Single-component polyurethane leaking stoppage sealing material capable of foaming when meeting water and preparation method of single-component polyurethane leaking stoppage sealing material

Abstract

The invention relates to the technical field of sealing materials, and provides a single-component water-foaming type polyurethane leaking stoppage sealing material and a preparation method thereof.The single-component water-foaming type polyurethane leaking stoppage sealing material is prepared from, by weight, 100 parts of NOC end sealing prepolymer, 0.5-2 parts of catalyst A, 0.5-2 parts of surfactant, 1-3 parts of waterproof agent and 0.2-1 part of stabilizer; the NOC-terminated prepolymer is obtained by reacting polyether polyol, epoxy modified polyol and isocyanate; the epoxy modified polyol is prepared by mixing epoxy resin, polyol and an initiator and then reacting; the epoxy resin comprises bisphenol A type epoxy resin and bisphenol F type epoxy resin. According to the technical scheme, the problem of low strength of a polyurethane leaking stoppage sealing material in related technologies is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of sealing materials, and specifically, to a one-component water-expandable polyurethane leak stoppage and sealing material and a preparation method thereof. Background Art

[0002] Polyurethane foam leak stoppage material is a polymer material made by reacting raw materials such as isocyanate with polyether or polyester polyol. When in use, the polyurethane foam material will undergo a chemical reaction under the action of moisture or humidity, generating a large amount of foam. The foam expands rapidly and fills holes or cracks, thereby achieving the purpose of quickly stopping leaks.

[0003] Traditional one-component foaming polyurethane materials often face deficiencies such as insufficient strength, too high dry shrinkage rate, and low foaming ratio during construction in high-pressure or dynamic water environments, and even lead to secondary leakage or sealing failure. Therefore, it is necessary to develop a one-component polyurethane foam leak stoppage material with high strength, low dry shrinkage rate, and high foaming ratio to meet the requirements of engineering applications. Summary of the Invention

[0004] The present invention provides a one-component water-expandable polyurethane leak stoppage and sealing material and a preparation method thereof, which solves the problem of low strength of polyurethane leak stoppage and sealing materials in related technologies.

[0005] The technical solution of the present invention is as follows: The present invention provides a one-component water-expandable polyurethane leak stoppage and sealing material, which comprises raw materials in the following parts by weight: 100 parts of NOC-terminated prepolymer, 0.5 - 2 parts of catalyst A, 0.5 - 2 parts of surfactant, 1 - 3 parts of waterproofing agent, 0.2 - 1 part of stabilizer; the NOC-terminated prepolymer is obtained by reacting polyether polyol, epoxy-modified polyol with isocyanate; the epoxy-modified polyol is prepared by reacting epoxy resin, polyol, and initiator; the epoxy resin includes bisphenol A epoxy resin and bisphenol F epoxy resin.

[0006] As a further technical solution, the isocyanate is composed of diisocyanate and polyisocyanate.

[0007] In the polyurethane reaction process, isocyanate is a key raw material. The type and dosage of isocyanate will affect the rate of polyurethane, and the addition of isocyanate affects the quality of the leak stoppage material.

[0008] As a further technical solution, the diisocyanate includes one or more of isophorone diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, and the polyisocyanate includes polymethylene polyphenyl polyisocyanate.

[0009] In the present invention, the diisocyanate has two isocyanate groups and the reaction is relatively mild. The polyisocyanate contains multiple isocyanate groups and has high reaction activity, enabling it to react quickly with the polyol. By using the diisocyanate and polyisocyanate in combination, the reaction rate can be well controlled, avoiding a decrease in material properties caused by too fast a reaction and an impact on construction efficiency due to too slow a reaction.

[0010] As a further technical solution, the mass ratio of the diisocyanate to the polyisocyanate is 1:4 - 6.

[0011] As a further technical solution, the mass ratio of the bisphenol A epoxy resin to the bisphenol F epoxy resin is 1:1 - 2.

[0012] As a further technical solution, the preparation method of the epoxy-modified polyol includes the following steps: After mixing the polyol, epoxy resin, and catalyst B, the temperature is raised at a rate of 2 - 3 °C / min to 100 - 120 °C for 2 - 4 h for ring-opening reaction, and then the temperature is lowered to 80 - 90 °C for vacuum degassing and defoaming to obtain the epoxy-modified polyol.

[0013] As a further technical solution, the weight ratio of the epoxy resin to the polyol is 10:1 - 5.

[0014] As a further technical solution, the solvent includes one or both of ethanol and xylene.

[0015] As a further technical solution, the mass of the solvent is 3% - 15% of the total mass of the epoxy resin, polyol, and catalyst B, preferably 5% - 10%.

[0016] As a further technical solution, the addition amount of catalyst B is 0.1% - 0.5% of the mass of the epoxy resin.

[0017] As a further technical solution, catalyst B is boron trifluoride diethyl ether.

[0018] As a further technical solution, the vacuum degree during vacuum degassing and defoaming is -0.08 MPa, and the time for vacuum degassing and defoaming is 1 h.

[0019] As a further technical solution, the preparation method of the NOC-terminated prepolymer includes the following steps: After raising the temperature of the polyether polyol and the epoxy-modified polyol to 60 - 70 °C, isocyanate is added and reacted at 80 - 90 °C for 2 - 3 h to obtain the NOC-terminated prepolymer.

[0020] As a further technical solution, the mass ratio of the polyether polyol to the epoxy-modified polyol is 4:1.

[0021] As a further technical solution, the addition amount of the isocyanate is 50% - 70% of the sum of the masses of the polyether polyol and the epoxy-modified polyol, preferably 55% - 65%.

[0022] As a further technical solution, the isocyanate is added in three batches. The first batch is 50% by weight of the diisocyanate, the second batch is 50% by mass of the polyisocyanate and the remaining diisocyanate, and the third batch is the remaining polyisocyanate.

[0023] In the present invention, adding the isocyanate in batches can avoid the release of a large amount of heat during the reaction, the rapid increase in the temperature of the reaction system, improve the safety during the preparation process, and defining the addition order of the isocyanate can improve the stability during the material preparation process, make the material more uniform and regular, and better improve the compressive strength of the material.

[0024] As a further technical solution, it further includes at least one of the following technical features: The catalyst A includes an amine catalyst and an organotin catalyst; The surfactant is a silicone surfactant; The waterproof agent is a silicone waterproof agent; As a further technical solution, the catalyst A is composed of an amine catalyst and an organotin catalyst with a mass ratio of 3 - 5:2.

[0025] The amine catalyst and the organotin catalyst have different catalytic active centers and action mechanisms. The amine catalyst mainly has a good catalytic effect on the reaction of isocyanate with water, can promote the release of carbon dioxide gas, and make the foam expand. The organotin catalyst has a higher catalytic activity for the reaction of isocyanate with hydroxyl group, can accelerate the polyurethane chain growth reaction, and promote the formation of the polymer network. Using the two in combination can make the catalyst play its advantages at different reaction stages, synergistically accelerate the progress of the polyurethane reaction, shorten the reaction time, improve the production efficiency, and meet the requirements of the application scenario.

[0026] As a further technical solution, the amine catalyst is selected from one or more of triethylenediamine and dimethylaminoethanol, and the organotin catalyst is selected from one or more of dibutyltin dilaurate and dibutyltin diacetate.

[0027] As a further technical solution, the silicone surfactant includes one or more of polydimethylsiloxane and methylphenyl silicone oil.

[0028] The present invention also provides a preparation method of a one-component water-expandable polyurethane leak-sealing and plugging material, which includes the following steps: mixing the raw materials of the one-component water-expandable polyurethane leak-sealing and plugging material to obtain the polyurethane leak-sealing and plugging material.

[0029] The working principle and beneficial effects of the present invention are as follows: In the present invention, bisphenol A epoxy resin and bisphenol F epoxy resin are used to modify polyol, and the obtained epoxy resin-modified polyol reacts with isocyanate to prepare an NCO-terminated prepolymer, and a suitable catalyst, surfactant, waterproofing agent and stabilizer are introduced therein. When the material comes into contact with external moisture (or humidity), it can quickly foam and expand and has the following advantages: (1) Single-component packaging, convenient to use, reducing on-site operation errors; (2) Fast initial foaming speed, capable of stopping water and plugging cracks in a short time; (3) High foaming ratio, capable of effectively filling pores and adhering to the substrate; (4) Low dry shrinkage rate, good dimensional stability after curing, not easy to generate secondary cracks, ≤1%; (5) High strength, meeting the plugging requirements under high pressure or dynamic water conditions, and can maintain excellent plugging effect under high-pressure dynamic water environment after curing; (6) Strong adaptability, applicable to various scenarios such as building structures, subway tunnels, and water conservancy projects. Specific embodiments

[0030] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of the present invention.

[0031] In the following examples and comparative examples: Stabilizer: DBTDA, Bayer of Germany; Organic silicon waterproofing agent, SH-120, Jiangsu Hongxin Chemical Industry; Organic silicon surfactant, Momentive L-580, Dow Corning; Polyether polyol: molecular weight 3000-4000, hydroxyl value 28-56 mgKOH / g, Shandong Bluestar Chemical Industry; Bisphenol A epoxy resin: E-03; Bisphenol F epoxy resin: NPEF-170; Polymethylene polyphenyl polyisocyanate, Wanhua PM200.

[0032] Example 1 A preparation method of a single-component water-expandable polyurethane plugging and sealing material, comprising the following steps: S1. Mix polyethylene glycol 1000, epoxy resin (composed of bisphenol A epoxy resin and bisphenol F epoxy resin with a mass ratio of 1:1), and boron trifluoride ethyl ether (the addition amount is 0.1% of the mass of the epoxy resin) in xylene (the addition amount is 5% of the sum of the masses of the epoxy resin, polyethylene glycol 1000, and boron trifluoride ethyl ether). Then, with a heating rate of 2 °C, heat up to 100 °C and react for 2 h. Cool down to 80 °C and conduct vacuum degassing and defoaming for 1 h (vacuum degree -0.08 MPa) to obtain epoxy-modified polyol. The mass ratio of the epoxy resin to polyethylene glycol 1000 is 10:1; S2. After heating 80 parts of polyether polyol and 20 parts of epoxy-modified polyol to 60 °C, add 55 parts of polymethylene polyphenyl polyisocyanate and react at 80 °C for 3 h to obtain an NOC-terminated prepolymer; S3. After mixing 100 parts of the NOC-terminated prepolymer, 0.5 part of a catalyst (composed of triethylenediamine and dibutyltin dilaurate with a mass ratio of 3:2), 0.5 part of an organosilicon surfactant, 1 part of an organosilicon waterproofing agent, and 0.2 part of a stabilizer, obtain a one-component water-foaming polyurethane leak-sealing material.

[0033] Example 2 A preparation method of a one-component water-foaming polyurethane leak-sealing material, comprising the following steps: S1. Mix polyethylene glycol 1000, epoxy resin (composed of bisphenol A epoxy resin and bisphenol F epoxy resin with a mass ratio of 1:1), and boron trifluoride ethyl ether (the addition amount is 0.5% of the mass of the epoxy resin) in xylene (the addition amount is 5% of the sum of the masses of the epoxy resin, polyol 1000, and boron trifluoride ethyl ether). Then, with a heating rate of 3 °C, heat up to 120 °C and react for 2 h. Cool down to 90 °C and conduct vacuum degassing and defoaming for 1 h (vacuum degree -0.08 MPa) to obtain epoxy-modified polyol. The mass ratio of the epoxy resin to polyethylene glycol 1000 is 10:5; S2. After heating 80 parts of polyether polyol and 20 parts of epoxy-modified polyol to 70 °C, add 65 parts of polymethylene polyphenyl polyisocyanate and react at 90 °C for 2 h to obtain an NOC-terminated prepolymer; S3. After mixing 100 parts of the NOC-terminated prepolymer, 2 parts of a catalyst (composed of triethylenediamine and dibutyltin dilaurate with a mass ratio of 5:2), 2 parts of an organosilicon surfactant, 3 parts of an organosilicon waterproofing agent, and 1 part of a stabilizer, obtain a one-component water-foaming polyurethane leak-sealing material.

[0034] Example 3 Compared with Example 1, the difference in this example is that the mass ratio of bisphenol A epoxy resin to bisphenol F epoxy resin is 1:2.

[0035] Example 4 Compared with Example 1, the difference in this example is that the mass ratio of bisphenol A epoxy resin to bisphenol F epoxy resin is 1:1.5.

[0036] Example 5 Compared with Example 1, the difference in this example is that the isocyanate is only diphenylmethane diisocyanate.

[0037] Example 6 Compared with Example 1, the difference in this example is that the isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:4.

[0038] Example 7 Compared with Example 1, the difference in this example is that the isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:5.

[0039] Example 8 Compared with Example 1, the difference in this example is that the isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:6.

[0040] Example 9 Compared with Example 7, the difference in this example lies in step S2. In this example: S2. After heating 80 parts of polyether polyol and 20 parts of epoxy-modified polyol to 60°C, 55 parts of isocyanate are added. The isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:5, and is added in two batches. After the first batch of diphenylmethane diisocyanate is added and reacted at 80°C for 1.5 h, the second batch of polymethylene polyphenyl polyisocyanate is added and reacted at 80°C for 1.5 h to obtain an NOC-terminated prepolymer.

[0041] Example 10 Compared with Example 7, the difference in this example lies in step S2. In this example: S2. After heating 80 parts of polyether polyol and 20 parts of epoxy-modified polyol to 60°C, 55 parts of isocyanate are added. The isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:5, and is added in two batches. After the first batch of polymethylene polyphenyl polyisocyanate is added and reacted at 80°C for 1.5 h, the second batch of diphenylmethane diisocyanate is added and reacted at 80°C for 1.5 h to obtain an NOC-terminated prepolymer.

[0042] Example 11 Compared with Example 7, the difference in this example lies in step S2. In this example: S2. After heating 80 parts of polyether polyol and 20 parts of epoxy-modified polyol to 60°C, 55 parts of isocyanate are added. The isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:5, and is added in three batches. The first batch adds 50% by weight of diphenylmethane diisocyanate and reacts at 80°C for 1 h, then the second batch adds 50% by mass of polymethylene polyphenyl polyisocyanate and reacts at 80°C for 1 h, and then the third batch adds the remaining diphenylmethane diisocyanate and the remaining polymethylene polyphenyl polyisocyanate and continues to react at 80°C for 1 h to obtain an NOC-terminated prepolymer.

[0043] Example 12 Compared with Example 7, the difference in this example lies in step S2. In this example: S2. After heating 80 parts of polyether polyol and 20 parts of epoxy-modified polyol to 60°C, 55 parts of isocyanate are added. The isocyanate is composed of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate with a mass ratio of 1:5, and is added in three batches. The first batch adds 50% by weight of diphenylmethane diisocyanate and reacts at 80°C for 1 h, then the second batch adds 50% by mass of polymethylene polyphenyl polyisocyanate and the remaining diphenylmethane diisocyanate and reacts at 80°C for 1 h, and then the third batch adds the remaining polymethylene polyphenyl polyisocyanate and continues to react at 80°C for 1 h to obtain an NOC-terminated prepolymer.

[0044] Comparative Example 1 Compared with Example 1, the difference in this comparative example is that the epoxy-modified polyol is replaced with an equal amount of polyether polyol.

[0045] Comparative Example 2 Compared with Example 1, the difference in this comparative example is that the epoxy resin is only bisphenol A epoxy resin.

[0046] Comparative Example 3 Compared with Example 1, the difference in this comparative example is that the epoxy resin is only bisphenol F epoxy resin.

[0047] Test Example 1 According to the measurement method in GB / T 8813-2020 "Determination of Compressive Properties of Rigid Polyurethane Foams", the compressive strength of the sealing materials in Examples 1 to 12 and Comparative Examples 1 to 3 was measured, and the measurement results are shown in Table 1.

[0048] Table 1 Compressive Strength of Sealing Materials in Examples 1 to 12 and Comparative Examples 1 to 3

[0049] As can be seen from Table 1, the compression strength of the sealing material of the present invention is as high as 11.2 MPa, far higher than that of Comparative Examples 1 to 3, which can meet the plugging requirements under high-pressure or dynamic water conditions and has excellent plugging compression strength.

[0050] Test Example 2 The foaming ratio, initial foaming time, curing time, and storage period of Examples 4, 7, 12, and Comparative Example 1 were measured according to the measurement method in JC / T 2041-2020 "Polyurethane Grouting Material", and the measurement results are shown in Table 2; Table 2 Measurement Results of Sealing and Plugging Materials

[0051] As can be seen from Table 2, Example 12 of the present invention has a fast initial foaming speed, can stop water and plug cracks in a short time, and has a high foaming ratio, can effectively fill pores, and adheres to the substrate better to meet the requirements during use.

[0052] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, 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 one-component water-foamable polyurethane leak-proof sealing material, characterized in that: The raw materials include the following components in parts by weight: 100 parts of NOC end-capped prepolymer, 0.5-2 parts of catalyst A, 0.5-2 parts of surfactant, 1-3 parts of waterproofing agent, and 0.2-1 parts of stabilizer; the NOC end-capped prepolymer is obtained by reacting polyether polyol, epoxy-modified polyol and isocyanate; the epoxy-modified polyol is epoxy resin and polyol, which are obtained by ring-opening reaction under the action of catalyst B; the epoxy resin includes bisphenol A epoxy resin and bisphenol F epoxy resin.

2. A one-component water-foamable polyurethane leak-proof sealing material according to claim 1, characterized in that: The isocyanate is composed of diisocyanate and polyisocyanate.

3. The one-component water-foamable polyurethane leak-proof sealing material according to claim 1, characterized in that: The diisocyanate includes one or more of isophorone diisocyanate, toluene diisocyanate, and diphenylmethane diisocyanate, and the polyisocyanate includes polymethylene polyphenyl polyisocyanate.

4. The one-component water-foamable polyurethane leak-proof sealing material according to claim 1, characterized in that: The mass ratio of the diisocyanate to the polyisocyanate is 2:3-5.

5. The one-component water-foamable polyurethane leak-proof sealing material according to claim 1, characterized in that: The mass ratio of the bisphenol A epoxy resin to the bisphenol F epoxy resin is 1:1-2.

6. The one-component water-foamable polyurethane leak-proof sealing material according to claim 1, characterized in that: The preparation method of the epoxy-modified polyol comprises the following steps: after mixing the polyol, the epoxy resin and the catalyst B, heating the mixture to 100-120° C. at a heating rate of 2-3° C. / min and reacting for 2-4 hours to perform a ring-opening reaction, and cooling the mixture to 80-90° C. to perform vacuum degassing and defoaming to obtain the epoxy-modified polyol.

7. A one-component water-foamable polyurethane leak-proof sealing material according to claim 6, characterized in that: The mass ratio of the epoxy resin to the polyol is 10:1-5.

8. The one-component water-foamable polyurethane leak-proof sealing material according to claim 2, characterized in that: The method for preparing the NOC end-capped prepolymer comprises the following steps: heating a polyether polyol and an epoxy-modified polyol to 60-70° C., adding isocyanate and reacting at 80-90° C. for 2-3 hours to obtain the NOC end-capped prepolymer.

9. The one-component water-foamable polyurethane leak-proof sealing material according to claim 1, characterized in that: The isocyanate is added in three batches, the first batch is 50% by weight of diisocyanate, the second batch is 50% by weight of polyisocyanate and the remaining diisocyanate, and the third batch is the remaining polyisocyanate.

10. A method for preparing a one-component water-foamable polyurethane leak-proof sealing material, characterized in that: The method comprises the following steps: mixing the raw materials of the single-component water-foamable polyurethane plugging and sealing material described in any one of claims 1 to 9 to obtain the polyurethane plugging and sealing material.

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