil hydroxyl-terminated resin, and modified palm oil hydroxyl-terminated resin.
[0010] Preferably, the filler is selected from one or more of talc powder, kaolin, mica powder, calcium carbonate and wollastonite that have been activated by chemical coating.
[0011] Preferably, the catalyst is an organotin catalyst or an organobismuth catalyst.
[0012] Preferably, the plasticizer is selected from one or more of chlorinated paraffin, trioctyl phosphate, toluene diphenyl phosphate, diphenyl isodecanyl phosphate, dimethyl methyl phosphate, diethyl ethyl phosphate, tri(2-chloropropyl) phosphate, and tri(2-chloroethyl) phosphate.
[0013] Preferably, the chain extender is selected from one or more of dimethylthiotoluene diamine, 4,4'-di(alkylamino)-diphenylmethane, N,N'-dialkylphenyldiamine, 4,4'-di(alkylamino)-dicyclohexylmethane, and polyaspartic acid esters prepared by the Michael addition reaction of dialkyl maleate and aliphatic primary diamine.
[0014] Preferably, the dehydrating agent is selected from one or more of calcium oxide, magnesium oxide, and vinylalkoxysilane coupling agents.
[0015] This invention also claims protection for a method for preparing a bio-based polyurethane waterproof coating, comprising the following steps: the two-component waterproof coating is composed of component A and component B; The manufacturing method of component A includes the following steps: adding polyether polyol to a reaction vessel, purging with nitrogen for protection, heating to above 80°C, adding isocyanate, stirring and mixing at 70~90°C for at least 1 hour, then cooling to 60°C, adding the first auxiliary agent, and continuing to stir for at least 10 minutes to obtain component A. The manufacturing method of component B includes the following steps: adding bio-based resin polyol, plasticizer and chain extender to a reaction vessel, purging with nitrogen for protection, heating to 70-90℃, then adding petroleum asphalt, and after the petroleum asphalt melts, adding filler and dispersing for at least 30 minutes. The material is then transferred to another reaction vessel via a grinding pump. After determining the moisture content, the corresponding dehydrating agent is added and stirred for 10-30 minutes. A catalyst and a second auxiliary agent are added and stirred for 10-30 minutes to obtain component B.
[0016] The working principle of this invention is as follows: Specific first and second additives are added to components A and B, respectively. The first additive in component A has higher reactivity than isocyanate, and the second additive in component B has higher reactivity than chain extender. When components A and B are mixed, the first and second additives preferentially and rapidly undergo chemical cross-linking to generate small molecule substances containing polyurea characteristic groups. This substance provides thixotropy to the polyurethane waterproof coating, producing an anti-sagging effect and ensuring the smoothness and uniformity of the coating surface and thickness. Compared with traditional high-molecular-weight polyurea structures, the advantage of the small molecule substances generated by this invention is that they produce an anti-sagging effect without increasing the viscosity of the system. Furthermore, the reaction of the first and second additives is completed instantaneously (within 20 seconds) during mixing, therefore, when mechanical spraying is used, mixing and spraying can be performed simultaneously without sagging. By selecting a specific chain extender and a combination of trace catalysts to improve the curing speed, the product can achieve surface drying within minutes and complete drying within 30 minutes. This allows for a single thick coating, and the next process can be carried out immediately after the product is completely dry, thus greatly improving construction efficiency and saving construction time.
[0017] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: 1. This invention develops a novel bio-based polyurethane waterproof coating. The product is modified using bio-based resin. Because the polyol molecules of the bio-based resin have a carbon-carbon structure as their main chain, their carbon-oxygen main chain polarity is much weaker than that of traditional polyethylene oxide polyols or polypropylene oxide polyols. This reduces the polarity of the polyurethane waterproof coating, improves the peel strength between the coating and the membrane, enhances the compatibility of the polyurethane waterproof coating with polymer membranes and bitumen-based waterproof membranes, and simultaneously reduces carbon emissions, contributing to the green development of the industry.
[0018] 2. By using surface-modified active mineral fillers, this invention can greatly improve the problems of significantly increased system viscosity and powder sedimentation caused by mineral fillers.
[0019] 3. This invention controls the moisture content of materials by adding a dehydrating agent, eliminating the need for a dehydration process, thereby saving energy and improving production efficiency.
[0020] 4. The product of this invention has the characteristics of being solvent-free, anti-sagging, and rapid-forming, and is especially suitable for spraying operations, with high construction efficiency, which has positive practical significance. Detailed Implementation
[0021] The present invention will be further described below with reference to embodiments.
[0022] Example 1 This embodiment provides a bio-based polyurethane waterproof coating, comprising component A and component B (the two are mixed in a 1:1 ratio). By weight, component A contains 80 parts of modified castor oil polyol (brand name Uric H-62, Ito Chemical, Japan), 19 parts of toluene diisocyanate (brand name T-80, Yantai Wanhua Chemical), and 2 parts of diphenylmethane diisocyanate (brand name MI-50, Yantai Wanhua Chemical). Component B raw materials include 25 parts of modified castor oil polyol (brand name Uric F-15, Ito Chemical, Japan), 15 parts of No. 90 petroleum asphalt, 3 parts of N,N'-dialkylphenyl diamine (brand name Wanalink 6200, Wanhua Chemical), 19.49 parts of chlorinated paraffin (brand name No. 52, Danyang Suxing New Materials), 40 parts of activated fine calcium carbonate (brand name carb 5T, Omia), 0.1 parts of dibutyltin dilaurate (brand name T-12, Jiangsu Mingtai New Materials), 2 parts of di-polyetheramine (brand name CAD230, Yangzhou Chenhua), and 0.5 parts of vinyltrimethoxysilane (brand name WD-21, Wuhan University Organosilicon).
[0023] Its preparation method specifically includes: Preparation of component A: Modified castor oil polyol was added to the reaction vessel, nitrogen gas was introduced for protection, the temperature was raised to 80°C, toluene diisocyanate was added, and the mixture was stirred at 70~90°C for 2 hours. Then the temperature was lowered to 60°C, diphenylmethane diisocyanate was added, and the mixture was stirred for another 25 minutes to obtain component A. Preparation of Component B: Modified castor oil polyol, chlorinated paraffin, and N,N'-dialkylphenyl diamine were added to a reactor. Nitrogen gas was introduced for protection, and the temperature was raised to 70-90℃. Petroleum asphalt was then added. After the asphalt melted, 40 parts of carb 5T calcium powder were added. The material was kept at a constant temperature of 70-90℃ and subjected to high-speed shearing for 30 minutes. The material was then transferred to another reactor via a grinding pump without heating or cooling. The moisture content was measured using a moisture analyzer. The corresponding vinyltrimethoxysilane was added and stirred for 20 minutes. The catalyst and di-polyetheramine were then added and stirred for 25 minutes to obtain Component B.
[0024] Example 2 This embodiment provides a bio-based polyurethane waterproof coating, comprising component A and component B (the two are mixed in a 1:1 ratio). By weight, component A contains 75 parts of modified castor oil polyol (brand name Uric H-57, Ito Chemical, Japan), 23 parts of toluene diisocyanate (brand name T-80, Yantai Wanhua Chemical), and 2 parts of polyphenyl polymethylene polycyanate (brand name PM-200, Yantai Wanhua Chemical).
[0025] Component B raw materials include 33 parts of modified soybean oil polyol (brand name FH-2120, Jiangsu Feihang Technology), 10 parts of petroleum asphalt, 5 parts of N,N'-dialkylphenyl diamine (brand name Wanalink 6200, Wanhua Chemical), 19 parts of diethyl phosphate (brand name DEEP, Yangzhou Chenhua), 38 parts of activated calcium carbonate (brand name carb 2T, Omia), 0.2 parts of stannous octoate (brand name T-9, Jiangsu Yake Chemical), 1.5 parts of ternary polyetheramine (brand name CAT403, Yangzhou Chenhua), and 1 part of fine magnesium oxide (brand name MS-180, Hebei Meishen Technology).
[0026] The preparation method is the same as in Example 1.
[0027] Comparative Example 1 This embodiment provides a bio-based polyurethane waterproof coating, comprising component A and component B, wherein the mixing ratio of component A and component B is 1:1; By weight, the raw materials of component A include 80 parts of modified castor oil polyol (brand name Uric H-62, Ito Chemical, Japan) and 19 parts of toluene diisocyanate (brand name T-80, Yantai Wanhua Chemical). Component B raw materials include 25 parts of modified castor oil polyol (brand name Uric F-15, Ito Chemical, Japan), 15 parts of No. 90 petroleum asphalt, 3 parts of N,N'-dialkylphenyl diamine (brand name Wanalink 6200, Wanhua Chemical), 19.49 parts of chlorinated paraffin (brand name No. 52, Danyang Suxing New Materials), 42 parts of activated fine calcium carbonate (brand name carb 5T, Omia), 0.1 parts of dibutyltin dilaurate (brand name T-12, Jiangsu Mingtai New Materials), and 0.5 parts of vinyltrimethoxysilane (brand name WD-21, Wuhan University Organosilicon).
[0028] The preparation method is the same as in Example 1.
[0029] Comparative Example 2 This embodiment provides a sprayable, fast-drying, bio-based polyurethane waterproof coating, comprising component A and component B, wherein the mixing ratio of component A and component B is 1:1; By weight, the raw materials of component A include 80 parts of polypropylene oxide polyol (brand name DL-1000D, Lanxing Dongda Chemical), 17 parts of toluene diisocyanate (brand name T-80, Yantai Wanhua Chemical), and 3 parts of diphenylmethane diisocyanate (brand name MI-50, Yantai Wanhua Chemical). Component B raw materials include 20 parts of polypropylene oxide polyol (brand name EP-3600, Lanxing Dongda Chemical), 15 parts of No. 90 petroleum asphalt, 3 parts of N,N'-dialkylphenyl diamine (brand name Wanalink 6200, Wanhua Chemical), 19 parts of chlorinated paraffin (brand name 52, Danyang Suxing New Materials), 39.5 parts of activated fine calcium carbonate (brand name carb 5T, Omia), 0.1 parts of dibutyltin dilaurate (brand name T-12, Jiangsu Mingtai New Materials), 2 parts of di-polyetheramine (brand name CAD230, Yangzhou Chenhua), 1 part of vinyltrimethoxysilane (brand name WD-21, Wuhan University Organosilicon), and 30 parts of organic solvent.
[0030] The preparation method is the same as in Example 1.
[0031] The examples and comparative examples were tested for surface drying time, complete drying time, and anti-sagging properties according to standard T / CECS10302-2023 "Anti-Sagging Polyurethane Waterproof Coating". The peel strength between the polyurethane waterproof coating and the waterproof membrane was tested according to GB / T328.20-2007 "Peel Performance of Asphalt Waterproof Membranes". The prepared polyurethane waterproof coating was mixed according to the specified ratio and applied in one coat using a 300mm×200mm×20mm cement mortar board. The coating thickness was 1.5mm. The waterproof membrane was then adhered after 1 hour. After curing under standard test conditions for 7 days, the peel strength was tested. The test results are shown in Table 1.
[0032] Table 1 project Example 1 Example 2 Comparative Example 1 Comparative Example 2 Surface drying time / min 8 5 9 10 Actual working time / min 18 16 20 25 Anti-sagging / mm 0mm, no wrinkles 0mm, no wrinkles flowing 0mm, no wrinkles Peel strength (N / mm) of self-adhesive modified bitumen rolls with polyester tires 1.75 1.58 1.57 1.06 Peel strength of TPO rolls (N / mm) 1.42 1.28 1.35 0.48
[0033] Comparing Example 1 and Comparative Example 1 above, it can be seen that when the main components of both are the same, the anti-sagging performance of Comparative Example 1, which does not contain the first and second additives, cannot meet the standard. Test results show that the bio-based polyurethane waterproof coating of the present invention has excellent anti-sagging effect and can cure quickly (the product achieves surface dryness within 5-9 minutes and complete dryness within 14-18 minutes); furthermore, the bio-based polyurethane waterproof coating of the present invention has better adhesion to asphalt waterproof membranes and polymer waterproof membranes than Comparative Example 2.
[0034] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A bio-based polyurethane waterproof coating, characterized in that, It consists of component A and component B in parts by mass; Component A consists of the following components: 50-85 parts of bio-based resin polyol; 15-35 parts isocyanate; First adjuvant: 0.9-2 parts; Component B consists of the following components: 25-45 parts of bio-based resin polyol; 5-15 parts of petroleum asphalt; Plasticizer 8-20 parts; 35-55 parts of filler; Chain extender 2-5 parts; Catalyst 0.1~0.5 parts; Second adjuvant: 0.8-2 parts; 0.1-2 parts of dehydrating agent; The first additive is diphenylmethane diisocyanate or phenyl dimethyl isocyanate; the second additive is a di-polyetheramine or a ternary polyetheramine; the waterproof coating does not contain organic solvents.
2. The bio-based polyurethane waterproof coating according to claim 1, characterized in that: The bio-based resin polyols in components A and B may be the same or different, and are selected from one or more of castor oil, modified castor oil hydroxyl-terminated resin, modified soybean oil hydroxyl-terminated resin, and modified palm oil hydroxyl-terminated resin.
3. The bio-based polyurethane waterproof coating according to claim 1, characterized in that: The filler is selected from one or more of the following: talc powder, kaolin, mica powder, calcium carbonate, and wollastonite, which have been activated by chemical coating.
4. The bio-based polyurethane waterproof coating according to claim 1, characterized in that: The catalyst is an organotin catalyst or an organobismuth catalyst.
5. The bio-based polyurethane waterproof coating according to claim 1, characterized in that: The plasticizer is selected from one or more of chlorinated paraffin, trioctyl phosphate, diphenyltoluene phosphate, diphenylisodecyl phosphate, dimethyl methyl phosphate, diethyl ethyl phosphate, tri(2-chloropropyl) phosphate, and tri(2-chloroethyl) phosphate.
6. The bio-based polyurethane waterproof coating according to claim 1, characterized in that: The chain extender is selected from one or more of dimethylthiotoluene diamine, 4,4'-di(alkylamino)-diphenylmethane, N,N'-dialkylphenyldiamine, 4,4'-di(alkylamino)-dicyclohexylmethane, and polyaspartic acid esters prepared by the Michael addition reaction of dialkyl maleate esters and aliphatic primary diamines.
7. The bio-based polyurethane waterproof coating according to claim 1, characterized in that: The dehydrating agent is selected from one or more of calcium oxide, magnesium oxide, and vinylalkoxysilane coupling agents.
8. A method for preparing a bio-based polyurethane waterproof coating, characterized in that, The process includes the following steps: the two-component waterproof coating consists of component A and component B; The manufacturing method of component A includes the following steps: adding polyether polyol to a reaction vessel, purging with nitrogen for protection, heating to above 80°C, adding isocyanate, stirring and mixing at 70~90°C for at least 1 hour, then cooling to 60°C, adding the first auxiliary agent, and continuing to stir for at least 10 minutes to obtain component A. The manufacturing method of component B includes the following steps: adding bio-based resin polyol, plasticizer and chain extender to a reaction vessel, purging with nitrogen for protection, heating to 70-90℃, then adding petroleum asphalt, and after the petroleum asphalt melts, adding filler and dispersing for at least 30 minutes. The material is then transferred to another reaction vessel via a grinding pump. After determining the moisture content, the corresponding dehydrating agent is added and stirred for 10-30 minutes. A catalyst and a second auxiliary agent are added and stirred for 10-30 minutes to obtain component B.