Low-water-sensitivity polyurethane grouting material suitable for high-temperature environment and preparation method of low-water-sensitivity polyurethane grouting material

Abstract

The invention belongs to the field of polyurethane high polymer materials, and particularly relates to a low-water-sensitivity polyurethane grouting material suitable for a high-temperature environment and a preparation method of the low-water-sensitivity polyurethane grouting material. The grouting material comprises a component A and a component B in a mass part ratio of 1: 1. The component A is prepared from 20 to 30 parts of acrylate grafted polyether polyol, 40 to 60 parts of cashew nut shell oil polyether polyol, 5 to 15 parts of expandable microspheres, 1 to 3 parts of a catalyst, 1 to 3 parts of a plasticizer, 0.5 to 1.5 parts of a foam stabilizer, 1 to 3 parts of water and 10 to 20 parts of a flame retardant. And the component B is polyisocyanate. The low-water-sensitivity polyurethane grouting material provided by the invention can be quickly diffused in concrete crack pores in a high-temperature water bursting environment, and a formed consolidated body is high in strength, good in impermeability and capable of playing roles in water plugging and reinforcement.

Description

Technical Field

[0001] The invention belongs to the field of polyurethane polymer materials, and in particular relates to a low water-sensitivity polyurethane grouting material suitable for high-temperature environments and a preparation method thereof. Background Art

[0002] Concrete cracks are the most common defects in concrete structural engineering. Currently, the commonly used crack repair and reinforcement technologies mainly include physical repair technology and chemical grouting technology. Chemical grouting technology refers to burying grouting nozzles through drilling holes, using pressure pumps to inject chemical grouting materials into structural cracks, so that the slurry is injected into concrete gaps or rock formations, gradually diffuses, solidifies, and fully contacts with concrete, rocks, etc., to achieve the effects of plugging leaks, strengthening, and reinforcement.

[0003] As a chemical grouting material, polyurethane grouting material is widely used in various projects such as underground engineering plugging, building structure reinforcement, and mine engineering anti-seepage due to its advantages such as strong slurry penetration ability, simple construction process, excellent reinforcement and water blocking effect, and good filling and sealing effect. At present, the commonly used polyurethane grouting materials on the market are divided into single-component polyurethane grouting materials and two-component polyurethane grouting materials. The single-component polyurethane grouting material with prepolymer as the main component has the disadvantages of high viscosity and low strength after reaction with water, and the actual engineering application effect is general. The two-component polyurethane grouting material is composed of polyols, additives, etc. as the first component and isocyanate or terminal NCO prepolymer as the second component. It has the advantages of high strength, self-curing, good environmental protection, and convenient adjustment of curing time. It has been widely used in the treatment of engineering diseases such as coal mines, underground projects, trenchless repairs, and railways.

[0004] Relevant researchers have conducted a lot of research and development work on two-component polyurethane grouting materials. For example, patent CN115651153A discloses a flame-retardant two-component polyurethane grouting material and its preparation method. Through formula design, mixed polymer polyols with different functionalities are used to improve the crosslinking degree of the system, and aspartic acid ester resin is introduced to introduce urea bonds to improve the strength of the material. The prepared two-component grouting material can quickly foam and plug leaks when it comes into contact with water, solving the current problems of low strength and slow reaction of single-component polyurethane free foam. Patent CN110183607A discloses a two-component water-blocking reinforcement grouting material and its preparation method. Phthalic anhydride polyester polyol is introduced into component A, thereby improving the strength and toughness of the cured product. At the same time, the phthalic anhydride polyester polyol contains a polyester group with a large polarity, which improves the bonding performance of the cured product with the wet base surface; by introducing a latent curing agent into component A, the latent curing agent can quickly hydrolyze to generate an amino-terminated chain extender at low temperature, which can quickly react with isocyanate, thereby improving the reaction rate at low temperature. The material has low viscosity, high strength and good toughness of the cured product, which improves the plugging and reinforcement effect. Patent CN110183607A discloses a high-strength polyurethane grouting material. Through the design of the polyurethane prepolymer structure, the selection and adjustment of the ratio of chain extenders, plasticizers and additives, and the combination of an appropriate curing system, the prepared grouting material has the characteristics of high compressive strength, adjustable curing time, and convenient construction.

[0005] From the above description, it can be seen that the two-component polyurethane grouting materials that have been studied so far have many characteristics, but there are still some shortcomings. Two-component polyurethane grouting materials are greatly affected by temperature and moisture. In a high-temperature water-gushing environment, the material will expand and foam rapidly when it comes into contact with water, and the pores of the solidified body formed are relatively loose and the strength is relatively low; and the slurry solidifies too quickly and cannot penetrate into the cracks and pores, causing construction difficulties and poor sealing and reinforcement effects. In view of these shortcomings, the development of a low-water-sensitivity polyurethane grouting material suitable for high-temperature environments has become an urgent problem to be solved. Summary of the invention

[0006] The purpose of the present invention is to solve the above problems and provide a low water-sensitivity polyurethane grouting material suitable for high temperature environments, and a preparation method of the grouting material.

[0007] The low water-sensitivity polyurethane grouting material suitable for high-temperature environment and the preparation method thereof are characterized in that the grouting material comprises component A and component B, and the mass ratio thereof is 1:1, the component A comprises: 20 to 30 parts of acrylate grafted polyether polyol, 40 to 60 parts of cashew nut shell oil polyether polyol, 5 to 15 parts of expandable microspheres, 1 to 3 parts of catalyst, 1 to 3 parts of plasticizer, 0.5 to 1.5 parts of foam stabilizer, and 10 to 20 parts of flame retardant; the component B is polyisocyanate.

[0008] The acrylate grafted polyether polyol is prepared by free radical polymerization of acrylate and polyether polyol, the acrylate is lauryl methacrylate, and the polyether polyol is a polyether polyol based on PO-EO copolyether triol, with a hydroxyl value of 230-400 mg KOH / g.

[0009] The functionality of the cashew nut shell oil polyether polyol is 2-6, and the hydroxyl value is 400-700 mg KOH / g.

[0010] The expandable microspheres are core-shell structures with a thermoplastic polymer as the shell layer and liquid alkane gas (one or more of pentane, hexane, octane, and heptane) encapsulated inside. The diameter of the microspheres ranges from 50 to 100 μm, the glass transition temperature of the shell polymer ranges from 55 to 65° C., and the expansion ratio is 1.2 to 1.5.

[0011] The catalyst is one or more of a tertiary amine catalyst and an organic metal catalyst, and the organic metal catalyst includes one or more of organic tin, organic zirconium, and organic platinum; the organic metal catalyst preferentially catalyzes the reaction of alcohol hydroxyl group and polyisocyanate.

[0012] The foam stabilizer is a water-soluble organic silicone compound.

[0013] The polyisocyanate is polyphenyl polymethylene polyisocyanate (PAPI).

[0014] The low water-sensitivity polyurethane grouting material suitable for high temperature environment and the preparation method thereof are characterized by comprising the following steps: (1) The acrylate grafted polyether polyol, the cashew nut shell liquid polyether polyol, and the optional expandable microspheres, the catalyst, the plasticizer, the foam stabilizer, and the flame retardant are stirred at high speed and mixed uniformly to obtain the component A.

[0015] (2) Component A and component B are mixed in a mass ratio of 1:1 to obtain the low water-sensitivity polyurethane grouting material.

[0016] The low water-sensitivity polyurethane grouting material suitable for high-temperature environments is used in grouting and plugging high-temperature water gushing in tunnels.

[0017] The positive effects of the low water-sensitivity polyurethane grouting material suitable for high temperature environment provided by the present invention are: The acrylate grafted polyether polyol in the low water-sensitivity polyurethane grouting material provided by the present invention contains a long-chain alkyl group, which has good hydrophobicity compared to ordinary polyether polyols. The cashew nut shell oil polyether polyol has a cardanol fatty long chain compared to ordinary polyether polyols, has good hydrophobicity, and can maintain low water sensitivity during the curing process with isocyanate, reduce the foaming ratio, and thus improve the mechanical properties of the final polyurethane system. In addition, the cashew nut shell oil polyether polyol has a fast curing speed with isocyanate and has an aromatic structure. The dispersion force of the benzene ring structure can exclude water molecules bound to the substrate surface, enhance the slurry infiltration effect, and further improve the adhesion at the wet substrate interface.

[0018] Another positive effect of the present invention is that the expandable microspheres provided are microspheres with a core-shell structure, which are made of a thermoplastic polymer as a shell layer and a low-boiling alkane liquid as a core, and are characterized by low cost and easy processing. The thermoplastic polymer shell forms a complete seal for the enclosed volatile substances. When the microspheres are heated, the thermoplastic shell layer of the microspheres softens, and at the same time, the volatile substances at the core are vaporized or decomposed by heat to form gas, which increases the pressure inside the microspheres. The effects of the two together cause the volume of the microspheres to expand, thereby filling and reinforcing the polyurethane, enhancing the strength of the polyurethane consolidation body, improving the material's anti-seepage performance, and enhancing the actual plugging and reinforcement effect of the polyurethane grouting material. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below with reference to the embodiments. Example

[0020] (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (hydroxyl value 230 mg KOH / g), 20 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 60 parts; Expandable microspheres (microsphere diameter is about 50 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.2), 5 parts; Catalyst, 1 part; Plasticizer, 1 part; Foam stabilizer, 0.5 parts; Flame retardant, 10 parts.

[0021] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0022] The mass ratio of component A to component B is 1:1.

[0023] (ii) The preparation steps include: (1) A certain amount of acrylate grafted polyether polyol, cashew nut shell liquid polyether polyol, expandable microspheres, catalyst, plasticizer, foam stabilizer, and flame retardant are stirred at high speed and mixed uniformly to obtain component A.

[0024] (2) Component A and component B are fully mixed to obtain a low water-sensitive polyurethane grouting material. Example

[0025] (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 3, hydroxyl value 500 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 50 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.2), 10 parts; Catalyst, 3 parts; Plasticizer, 1 part; Foam stabilizer, 1 part; Flame retardant, 20 parts.

[0026] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0027] The mass ratio of component A to component B is 1:1.

[0028] (ii) The preparation steps are the same as those in Example 1. Example

[0029] (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 100 μm, shell polymer glass transition temperature range is 55-65°C, expansion ratio is 1.5), 15 parts; Catalyst, 1 part; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0030] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0031] The mass ratio of component A to component B is 1:1.

[0032] (ii) The preparation steps are the same as those in Example 1. Example

[0033] (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 50 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.3), 10 parts; Catalyst, 3 parts; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0034] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0035] The mass ratio of component A to component B is 1:1.

[0036] (ii) The preparation steps are the same as those in Example 1.

[0037] Comparative Example 1: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 2, hydroxyl value 370 mg KOH / g), 5 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 60 parts; Expandable microspheres (microsphere diameter is about 50 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.2), 5 parts; Catalyst, 1 part; Plasticizer, 1 part; Foam stabilizer, 0.5 parts; Flame retardant, 10 parts.

[0038] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0039] The mass ratio of component A to component B is 1:1.

[0040] (ii) The preparation steps are the same as those in Example 1.

[0041] Comparative Example 2: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 3, hydroxyl value 500 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol, 20 parts; Expandable microspheres (microsphere diameter is about 50 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.2), 10 parts; Catalyst, 3 parts; Plasticizer, 1 part; Foam stabilizer, 1 part; 20 parts of flame retardant.

[0042] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0043] The mass ratio of component A to component B is 1:1.

[0044] (ii) The preparation steps are the same as those in Example 1.

[0045] Comparative Example 3: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; expandable microspheres, 0 parts; Catalyst, 1 part; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0046] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0047] The mass ratio of component A to component B is 1:1.

[0048] (ii) The preparation steps are the same as those in Example 1.

[0049] Comparative Example 4: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 100 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.5), 20 parts; Catalyst, 3 parts; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0050] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0051] The mass ratio of component A to component B is 1:1.

[0052] (ii) The preparation steps are the same as those in Example 1.

[0053] Comparative Example 5: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 10 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.3), 10 parts; Catalyst, 3 parts; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0054] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0055] The mass ratio of component A to component B is 1:1.

[0056] (ii) The preparation steps are the same as those in Example 1.

[0057] Comparative Example 6: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 400 μm, shell polymer glass transition temperature range is 55-65 ° C, expansion ratio is 1.3), 10 parts; Catalyst, 3 parts; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0058] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0059] The mass ratio of component A to component B is 1:1.

[0060] (ii) The preparation steps are the same as those in Example 1.

[0061] Comparative Example 7: (I) The mass fractions of each raw material in the polyurethane grouting material are: Component A: Acrylate grafted polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 30 parts; Cashew nut shell liquid polyether polyol (functionality 4, hydroxyl value 600 mg KOH / g), 50 parts; Expandable microspheres (microsphere diameter is about 50 μm, shell polymer glass transition temperature range is 55~65℃, expansion ratio is 1.3), 10 parts; Catalyst, 6 parts; Plasticizer, 1 part; Foam stabilizer, 1.5 parts; Flame retardant, 20 parts.

[0062] Component B: Polyisocyanate polyphenyl polymethylene polyisocyanate (PAPI).

[0063] The mass ratio of component A to component B is 1:1.

[0064] (ii) The preparation steps are the same as those in Example 1.

[0065] Effect description: According to Examples 1-4 and Comparative Examples 1-7, polyurethane grouting materials were prepared, and the setting time and foaming ratio of the polyurethane grouting materials under the same 60°C high temperature and water-rich environment conditions, and the compressive strength of the formed polyurethane solid body were tested with reference to the standard JC / T 2041-2020 "Polyurethane Grouting Materials"; the bonding strength between the polyurethane grouting materials and the wet concrete base was tested with reference to the standard GB / T 16777 2008 "Test Methods for Building Waterproof Coatings". The test results are shown in Table 1.

[0066] Table 1 Performance test results of polyurethane grouting materials prepared in Examples 1-4 and Comparative Examples 1-7

[0067] It can be seen from the data in Table 1 that the polyurethane grouting materials prepared in Examples 1-4 have obvious advantages over the comparative example.

[0068] The long dodecyl chain in the acrylate grafted polyether polyol has multiple non-polar bonds such as carbon-carbon bonds and carbon-hydrogen bonds, which makes it non-polar as a whole, and the interaction force between it and polar water molecules is very weak; in addition, due to the steric hindrance effect and the van der Waals force, the long-chain alkyl groups tend to aggregate with each other, showing good hydrophobicity. The introduction of an appropriate proportion of acrylate grafted polyether polyol can increase the number of long-chain alkyl groups in the system, increase the proportion of hydrophobic groups, reduce the reaction rate and self-foaming ratio of the polyurethane grouting material with external water in a water-rich environment, and improve the strength of the material. Compared with Example 1, the mass fraction of acrylate grafted polyether polyol in Comparative Example 1 is too small, the foaming ratio of the polyurethane grouting material is high, the bubble size is unstable, and the strength of the solid body is low, which cannot meet the requirements of practical applications.

[0069] Compared with ordinary polyether polyols, cashew nut shell oil polyether polyols have cardanol fatty long chains, have good hydrophobicity, and can maintain low water sensitivity during curing with isocyanate, reduce foaming ratio, thereby improving the mechanical properties of the final polyurethane system. In addition, cashew nut shell oil polyether polyols and isocyanate cure fast, and have aromatic structures, and the dispersion force of the benzene ring structure can exclude water molecules bound to the substrate surface, enhance the slurry infiltration effect, and further improve the interfacial adhesion. Compared with Example 2, the amount of cashew nut shell oil polyether polyol added in Comparative Example 2 is insufficient, and the compressive strength and bonding strength of the polyurethane grouting material formed are both low.

[0070] Under high temperature environment, when the expandable microspheres are heated, when the heating temperature is higher than the boiling point of the alkane gas coated by the microspheres and reaches the glass transition temperature of the microsphere polymer shell, the microsphere shell softens and becomes plastic, and the gas inside the microspheres gasifies to increase the internal pressure of the microspheres, causing expansion, forming a microsphere filling material with certain elasticity and airtightness, which plays a role in reinforcing the polyurethane grouting material. Compared with Example 3, no expandable microspheres were added in Comparative Example 3, which could not play a role in reinforcing, and the strength of the consolidated body was low. In Comparative Example 4, the amount of expandable microspheres added was too much, resulting in an excessively large overall viscosity of the polyurethane grouting material, affecting the grouting effect.

[0071] Compared with Example 4, the diameter of the expandable microspheres in Comparative Example 5 is too small, and they cannot achieve a good filling effect after thermal expansion; the diameter of the expandable microspheres in Comparative Example 6 is too large, and since the individual microspheres occupy a large space, it is difficult for them to be densely stacked and filled into the tiny pores of polyurethane like small-sized microspheres, resulting in poor internal filling density of the polyurethane grouting material and average filling and reinforcement effect.

[0072] Compared with Example 4, the amount of catalyst added in Comparative Example 7 is too high. Due to the fast reaction speed, there are defects such as uneven pore size, thin pore wall, poor stability, etc., and the overall strength is low.

[0073] In summary, within the scope of the formula claimed in the present invention, the performance of the polyurethane grouting material in all aspects can meet the requirements. When the formula exceeds the scope of the present invention, some performances of the polyurethane grouting material will be obviously insufficient.

Claims

1. A low water-sensitivity polyurethane grouting material suitable for high temperature environment and a preparation method thereof, characterized in that The grouting material comprises component A and component B, and the mass ratio thereof is 1:

1. The component A comprises: 20-30 parts of acrylate grafted polyether polyol, 40-60 parts of cashew nut shell oil polyether polyol, 5-15 parts of expandable microspheres, 1-3 parts of catalyst, 1-3 parts of plasticizer, 0.5-1.5 parts of foam stabilizer, and 10-20 parts of flame retardant; the component B is polyisocyanate.

2. The low water sensitivity polyurethane grouting material suitable for high temperature environment according to claim 1, characterized in that The acrylate grafted polyether polyol is prepared by free radical polymerization of acrylate and polyether polyol, the acrylate is lauryl methacrylate, and the polyether polyol is a polyether polyol based on PO-EO copolyether triol, with a hydroxyl value of 230-400 mg KOH / g.

3. The low water sensitivity polyurethane grouting material suitable for high temperature environment according to claim 1, characterized in that The functionality of the cashew nut shell oil polyether polyol is 2-6, and the hydroxyl value is 400-700 mg KOH / g.

4. The low water sensitivity polyurethane grouting material suitable for high temperature environment according to claim 1, characterized in that The expandable microspheres are core-shell structures with a thermoplastic polymer as the shell layer and liquid alkane gas (one or more of pentane, hexane, octane, and heptane) encapsulated inside. The diameter of the microspheres ranges from 50 to 100 μm, the glass transition temperature of the shell polymer ranges from 55 to 65° C., and the expansion ratio is 1.2 to 1.

5.

5. The low water sensitivity polyurethane grouting material suitable for high temperature environment according to claim 1, characterized in that The catalyst is one or more of a tertiary amine catalyst and an organic metal catalyst, and the organic metal catalyst includes one or more of organic tin, organic zirconium, and organic platinum; the organic metal catalyst preferentially catalyzes the reaction of alcohol hydroxyl group and polyisocyanate.

6. The low water sensitivity polyurethane grouting material suitable for high temperature environment according to claim 1, characterized in that The foam stabilizer is a water-soluble organic silicone compound.

7. The low water sensitivity polyurethane grouting material suitable for high temperature environment according to claim 1, characterized in that The polyisocyanate is polyphenyl polymethylene polyisocyanate (PAPI).

8. The low water-sensitivity polyurethane grouting material suitable for high temperature environment and the preparation method thereof according to claim 1, characterized in that The following steps are involved: (1) stirring the acrylate grafted polyether polyol, cashew nut shell liquid polyether polyol, and optionally expandable microspheres, a catalyst, a plasticizer, a foam stabilizer, and a flame retardant at high speed to obtain the component A; (2) Component A and component B are mixed in a mass ratio of 1:1 to obtain the low water-sensitivity polyurethane grouting material.

9. Use of the low water-sensitivity polyurethane grouting material suitable for high-temperature environments according to claims 1-7 in grouting and plugging of high-temperature water inrush in tunnels.

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