Synthesis and preparation method of low-viscosity and high-strength modified epoxy resin grouting material

Abstract

The invention provides a low-viscosity and high-strength modified epoxy resin grouting material which is mainly prepared from a component A and a component B in a mass ratio of (2: 1)-(3: 1) during use, carboxyl-terminated modified epoxy resin is adopted, and a carboxyl group with strong hydrophilicity and a hydroxyl group generated in the modification process are introduced into an epoxy resin molecular chain, so that the high-strength modified epoxy resin grouting material is obtained. According to the epoxy resin grouting material and the preparation method thereof, the affinity of the epoxy resin grouting material to water molecules is greatly enhanced, hydrophilic groups of modified epoxy molecules extend into a water covering layer in a crack of a building body, the defect that an existing grouting material is incompatible with the water covering layer is overcome, the surfactant contains a defoaming polysiloxane component, particles can be uniformly dispersed in a mixture, and the grouting effect is improved. A good dispersion effect is achieved; the silane coupling agent is added, so that the performance and the bonding strength of the epoxy resin grouting material are also improved.

Description

Technical Field

[0001] This invention relates to the field of chemical grouting technology for building materials, specifically to an epoxy resin grouting material for structural reinforcement in humid environments and its preparation method. Background Technology

[0002] While infrastructure construction such as cross-sea bridges, subway tunnels, and highway culverts fuels my country's economic growth, it also leads to a surge in investment in building maintenance. Concrete materials frequently crack due to early shrinkage, thermal shrinkage or expansion, settlement, and accidental overloading. Cracks compromise structural integrity, load-bearing capacity, and durability, and allow water and other corrosive media to penetrate the concrete matrix, leading to further crack development, steel corrosion, and structural failure. "A thousand-mile dike can be destroyed by an ant hole"—even minute cracks can significantly increase the permeability of concrete, substantially impacting structural durability.

[0003] Grouting is the most effective way to reduce the permeability of concrete and restore the structural load-bearing capacity. However, there are many types of grouting materials available, and their performance varies greatly.

[0004] (1) Water glass grouting materials: Water glass is an aqueous solution of soluble alkali metal silicate. Its solidification product SiO2 can react with alkaline oxides. Therefore, water glass grouting materials are susceptible to acid and alkali corrosion and the effects of wet and dry cycles. Its water resistance, alkali resistance and durability are poor, and it cannot be used in humid environments.

[0005] (2) Acrylic acid grouting materials: Grouting materials with acrylate as the main agent have low cross-linking density after curing, are elastic, and have good resistance to deformation. However, the cured material has poor rigidity and low strength, making it difficult to achieve the effect of structural reinforcement in the field of concrete crack repair.

[0006] (3) Polyurethane grouting materials: Based on the reactivity of the -NCO group, they release a large amount of carbon dioxide gas after curing with the concrete matrix or water in the air. After curing, pores are easily generated in the adhesive layer or defects are formed at the polyurethane-concrete interface. This leads to a decrease in the mechanical strength and sealing performance of the polyurethane-concrete repair system, which has an adverse effect on the durability of the concrete structure.

[0007] (4) Epoxy resin grouting material: The reaction between amino and epoxy groups can increase the hydroxyl value of the epoxy curing system and improve the bonding strength of the grouting material; the reactive diluent reduces the viscosity of the epoxy resin grouting material, increases the grouting capacity of the epoxy grout, and overcomes the problem of organic gas release generated by traditional reactive diluents; in the epoxy-amine curing system, the coupling agent molecule is introduced into the cross-linking network structure of the epoxy resin, and the silane group generated after dehydration reacts with the hydration products of concrete to form a Si-O-inorganic surface, so that the organic epoxy curing material and the inorganic matrix form a covalent bond connection, which improves the mechanical properties of the epoxy-concrete interface.

[0008] Given the superior performance of traditional epoxy resin grouting materials in organic concrete repair and their shortcomings in repairing concrete cracks in humid environments, there is an urgent need for a modified epoxy resin grouting material that can effectively bond and cure the water-covered layer at the interface of damp concrete and penetrate into the building substrate. Summary of the Invention

[0009] For this purpose, it is necessary to provide an epoxy resin grouting material for concrete cracks in humid environments and its preparation method, so as to solve the problem that existing grouting materials cannot effectively repair concrete crack surfaces with water-covered layers.

[0010] This invention provides a low-viscosity, high-strength modified epoxy resin grouting material, mainly composed of component A and component B, used in a mass ratio of 2:1 to 3:1. Component A and component B include the following raw materials: A modified epoxy resin grouting material, characterized in that the sealant comprises component A and component B, wherein component A comprises the following raw materials in parts by weight: 70-100 parts of carboxyl-terminated modified epoxy resin 20-30 parts of reactive diluent 5-8 parts of coupling agent 2-6 parts toughening agent 1-3 parts surfactant; Component B comprises the following raw materials: 45-50 parts of modified polyamide 45-50 parts of alicyclic amine Curing accelerator 1 to 10 parts.

[0011] The modified epoxy resin grouting material is characterized in that the carboxyl-terminated modified epoxy resin of component A is an anionic hydrophilic epoxy resin modified with dicarboxylic acid, and its epoxy value is 0.40-0.47; in some embodiments, the raw material components used in the modification of the carboxyl-terminated modified epoxy resin include dicarboxylic acid, bisphenol A type epoxy resin and catalyst, and the mass fraction ratio of the dicarboxylic acid, bisphenol A type epoxy resin and catalyst is 0.8:1:0.05.

[0012] The modified epoxy resin grouting material according to claim 1 is characterized in that the dicarboxylic acid includes at least one of oxalic acid, malonic acid, succinic acid, glutaric acid, azelaic acid, isophthalic acid, phthalic acid, terephthalic acid, and dimethyl terephthalate; preferably oxalic acid or azelaic acid; The bisphenol A epoxy resin is of at least one of E-32, E42, E44, E51 and E55; preferably E44 or E51; the catalyst is of at least one of benzyltriethylammonium chloride, tetrabutylammonium bromide and 1-butyl-3-methylimidazolium bromide; preferably benzyltriethylammonium chloride; The active diluent of component A is an aliphatic polyepoxy glycidyl ether; it includes at least one of alkyl glycidyl ether, butyl glycidyl ether, benzyl glycidyl ether, polypropylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, and butylene glycol diglycidyl ether; preferably benzyl glycidyl ether or polypropylene glycol diglycidyl ether. The coupling agent of component A is a silane coupling agent containing an epoxy group or an amino functional group in its molecule, including at least one of γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-glycidyl etheroxypropyltriethoxysilane and N,N-diethyl-3-aminopropyltrimethoxysilane; preferably γ-aminopropyltrimethoxysilane.

[0013] The modified epoxy resin grouting material is characterized in that the toughening agent of component A is an active toughening agent, which includes at least one of liquid polysulfide rubber, liquid nitrile rubber, liquid chloroprene rubber, and liquid polyether; preferably liquid nitrile rubber.

[0014] The modified epoxy resin grouting material is characterized in that the surfactant of component A is a low-foaming, high-penetration nonionic surfactant, which includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid polyoxyethylene ester, polyoxyethylene alkylamine and polyoxyethylene alkylamide; preferably fatty alcohol polyoxyethylene ether. The modified polyamide of component B is a diacid-modified low-viscosity polyamide with an amine value of 300-350 mgKOH / g; in some embodiments, the raw material components used in the modification of the low-viscosity polyamide include diacid and polyamine, and the mass fraction ratio of the diacid to the polyamine is 1:2. The dicarboxylic acid includes at least one of oxalic acid, malonic acid, succinic acid, glutaric acid, azelaic acid, adipic acid, isophthalic acid, phthalic acid, terephthalic acid, and benzoic acid; preferably adipic acid.

[0015] The modified epoxy resin grouting material is characterized in that the curing agent raw material is a polyamine, including at least one of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diallyltriamine, and triethylenediamine; preferably diethylenetriamine or triethylenetetramine.

[0016] The modified epoxy resin grouting material is characterized in that the alicyclic amine in component B includes 1,3-cyclohexanedimethylamine and 4,4-cyclohexanedimethylamine. ， -At least one of diaminodicyclohexylmethane, cyclohexyldimethylamine and isophorone diamine; preferably 1,3-cyclohexyldimethylamine or isophorone diamine.

[0017] The modified epoxy resin grouting material is characterized in that the curing accelerator of component B includes at least one of diethanolamine, triethanolamine, triethylamine, m-phenylenediamine, diaminephenylmethane, and 2,4,6-tris(dimethylaminomethyl)phenol; preferably triethanolamine or 2,4,6-tris(dimethylaminomethyl)phenol.

[0018] The preparation method of the modified epoxy resin grouting material includes the following steps: Step S1, Preparation of carboxyl-terminated modified epoxy resin: Bisphenol A type epoxy resin and a catalyst aqueous solution of the required mass fraction are added to a reactor containing toluene, and the mixture is heated and stirred at 65–70°C for 2–3 h; a dicarboxylic acid of the required mass fraction is dissolved in an equal volume of isopropanol, mixed, and then added to the reactor, and the mixture is heated and stirred at 65–70°C for 0.5–1.5 h to obtain a prepolymer. After cooling to room temperature, the prepolymer is allowed to stand in methanol to separate into layers, the solvent is removed, and then it is vacuum dried to constant weight to obtain the carboxyl-terminated modified epoxy resin. Step S2, Preparation of modified polyamide: Add the required mass fraction of adipic acid and triethylenetetramine to a reaction vessel equipped with a stirring device and a condenser. Gradually raise the temperature to 180°C and stir at a constant speed for 1 hour. React at a constant temperature for 2 hours. When no distilled water is produced, slowly lower the temperature to 50-60°C. Continue stirring and maintain the temperature at a constant temperature for 1 hour. Finally, stop heating and cool to room temperature to obtain low-viscosity polyamide. Step S3, prepare epoxy resin grouting material component A (epoxy resin part): mix the required mass parts of reactive diluent, coupling agent, toughening agent and surfactant with the carboxyl-terminated modified epoxy resin prepared in step S1 to obtain epoxy resin grouting material component A, and seal and store it. Step S4, prepare epoxy resin grouting material component B (curing agent part): mix the required mass fraction of alicyclic amine, curing agent accelerator and modified polyamide prepared in step S2 with the mixture until uniform, and then seal and store the epoxy resin grouting material component B.

[0019] Preferably, when used, the mass fraction ratio of component A to component B of the epoxy resin grouting material is 2:1 to 3:1.

[0020] The beneficial effects of applying this invention are as follows: (1) The epoxy resin grouting material described in this invention uses carboxyl-terminated modified epoxy resin, which introduces strongly hydrophilic carboxyl groups and hydroxyl groups generated during the modification process into the epoxy resin molecular chain, greatly enhancing the affinity of the epoxy resin grouting material for water molecules, allowing the hydrophilic groups of the modified epoxy molecules to extend into the water cover layer in the cracks of the building body, overcoming the drawback of existing grouting materials not being compatible with the water cover layer.

[0021] (2) The use of hydrophilic reactive diluents further enhances the hydrophilicity of epoxy resin grouting materials. Excessive hydrophilic diluent molecules will selectively transfer to the damp interface of the cement matrix, replace water molecules, improve the repair of damp cracks in the matrix, and form good wetting of the water-covered layer.

[0022] (3) Epoxy resin active toughening agent is a type of polyether compound containing multiple hydroxyl groups in a long-chain linear molecular structure. The hydroxyl groups can react with epoxy resin and curing agent, which can increase the proportion of flexible network in the cross-linked structure and improve the flexibility and internal stress of epoxy cured product. The addition of active toughening agent can not only reduce the viscosity of the formulation system, but the introduction of polyhydroxy polyether compound can also enhance the hydrophilicity of epoxy resin grouting material and the bonding strength with concrete substrate.

[0023] (4) The surfactant contains defoaming polysiloxane, which can make the particles evenly dispersed in the mixture and has a good dispersing effect; the addition of silane coupling agent also improves the performance and bonding strength of epoxy resin grouting material.

[0024] (5) Low viscosity modified polyamide, as a modified polyamine, has the advantages of low viscosity, simple formulation operation, non-toxicity, non-polluting environment, and rapid curing at room temperature. In order to improve the performance of epoxy cured products by improving the defects of amine curing agents, the addition of low viscosity alicyclic amine can reduce the viscosity of epoxy resin grouting material system, making the epoxy resin cured product have a longer trial period, better weather resistance, and higher mechanical strength. Curing accelerator can improve the room temperature and low temperature curing rate of epoxy resin, while improving the mechanical properties of cured products and being more environmentally friendly.

[0025] The epoxy resin grouting material prepared by this invention can effectively change the surface structure of the water-covered layer at the interface of concrete cracks when repairing concrete cracks in humid environments. This increases the wetting performance of the epoxy resin grouting material on the water-covered concrete substrate, overcoming the drawback of existing grouting materials being incompatible with water. Low-viscosity modified polyamide and alicyclic amine, acting as curing agents, effectively reduce the viscosity of the formulation system and increase the penetration radius of the epoxy resin grouting material. The introduction of polyhydroxy polyether compounds and hydrophilic reactive diluents enhances the bonding strength between the epoxy resin grouting material and the concrete substrate, while reducing the volume shrinkage rate after curing. This allows water molecules to exist in the cured epoxy resin grouting material system in the form of bound water, eliminating the problems of insufficient strength and durability caused by water evaporation defects after curing in existing grouting materials. This invention achieves excellent grouting bonding at the interface of concrete cracks in humid environments, and also features low viscosity, high strength, high toughness, and high adhesion.

[0026] Example 1 An embodiment of the low-viscosity, high-strength modified epoxy resin grouting material of the present invention includes the following raw material components in parts by weight: (1) 90 parts by weight of carboxyl-terminated modified epoxy resin, 30 parts by weight of reactive diluent (specifically polypropylene glycol diglycidyl ether, with a viscosity of 10-20 mPa.s at 25°C), 8 parts by weight of silane coupling agent (specifically γ-aminopropyltrimethoxysilane), 6 parts by weight of reactive toughening agent (specifically liquid nitrile rubber) and 3 parts by weight of surfactant (specifically fatty alcohol polyoxyethylene ether) were stirred at 500 r / min for 15 min under a dry inert gas protective atmosphere, and then sealed and packaged according to specifications to obtain component A. (2) 40 parts by weight of modified polyamide, 40 parts by weight of alicyclic amine (specifically isophorone diamine) and 10 parts by weight of curing accelerator (specifically 2,4,6-tris(dimethylaminomethyl)phenol) were stirred at 300 r / min for 30 min under a dry inert gas protective atmosphere, and then sealed and packaged according to specifications to obtain component B. Components A and B are prepared and stored separately. When using them, they are mixed at a weight ratio of 2:1. Example

[0027] An embodiment of the low-viscosity, high-strength modified epoxy resin grouting material of the present invention includes the following steps: (1) 85 parts by weight of carboxyl-terminated modified epoxy resin, 25 parts by weight of reactive diluent (specifically polypropylene glycol diglycidyl ether, with a viscosity of 10-20 mPa.s at 25°C), 6 parts by weight of silane coupling agent (specifically γ-aminopropyltrimethoxysilane), 5 parts by weight of reactive toughening agent (specifically liquid nitrile rubber) and 2 parts by weight of surfactant (specifically fatty alcohol polyoxyethylene ether) were stirred at 500 r / min for 15 min under a dry inert gas protective atmosphere, and then sealed and packaged according to specifications to obtain component A; (2) 45 parts by weight of modified polyamide, 45 parts by weight of alicyclic amine (specifically isophorone diamine) and 5 parts by weight of curing accelerator (specifically 2,4,6-tris(dimethylaminomethyl)phenol) were stirred at 300 r / min for 30 min under a dry inert gas protective atmosphere, and then sealed and packaged according to specifications to obtain component B. Components A and B are prepared and stored separately. When using them, they are mixed at a weight ratio of 2.5:1. Example

[0028] An embodiment of the low-viscosity, high-strength modified epoxy resin grouting material of the present invention includes the following steps: (1) 80 parts by weight of carboxyl-terminated modified epoxy resin, 20 parts by weight of reactive diluent (specifically polypropylene glycol diglycidyl ether, with a viscosity of 10-20 mPa.s at 25°C), 4 parts by weight of silane coupling agent (specifically γ-aminopropyltrimethoxysilane), 4 parts by weight of reactive toughening agent (specifically liquid nitrile rubber) and 1 part by weight of surfactant (specifically fatty alcohol polyoxyethylene ether) were stirred at 500 r / min for 15 min under a dry inert gas protective atmosphere, and then sealed and packaged according to specifications to obtain component A. (2) 50 parts by weight of modified polyamide, 50 parts by weight of alicyclic amine (specifically isophorone diamine) and 1 part by weight of curing accelerator (specifically 2,4,6-tris(dimethylaminomethyl)phenol) were stirred at 300 r / min for 30 min under a dry inert gas protective atmosphere, and then sealed and packaged according to specifications to obtain component B. Components A and B are prepared and stored separately. When using them, they are mixed at a weight ratio of 3:1.

[0029] Performance testing: The mechanical properties of the low-viscosity, high-strength modified epoxy resin grouting material prepared in Examples 1 to 3 of this invention were tested.

[0030] Compressive strength: The compressive strength of the specimens was determined according to GB / T 2569-1995 "Compression test method for resin castings".

[0031] Tensile shear strength: The tensile shear strength was determined in accordance with GB 7124-2008 "Determination of tensile shear strength of adhesives (rigid materials and rigid materials)".

[0032] Tensile strength: The tensile strength of the specimen was determined according to GB / T 2568-1995 "Compression Test Method for Resin Castings". Bond strength: The bond strength of the figure-eight cement mortar blocks was determined according to GB / T 16777-1997 "Test Methods for Waterproof Coatings for Buildings".

[0033] Permeability resistance and permeability ratio: The permeability resistance of cement mortar specimens was determined according to GB 18445-2001 "Cement-based penetrating crystalline waterproof materials".

[0034] Mechanical properties of low viscosity, high strength modified epoxy resin grouting materials As can be seen, increasing the proportion of low-viscosity polyamide curing agent significantly improves the compressive strength, shear strength, and adhesive strength of epoxy resin grouting materials. Furthermore, components A and B are packaged separately and mixed uniformly according to the specified ratio before use, allowing for flexible formulation design based on different application scenarios. The low-viscosity, high-strength modified epoxy resin grouting materials prepared in Examples 1-3 mainly exhibit high compressive strength, high tensile strength, high elongation at break, and high adhesive strength. Example 2, in particular, demonstrates overall performance superior to similar advanced products.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A modified epoxy resin grouting material, characterized in that, The sealant comprises component A and component B. By weight, component A comprises the following raw materials: 70-100 parts of carboxyl-terminated modified epoxy resin 20-30 parts of reactive diluent 5-8 parts of coupling agent 2-6 parts toughening agent 1-3 parts surfactant; Component B comprises the following raw materials: 45-50 parts of modified polyamide 45-50 parts of alicyclic amine Curing accelerator 1 to 10 parts.

2. The modified epoxy resin grouting material according to claim 1, characterized in that, The carboxyl-terminated modified epoxy resin of component A is an anionic hydrophilic epoxy resin modified with dicarboxylic acid, and its epoxy value is 0.40 to 0.

47. In some embodiments, the raw material components used in the modification of the carboxyl-terminated modified epoxy resin include dicarboxylic acid, bisphenol A type epoxy resin and catalyst, and the mass fraction ratio of the dicarboxylic acid, bisphenol A type epoxy resin and catalyst is 0.8:1:0.

05.

3. The modified epoxy resin grouting material according to claim 1, characterized in that, The dicarboxylic acid includes at least one of oxalic acid, malonic acid, succinic acid, glutaric acid, azelaic acid, isophthalic acid, phthalic acid, terephthalic acid, and dimethyl terephthalate; preferably oxalic acid or azelaic acid; The bisphenol A epoxy resin is of at least one of E-32, E42, E44, E51 and E55; preferably E44 or E51; the catalyst is of at least one of benzyltriethylammonium chloride, tetrabutylammonium bromide and 1-butyl-3-methylimidazolium bromide; preferably benzyltriethylammonium chloride; The active diluent of component A is an aliphatic polyepoxy glycidyl ether; it includes at least one of alkyl glycidyl ether, butyl glycidyl ether, benzyl glycidyl ether, polypropylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, glycerol triglycidyl ether, and butylene glycol diglycidyl ether; preferably benzyl glycidyl ether or polypropylene glycol diglycidyl ether. The coupling agent of component A is a silane coupling agent containing an epoxy group or an amino functional group in its molecule, including at least one of γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 3-glycidyl etheroxypropyltrimethoxysilane, 3-glycidyl etheroxypropyltriethoxysilane and N,N-diethyl-3-aminopropyltrimethoxysilane; preferably γ-aminopropyltrimethoxysilane.

4. The modified epoxy resin grouting material according to claim 1, characterized in that, The toughening agent in component A is an active toughening agent, which includes at least one of liquid polysulfide rubber, liquid nitrile rubber, liquid chloroprene rubber, and liquid polyether; preferably liquid nitrile rubber.

5. The modified epoxy resin grouting material according to claim 1, characterized in that, The surfactant in component A is a low-foaming, high-penetration nonionic surfactant, which includes at least one of fatty alcohol polyoxyethylene ether, alkylphenol polyoxyethylene ether, fatty acid polyoxyethylene ester, polyoxyethylene alkylamine, and polyoxyethylene alkylamide; preferably fatty alcohol polyoxyethylene ether. The modified polyamide of component B is a diacid-modified low-viscosity polyamide with an amine value of 300-350 mgKOH / g; in some embodiments, the raw material components used in the modification of the low-viscosity polyamide include diacid and polyamine, and the mass fraction ratio of the diacid to the polyamine is 1:

2. The dicarboxylic acid includes at least one of oxalic acid, malonic acid, succinic acid, glutaric acid, azelaic acid, adipic acid, isophthalic acid, phthalic acid, terephthalic acid, and benzoic acid; preferably adipic acid.

6. The modified epoxy resin grouting material according to claim 1, characterized in that, The curing agent raw material is a polyamine, including at least one of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diallyltriamine, and triethylenediamine; preferably diethylenetriamine or triethylenetetramine.

7. The modified epoxy resin grouting material according to claim 1, characterized in that, The alicyclic amines in component B include 1,3-cyclohexanedimethylamine, 4,4-cyclohexanedimethylamine, and cyclohexanediamine. ， -At least one of diaminodicyclohexylmethane, cyclohexyldimethylamine and isophorone diamine; preferably 1,3-cyclohexyldimethylamine or isophorone diamine.

8. The modified epoxy resin grouting material according to claim 1, characterized in that, The curing accelerator of component B includes at least one of diethanolamine, triethanolamine, triethylamine, m-phenylenediamine, diaminephenylmethane, and 2,4,6-tris(dimethylaminomethyl)phenol; preferably triethanolamine or 2,4,6-tris(dimethylaminomethyl)phenol.

9. The preparation method of the modified epoxy resin grouting material according to claim 1, comprising the following steps: Step S1, Preparation of carboxyl-terminated modified epoxy resin: Bisphenol A type epoxy resin and a catalyst aqueous solution of the required mass fraction are added to a reactor containing toluene, and the mixture is heated and stirred at 65–70°C for 2–3 h; a dicarboxylic acid of the required mass fraction is dissolved in an equal volume of isopropanol, mixed, and then added to the reactor, and the mixture is heated and stirred at 65–70°C for 0.5–1.5 h to obtain a prepolymer. After cooling to room temperature, the prepolymer is allowed to stand in methanol to separate into layers, the solvent is removed, and then it is vacuum dried to constant weight to obtain the carboxyl-terminated modified epoxy resin. Step S2, Preparation of modified polyamide: Add the required mass fraction of adipic acid and triethylenetetramine to a reaction vessel equipped with a stirring device and a condenser. Gradually raise the temperature to 180°C and stir at a constant speed for 1 hour. React at a constant temperature for 2 hours. When no distilled water is produced, slowly lower the temperature to 50-60°C. Continue stirring and maintain the temperature at a constant temperature for 1 hour. Finally, stop heating and cool to room temperature to obtain low-viscosity polyamide. Step S3, prepare epoxy resin grouting material component A (epoxy resin part): mix the required mass parts of reactive diluent, coupling agent, toughening agent and surfactant with the carboxyl-terminated modified epoxy resin prepared in step S1 to obtain epoxy resin grouting material component A, and seal and store it. Step S4, prepare epoxy resin grouting material component B (curing agent part): mix the required mass fraction of alicyclic amine, curing agent accelerator and modified polyamide prepared in step S2 with the mixture until uniform, and then seal and store the epoxy resin grouting material component B.