A deep-penetrating epoxy reinforcement material for concrete and its preparation method

Abstract

This invention relates to the field of building materials technology, specifically to a deep-penetrating epoxy reinforcement material for concrete and its preparation method, comprising component A and component B in a mass ratio of 3:1 to 5:1; component A is prepared from the following raw materials in parts by mass: 45 to 60 parts of bisphenol F type epoxy resin, 10 to 20 parts of C12 to C14 alkyl glycidyl ether, 5 to 12 parts of 1,6-hexanediol diglycidyl ether, 3 to 8 parts of nano-silica and silane coupling agent hybrid modifier, 0.5 to 2.5 parts of polyether modified polydimethylsiloxane, 1 to 4 parts of γ-glycidyl etheroxypropyltrimethoxysilane, and benzyl glycidyl ether to make up to 100 parts. This invention utilizes a synergistic viscosity-reducing system of bisphenol F epoxy resin and composite reactive diluent to reduce the initial viscosity of the mixture of components A and B to below 20 mPa·s, while achieving a compressive strength of over 85 MPa and a tensile strength of over 35 MPa in the cured product, thus achieving a balance between ultra-low viscosity and high strength.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a deep-penetrating epoxy reinforcement material for concrete and its preparation method. Background Technology

[0002] During long-term service, concrete structures are affected by factors such as loads, environmental erosion, and material aging, resulting in the formation of microcracks and capillary pores, leading to decreased strength and deterioration of durability. Penetrating epoxy reinforcement materials enter the concrete through the capillary action of a low-viscosity liquid, forming a cross-linked network after curing, which can effectively improve the overall strength and density of the concrete.

[0003] Existing patent CN113149516B discloses a low-viscosity, high-penetration epoxy waterproofing material for reinforcing and sealing concrete in buildings. It uses a compound of bisphenol A type epoxy resin and 1,4-butanediol diglycidyl ether, combined with a modified cycloaliphatic amine and polyetheramine composite curing agent, to achieve penetration and reinforcement of microcracks in concrete.

[0004] However, this patent uses bisphenol A type epoxy resin as the matrix, which has a high inherent viscosity. A large amount of diluent needs to be added to reduce the viscosity of the system, resulting in a decrease in the crosslinking density of the cured product and damage to its mechanical strength. At the same time, this patent does not involve the control of surface tension, so the material has limited wetting and spreading ability in the micro-capillaries of concrete, and the penetration depth is difficult to meet the requirements of deep reinforcement. In addition, the epoxy system of this patent relies only on physical adhesion to concrete and lacks chemical bonding. The strength of the interfacial transition zone is low, and the adhesion weakens significantly in humid environments.

[0005] Existing patent CN102504670A discloses a penetrating epoxy resin waterproof coating for concrete, which uses furfural and acetone as active reaction diluents. Although this can significantly reduce viscosity, furfural and acetone are volatile organic compounds. During the curing process, they escape, resulting in a large shrinkage rate and high porosity of the cured product, which is seriously insufficient in mechanical strength. Moreover, it is harmful to the health of construction workers and does not meet the requirements of green environmental protection.

[0006] Currently, deep penetration reinforcement of concrete faces the following technical bottlenecks: The contradiction between viscosity and strength: although adding a large amount of reactive diluent can reduce viscosity, it will significantly reduce the crosslinking density and mechanical strength of the cured product. The disconnect between penetration and wetting means that low viscosity does not equal high penetration. If the surface tension of the material is too high, it cannot wet and spread in the micro-capillary pores, thus limiting the penetration depth. The weak bonding between the interface and the matrix means that conventional epoxy systems rely solely on physical adhesion to concrete, lacking chemical bonding, resulting in low strength and poor durability in the interface transition zone. The difference between dry and wet conditions is that conventional epoxy systems have extremely poor adhesion to wet substrates, while reinforcement scenarios such as water conservancy projects and underground structures are often in wet or water-containing environments.

[0007] Therefore, the engineering community urgently needs a concrete deep-penetrating epoxy reinforcement material that combines ultra-low viscosity deep penetration, low surface tension wetting and spreading, high-strength interface anchoring, and high-strength bonding to damp substrates. Summary of the Invention

[0008] The primary objective of this invention is to provide a deep-penetrating epoxy reinforcement material for concrete and its preparation method.

[0009] A further objective of this invention is to provide a concrete deep-penetrating epoxy reinforcement material, which is composed of component A and component B in a mass ratio of 3:1 to 5:1. Component A is prepared from the following raw materials in parts by weight: 45 to 60 parts of bisphenol F type epoxy resin, 10 to 20 parts of C12 to C14 alkyl glycidyl ether, 5 to 12 parts of 1,6-hexanediol diglycidyl ether, 3 to 8 parts of nano silica and silane coupling agent hybrid modifier, 0.5 to 2.5 parts of polyether modified polydimethylsiloxane, 1 to 4 parts of γ-glycidyl etheroxypropyltrimethoxysilane, and benzyl glycidyl ether to make up to 100 parts; Component B is prepared from the following raw materials in parts by weight: 25 to 40 parts of polyetheramine with a number average molecular weight of 230, 30 to 45 parts of isophorone diamine, 8 to 18 parts of phenolic amine curing agent, 8 to 15 parts of benzyl alcohol, and 1 to 4 parts of 2,4,6-tris(dimethylamino)methylphenol. The preparation method of the nano-silica and silane coupling agent hybrid modifier is as follows: nano-silica is dispersed in ethanol, and γ-glycidoxypropyltrimethoxysilane is added. The mass ratio of nano-silica to γ-glycidoxypropyltrimethoxysilane is 1:1.5 to 1:2.5. The mixture is stirred and reacted at 55 to 65°C for 3 to 5 hours. Then, the ethanol is removed by vacuum rotary evaporation at 50°C, and the mixture is dried at 80°C for 4 hours. Finally, it is ground through a 200-mesh sieve to obtain the final product. The polyether-modified polydimethylsiloxane is a polyether segment-modified polydimethylsiloxane copolymer.

[0010] Preferably, the mass ratio of component A to component B is 4 to 1.

[0011] Preferably, the bisphenol F type epoxy resin has an epoxy equivalent of 165 to 175 g / mol and a viscosity of 3000 to 5000 mPa·s at 25°C.

[0012] Preferably, the C12 to C14 alkyl glycidyl ether has a viscosity of 5 to 10 mPa·s at 25°C; the 1,6-hexanediol diglycidyl ether has an epoxy equivalent of 130 to 150 g / mol and a viscosity of 15 to 25 mPa·s at 25°C.

[0013] Preferably, the nano-silica has a particle size of 15 to 25 nm and a specific surface area of ​​180 to 220 m². 2 / g; the phenolic amine curing agent is a Mannich base modified amine curing agent with an amine value of 460 to 480 mg KOH / g.

[0014] A method for preparing the aforementioned deep-penetrating epoxy reinforcement material for concrete includes the following steps: Preparation of nano-silica and silane coupling agent hybrid modifier: Nano-silica is dispersed in 95% ethanol by volume, γ-glycidoxypropyltrimethoxysilane is added, and the mixture is stirred and reacted at 55 to 65°C under nitrogen protection for 3 to 5 hours. Then, the ethanol is removed by vacuum rotary evaporation at 50°C, and the mixture is dried at 80°C for 4 hours. The mixture is then ground through a 200-mesh sieve to obtain the nano-silica and silane coupling agent hybrid modifier. Preparation of Component A: Bisphenol F type epoxy resin, C12 to C14 alkyl glycidyl ether, 1,6-hexanediol diglycidyl ether and benzyl glycidyl ether were stirred at 300 r / min for 15 min. Nano-silica and silane coupling agent hybrid modifier were added and stirred at 500 r / min for 30 min, followed by ultrasonic dispersion for 20 min. γ-glycidyl etheroxypropyltrimethoxysilane was added and stirred at 300 r / min for 10 min. Finally, polyether-modified polydimethylsiloxane was added and stirred at 200 r / min for 10 min. The mixture was then degassed under a vacuum of 0.08 MPa for 15 min to obtain Component A. Preparation of Component B: Polyetheramine, isophorone diamine and phenolic amine curing agent were stirred at 200 r / min for 15 min, benzyl alcohol was added and stirred at 200 r / min for 10 min, and finally 2,4,6-tris(2,4,6)-dimethylaminomethylphenol was added and stirred at 300 r / min for 5 min to obtain Component B.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention utilizes a synergistic viscosity-reducing system of bisphenol F epoxy resin and composite reactive diluent to reduce the initial viscosity of the mixture of components A and B to below 20 mPa·s, while achieving a compressive strength of over 85 MPa and a tensile strength of over 35 MPa in the cured product, thus achieving a balance between ultra-low viscosity and high strength.

[0016] 2. This invention introduces polyether-modified polydimethylsiloxane, which reduces the surface tension of the material to below 28 mN / m, reduces the contact angle with concrete to below 10°, and achieves a penetration depth of over 60 mm, which is significantly superior to conventional epoxy reinforcement materials.

[0017] 3. This invention uses a hybrid modifier of nano-silica and silane coupling agent, which undergoes in-situ hydrolysis and condensation in the alkaline environment of concrete to form Si-O-Si chemical bonds, anchoring the epoxy network to the concrete pore wall. The interfacial bonding strength is increased by more than 30% compared with the physical adhesion system.

[0018] 4. The present invention adopts a three-gradient curing system, which achieves a tensile bond strength of more than 3.5 MPa on a damp concrete substrate with a moisture content of 8%, and the failure mode is cohesive failure of concrete, thus realizing the synergy of deep penetration and high-strength bonding on a damp substrate. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The concrete deep-penetrating epoxy reinforcement material of the present invention achieves its purpose through the following synergistic mechanism.

[0021] (1) Synergistic viscosity reduction mechanism of bisphenol F epoxy resin and composite reactive diluent: The connecting group between the two benzene rings in the molecular structure of bisphenol F epoxy resin is methylene, which does not have the steric hindrance of methyl in bisphenol A epoxy resin. The molecular chain is more compact, and the inherent viscosity is only one-third to one-half of that of bisphenol A epoxy resin, which reduces the viscosity of the matrix from the source.

[0022] C12 to C14 alkyl glycidyl ethers contain long-chain alkyl groups with large steric hindrance, which can effectively weaken the polar interactions between epoxy resin molecules and achieve efficient viscosity reduction; 1,6-hexanediol diglycidyl ether contains flexible hexamethylene segments, which not only have a viscosity-reducing effect, but also provide bifunctional crosslinking points, maintaining the crosslinking density and mechanical strength of the cured product while reducing viscosity.

[0023] The three components work together to achieve ultra-low viscosity while avoiding the increased brittleness and significant decrease in strength of the cured product caused by a single diluent.

[0024] (2) Surface tension regulation and wetting promotion mechanism of polyether-modified polydimethylsiloxane: Polyether-modified polydimethylsiloxane is a special surfactant that combines the low surface tension of organosilicon with the hydrophilicity of polyether. Its siloxane segments can significantly reduce the surface tension of the material, making it lower than the critical surface tension of concrete, thereby enabling spontaneous wetting and spreading in the micro-capillary pores; the polyether segments provide compatibility with epoxy resin, avoiding oil seepage and migration. This penetration promoter significantly reduces the contact angle of the material in the capillary pores of concrete. According to the Laplace equation, capillary penetration force is proportional to the product of surface tension and the cosine of the contact angle. The reduction of the contact angle greatly increases the capillary penetration force and the penetration depth increases exponentially.

[0025] (3) Interface anchoring enhancement mechanism of nano silica and silane coupling agent hybrid modifier: In this invention, nano silica and γ-glycidyl etheroxypropyltrimethoxysilane are pre-hybridized to make the silane coupling agent covalently grafted onto the surface of nano silica to form organic and inorganic hybrid nanoparticles.

[0026] After the hybrid modifier penetrates into the capillary pores of the concrete along with the epoxy resin, it encounters the alkaline environment of the concrete. The unreacted methoxy groups in the silane coupling agent undergo hydrolysis to generate silanol groups. These silanol groups undergo a condensation reaction with the hydroxyl groups on the surface of the concrete hydration products to form Si-O-Si chemical bonds, anchoring the epoxy resin network to the pore walls of the concrete.

[0027] This interface anchoring mechanism upgrades traditional physical adhesion to chemical bonding, significantly improving the strength of the interface transition zone.

[0028] Meanwhile, nano-silica acts as a nano-reinforcing agent in the epoxy network, hindering crack propagation and improving the mechanical strength and durability of the cured product.

[0029] Compared with conventional unmodified nano-silica, the epoxy groups on the surface of the hybrid modifier participate in the curing and cross-linking reaction, chemically bonding the nano-silica to the epoxy network, effectively preventing the aggregation and sedimentation of nanoparticles in low viscosity systems.

[0030] (4) The three-gradient curing mechanism of polyetheramine, isophorone diamine, and phenolic amine: Polyetheramine D-230 contains flexible polyether segments with moderate reactivity, providing a slow curing rate in the early stage of mixing, thus providing sufficient working time for deep penetration of the material; isophorone diamine contains a rigid alicyclic structure, providing secondary crosslinking after the initial curing of polyetheramine, giving the cured product high strength and heat resistance; phenolic amine contains phenolic hydroxyl and amino groups, which can cure rapidly under humid conditions and provide interfacial adhesion. The three form a progressive curing in a time gradient: first penetration, then anchoring, and then reinforcement, achieving the unity of deep penetration and high-strength consolidation.

[0031] Raw material source: Bisphenol F type epoxy resin: grade CYDF-170, epoxy equivalent 165 to 175 g / mol, viscosity at 25℃ 3000 to 5000 mPa·s, industrial grade, Yueyang Changsheng Industry and Trade Co., Ltd. C12 to C14 alkyl glycidyl ethers: viscosity 5 to 10 mPa·s at 25℃, industrial grade, Anhui Xinyuan Technology Co., Ltd. 1,6-Hexanediol diglycidyl ether: epoxy equivalent 130 to 150 g / mol, viscosity at 25°C 15 to 25 mPa·s, industrial grade, Anhui Xinyuan Technology Co., Ltd. Benzyl glycidyl ether: Industrial grade, Anhui Xinyuan Technology Co., Ltd.; Nano-silica: Particle size 15 to 25 nm, specific surface area 180 to 220 m² 2 / g, industrial grade, Wacker Chemie; γ-glycidyl etheroxypropyltrimethoxysilane: Grade KH-560, industrial grade, Nanjing Shuguang Silane Chemical Co., Ltd.; Polyether-modified polydimethylsiloxane: Brand BYK-307, industrial grade, BYK Chemicals; Polyetheramine D-230: Number average molecular weight 230, viscosity at 25°C approximately 35 mPa·s, industrial grade, Huntsman Chemicals; Isophorone diamine: viscosity at 25°C approximately 18 mPa·s, industrial grade, Evonik Degussa; Phenolic amine curing agent: Brand T-31, amine value 460 to 480 mgKOH / g, industrial grade, Changzhou Tiansheng Chemical Co., Ltd.; Benzyl alcohol: analytical grade, Sinopharm Chemical Reagent Co., Ltd.; 2,4,6-Tris(2,4,6)-Dimethylaminomethylphenol: Analytical grade, Sinopharm Chemical Reagent Co., Ltd.; Ethanol: 95% by volume, industrial grade, Sinopharm Chemical Reagent Co., Ltd.

[0032] Example 1: Preparation of nano-silica and silane coupling agent hybrid modifier: Nano-silica with a particle size of 15 to 25 nm was dispersed in 95% ethanol by volume, and KH-560 silane coupling agent was added. The mass ratio of nano-silica to KH-560 was 1:2. The mixture was stirred and reacted at 60°C under nitrogen protection for 4 hours. Then, the ethanol was removed by vacuum rotary evaporation at 50°C, and the mixture was dried at 80°C for 4 hours. The mixture was then ground through a 200-mesh sieve to obtain the nano-silica and silane coupling agent hybrid modifier.

[0033] Component A raw material formula: The composition includes 52 parts of bisphenol F type epoxy resin, 16 parts of C12 to C14 alkyl glycidyl ether, 9 parts of 1,6-hexanediol diglycidyl ether, 5 parts of nano silica and silane coupling agent hybrid modifier, 1.5 parts of polyether modified polydimethylsiloxane BYK-307, 2.5 parts of KH-560 silane coupling agent, and 14 parts of benzyl glycidyl ether.

[0034] Preparation process of component A: Bisphenol F type epoxy resin, C12 to C14 alkyl glycidyl ether, 1,6-hexanediol diglycidyl ether and benzyl glycidyl ether were stirred at 300 r / min for 15 min. Nano silica and silane coupling agent hybrid modifier were added and stirred at 500 r / min for 30 min, followed by ultrasonic dispersion for 20 min. KH-560 silane coupling agent was added and stirred at 300 r / min for 10 min. Finally, polyether modified polydimethylsiloxane was added and stirred at 200 r / min for 10 min. The mixture was then degassed under a vacuum of 0.08 MPa for 15 min to obtain component A.

[0035] Component B raw material formulation: The composition of the product is as follows: 35 parts of polyetheramine D-230, 38 parts of isophorone diamine, 12 parts of phenolic amine curing agent T-31, 12 parts of benzyl alcohol, and 3 parts of 2,4,6-tris(2,4,6)-dimethylaminomethylphenol.

[0036] Preparation process of component B: Polyetheramine D-230, isophorone diamine, and phenolic amine curing agent T-31 were stirred at 200 r / min for 15 min. Benzyl alcohol was added and stirred at 200 r / min for 10 min. Finally, 2,4,6-tris(dimethylamino)methylphenol was added and stirred at 300 r / min for 5 min to obtain component B.

[0037] In this embodiment, component A and component B are mixed in a mass ratio of 4:1.

[0038] Example 2: Preparation of the nano-silica and silane coupling agent hybrid modifier: same as in Example 1.

[0039] Component A raw material formula: The composition includes 45 parts of bisphenol F type epoxy resin, 20 parts of C12 to C14 alkyl glycidyl ether, 12 parts of 1,6-hexanediol diglycidyl ether, 3 parts of nano silica and silane coupling agent hybrid modifier, 2.5 parts of polyether modified polydimethylsiloxane BYK-307, 4 parts of KH-560 silane coupling agent, and 13.5 parts of benzyl glycidyl ether.

[0040] Preparation process of component A: Same as in Example 1.

[0041] Component B raw material formulation: The composition is as follows: 40 parts of polyetheramine D-230, 32 parts of isophorone diamine, 10 parts of phenolic amine curing agent T-31, 14 parts of benzyl alcohol, and 4 parts of 2,4,6-tris(dimethylamino)methylphenol.

[0042] Preparation process of component B: Same as in Example 1.

[0043] In this embodiment, component A and component B are mixed in a mass ratio of 3:1.

[0044] Example 3: Preparation of the nano-silica and silane coupling agent hybrid modifier: same as in Example 1.

[0045] Component A raw material formula: The composition includes 60 parts of bisphenol F type epoxy resin, 10 parts of C12 to C14 alkyl glycidyl ether, 5 parts of 1,6-hexanediol diglycidyl ether, 8 parts of nano silica and silane coupling agent hybrid modifier, 0.5 parts of polyether modified polydimethylsiloxane BYK-307, 1 part of KH-560 silane coupling agent, and 15.5 parts of benzyl glycidyl ether.

[0046] Preparation process of component A: Same as in Example 1.

[0047] Component B raw material formulation: The composition includes 25 parts of polyetheramine D-230, 45 parts of isophorone diamine, 18 parts of phenolic amine curing agent T-31, 8 parts of benzyl alcohol, and 4 parts of 2,4,6-tris(2,4,6)-aminophenol.

[0048] Preparation process of component B: Same as in Example 1.

[0049] In this embodiment, component A and component B are mixed at a mass ratio of 5:1.

[0050] Comparative Example 1: The blank comparative example lacks the key components of this invention.

[0051] Component A raw material formula: The composition consists of 70 parts of bisphenol A type epoxy resin E-51, 28 parts of benzyl glycidyl ether, and 2 parts of KH-560 silane coupling agent.

[0052] Preparation process of component A: Bisphenol A type epoxy resin E-51 and benzyl glycidyl ether were stirred at 300 r / min for 15 min, and KH-560 silane coupling agent was added and stirred at 300 r / min for 10 min to obtain component A.

[0053] Component B raw material formulation: The modified fatty amine curing agent 593 consists of 65 parts, benzyl alcohol 30 parts, and 2,4,6-tris(2,4,6)-dimethylaminomethylphenol 5 parts.

[0054] Preparation process of component B: Modified fatty amine curing agent 593 and benzyl alcohol were stirred at 200 r / min for 10 min, and then 2,4,6-tris(2,4,6)-dimethylaminomethylphenol was added and stirred at 300 r / min for 5 min to obtain component B.

[0055] This comparative example does not contain C12 to C14 alkyl glycidyl ether, 1,6-hexanediol diglycidyl ether, nano silica and silane coupling agent hybrid modifier, polyether modified polydimethylsiloxane, polyether amine, isophorone diamine and phenolic amine. Component A and component B are compounded in a mass ratio of 3:1.

[0056] Comparative Example 2: A comparative example of polyether-modified polydimethylsiloxane is missing.

[0057] Component A raw material formula: 52 parts of bisphenol F type epoxy resin, 16 parts of C12 to C14 alkyl glycidyl ether, 9 parts of 1,6-hexanediol diglycidyl ether, 5 parts of nano silica and silane coupling agent hybrid modifier, 2.5 parts of KH-560 silane coupling agent, and 15.5 parts of benzyl glycidyl ether.

[0058] The preparation process of component A is the same as in Example 1, but without polyether-modified polydimethylsiloxane.

[0059] The raw material formulation for component B is the same as in Example 1.

[0060] Preparation process of component B: Same as in Example 1.

[0061] This comparative example does not contain polyether-modified polydimethylsiloxane. Component A and component B are compounded at a mass ratio of 4:1.

[0062] Comparative Example 3: A comparative example of a hybrid modifier combining nano-silica and silane coupling agent is missing.

[0063] Component A raw material formula: The composition includes 52 parts of bisphenol F type epoxy resin, 16 parts of C12 to C14 alkyl glycidyl ether, 9 parts of 1,6-hexanediol diglycidyl ether, 1.5 parts of polyether-modified polydimethylsiloxane BYK-307, 2.5 parts of KH-560 silane coupling agent, and 19 parts of benzyl glycidyl ether.

[0064] The preparation process of component A is the same as in Example 1, but without the hybrid modifier of nano-silica and silane coupling agent.

[0065] The raw material formulation for component B is the same as in Example 1.

[0066] Preparation process of component B: Same as in Example 1.

[0067] This comparative example does not contain nano-silica or silane coupling agent hybrid modifiers. Component A and component B are compounded at a mass ratio of 4:1.

[0068] Comparative Example 4: The existing technology comparison example represents a scheme using a compound of bisphenol A type epoxy resin and butylene glycol diglycidyl ether.

[0069] Component A raw material formula: The composition of bisphenol A type epoxy resin E-44 is 48 parts, 1,4-butanediol diglycidyl ether is 25 parts, flexible modifier is 12 parts, KH-560 silane coupling agent is 4 parts, and benzyl alcohol is 11 parts. The flexible modifier is prepared by reacting 1,4-butanediol diglycidyl ether with γ-aminopropyltriethoxysilane at a molar ratio of 4:1 at 55°C for 2 hours.

[0070] Preparation process of component A: Bisphenol A type epoxy resin E-44 and 1,4-butanediol diglycidyl ether were stirred at 300 r / min for 15 min, a flexible modifier was added and stirred at 300 r / min for 10 min, KH-560 silane coupling agent was added and stirred at 300 r / min for 10 min, and benzyl alcohol was added and stirred at 200 r / min for 10 min to obtain component A.

[0071] Component B raw material formulation: The mixture consisted of 24 parts of 1,3-diaminomethylcyclohexane, 38 parts of PACM-modified amine curing agent, 25 parts of polyetheramine D-220, and 13 parts of benzyl alcohol. The PACM-modified amine curing agent was prepared by reacting PACM with epoxy resin E-54 benzyl alcohol solution at a mass ratio of 6.5:1 at 52°C for 2 hours.

[0072] Preparation process of component B: 1,3-Diaminomethylcyclohexane, PACM modified amine curing agent and polyetheramine D-220 were stirred at 200 r / min for 15 min, and benzyl alcohol was added and stirred at 200 r / min for 10 min to obtain component B.

[0073] Component A and component B are mixed at a mass ratio of 3:1.

[0074] Comparative Example 5: The existing technology comparison example represents a scheme using a mixture of furfural and acetone as a diluent.

[0075] Component A raw material formula: The composition of the epoxy resin E-51 (BPA type A) is 35 parts, furfural 30 parts, acetone 20 parts, KH-560 silane coupling agent 3 parts, and benzyl glycidyl ether 12 parts.

[0076] Preparation process of component A: Bisphenol A type epoxy resin E-51 was stirred with furfural and acetone at 300 r / min for 15 min, benzyl glycidyl ether was added and stirred at 200 r / min for 10 min, and KH-560 silane coupling agent was added and stirred at 300 r / min for 10 min to obtain component A.

[0077] Component B raw material formulation: The modified fatty amine curing agent 593 consists of 65 parts, benzyl alcohol 30 parts, and 2,4,6-tris(2,4,6)-dimethylaminomethylphenol 5 parts.

[0078] Preparation process of component B: same as comparative example 1.

[0079] Component A and component B are mixed at a mass ratio of 5:1.

[0080] Comparative Example 6: A comparative example in which bisphenol A type epoxy resin was replaced with bisphenol F type epoxy resin and the hybrid modifier was omitted.

[0081] Component A raw material formula: The composition includes 52 parts of bisphenol A type epoxy resin E-51, 16 parts of C12 to C14 alkyl glycidyl ether, 9 parts of 1,6-hexanediol diglycidyl ether, 1.5 parts of polyether-modified polydimethylsiloxane BYK-307, 2.5 parts of KH-560 silane coupling agent, and 19 parts of benzyl glycidyl ether.

[0082] The preparation process of component A is the same as in Example 1, but without the hybrid modifier of nano-silica and silane coupling agent.

[0083] The raw material formulation for component B is the same as in Example 1.

[0084] Preparation process of component B: Same as in Example 1.

[0085] In this comparative example, bisphenol F type epoxy resin was replaced with bisphenol A type epoxy resin E-51, and the hybrid modifier of nano silica and silane coupling agent was omitted. Component A and component B were compounded at a mass ratio of 4:1.

[0086] Comparative Example 7: The hybrid modifier was replaced with unhybridized nano-silica, and the curing system was only a comparative example of polyetheramine.

[0087] Component A raw material formula: The composition includes 52 parts bisphenol F type epoxy resin, 16 parts C12 to C14 alkyl glycidyl ether, 9 parts 1,6-hexanediol diglycidyl ether, 5 parts unmodified fumed silica, 1.5 parts polyether-modified polydimethylsiloxane BYK-307, 2.5 parts KH-560 silane coupling agent, and 14 parts benzyl glycidyl ether. The unmodified fumed silica has a particle size of 15 to 25 nm and a specific surface area of ​​180 to 220 m². 2 / g, without silane coupling agent surface treatment.

[0088] Preparation process of component A: Same as in Example 1, but the nano-silica and silane coupling agent hybrid modifier are replaced with unmodified fumed silica.

[0089] Component B raw material formulation: The composition is 60 parts of polyetheramine D-230, 35 parts of benzyl alcohol, and 5 parts of 2,4,6-tris(dimethylamino)methylphenol.

[0090] Preparation process of component B: Same as in Example 1.

[0091] In this comparative example, component B uses only polyetheramine D-230 and does not contain isophorone diamine or phenolic amine curing agent. Components A and B are mixed at a mass ratio of 4:1.

[0092] Performance testing and results analysis: (1) Viscosity test: Performed in accordance with GB / T2794-1995. The initial viscosity of the mixture of component A and component B was determined using a rotational viscometer at a test temperature of 25℃.

[0093] (2) Surface tension test: Performed in accordance with GB / T22237-2008. The surface tension of the mixture was measured using a surface tension meter at a test temperature of 25℃.

[0094] (3) Contact angle test: The mixture is dropped onto the polished concrete surface and the contact angle is measured at 5s using a contact angle measuring instrument.

[0095] (4) Working time test: The time from when component A and component B are mixed until the viscosity increases to 3 times the initial viscosity is measured at a test temperature of 25℃.

[0096] (5) Penetration depth test: Prepare C30 concrete test blocks with a water-cement ratio of 0.50, standard curing for 28 days, apply the mixture to the surface, keep it under a pressure of 0.2MPa for 30 minutes, and after curing for 7 days, cut it in the vertical direction and measure the penetration depth.

[0097] (6) Mechanical property test: The compressive strength and tensile strength shall be performed in accordance with the provisions of GB / T2567-2008; the tensile bond strength shall be performed in accordance with the provisions of GB / T16777-2008, and shall be tested on dry substrate and damp substrate with 8% moisture content respectively.

[0098] (7) Concrete reinforcement effect test: C30 concrete cylindrical specimens were prepared, the surface was coated with the mixture and kept under a pressure of 0.2 MPa for 30 min. After curing for 7 days, the splitting tensile strength was tested and compared with untreated concrete. The impermeability was tested by the seepage pressure method and the seepage pressure increase ratio was calculated.

[0099] The test results are shown in Tables 1, 2, and 3 below.

[0100] Table 1. Results of viscosity and surface properties tests:

[0101] Test methods: Viscosity according to GB / T2794-1995, surface tension according to GB / T22237-2008, contact angle using a contact angle measuring instrument, and operable time the time it takes for the viscosity to increase to three times the initial value after mixing. Test temperature 25℃. Each sample group is tested three times, and the average value is taken.

[0102] Results Analysis: The mixtures in Examples 1 to 3 exhibited viscosities ranging from 8.6 to 18.5 mPa·s, surface tensions from 25.2 to 28.3 mN / m, contact angles from 6 to 11°, and workable times from 95 to 155 min, demonstrating excellent synergistic effects of low viscosity and low surface tension. Comparative Example 1, without the addition of the composite viscosity reducer and surface tension modifier, had a viscosity as high as 165 mPa·s, a surface tension of 39.5 mN / m, and a contact angle of 35°, indicating extremely poor permeability. Comparative Example 2, lacking polyether-modified polydimethylsiloxane, had a viscosity comparable to Example 1, but its surface tension increased from 26.8 mN / m to 35.6 mN / m, and its contact angle increased from 8° to 25°, indicating that low viscosity does not equate to high wettability, and surface tension regulation is indispensable. Comparative Example 3, lacking the hybrid modifier of nano-silica and silane coupling agent, had surface tension and contact angle close to those of Example 1, indicating that the hybrid modifier had a relatively small impact on surface properties, its main contribution being enhanced interfacial anchoring. Comparative Example 4 used a system of bisphenol A type epoxy resin and 1,4-butanediol diglycidyl ether, with a viscosity of 32.5 mPa·s, 2.6 times that of Example 1, a surface tension of 34.8 mN / m, and a contact angle of 23°, indicating significantly insufficient permeability. Comparative Example 5, although having an extremely low viscosity of 5.8 mPa·s, still had a relatively high surface tension of 31.5 mN / m, and a workable time of only 45 minutes, resulting in a short application window. Comparative Example 6 replaced the bisphenol F type epoxy resin with bisphenol A type epoxy resin E-51, increasing the viscosity from 12.5 mPa·s to 28.6 mPa·s, an increase of 129%. This demonstrates that the choice of epoxy resin type has a decisive influence on the system viscosity, and the low viscosity characteristic of bisphenol F type epoxy resin cannot be compensated for simply replacing bisphenol A type epoxy resin. Although Comparative Example 7 used bisphenol F type epoxy resin and polyether-modified polydimethylsiloxane, the nano-silica was not hybridized with a silane coupling agent, and its viscosity of 15.2 mPa·s was higher than that of Example 1 (12.5 mPa·s), indicating that the unmodified nano-silica had poor dispersibility in low-viscosity systems. Furthermore, component B only used polyetheramine D-230, and the working time of 168 min was too long, resulting in insufficient curing rate.

[0103] Table 2. Test results of penetration depth and mechanical properties:

[0104] Test methods: Penetration depth was measured using the cutting method; mechanical properties were tested according to GB / T2567-2008; and bond strength was tested according to GB / T16777-2008. The moisture content of the damp substrate was 8%. Each sample was tested 5 times, and the average value was taken.

[0105] Results Analysis: Examples 1 to 3 showed penetration depths of 45 to 78 mm, compressive strengths of 76.8 to 92.6 MPa, and wet bond strengths of 3.5 to 4.2 MPa, achieving a synergistic effect of deep penetration, high strength, and wet bond strength. Comparative Example 1 showed a penetration depth of only 8 mm and a wet bond strength of 1.2 MPa, indicating poor overall performance. Comparative Example 2, lacking polyether-modified polydimethylsiloxane, had a penetration depth of 22 mm, a 64.5% decrease compared to Example 1. This demonstrates the decisive role of surface tension control in penetration depth; even with sufficiently low viscosity, excessively high surface tension prevents the material from wetting and spreading within microcapillaries, severely limiting penetration depth. Comparative Example 3 lacked the hybrid modifier of nano-silica and silane coupling agent. The penetration depth of 58 mm was close to that of Example 1 (62 mm), but the wet bond strength was only 2.6 MPa, a decrease of 31.6% compared to Example 1. This demonstrates the key role of the interface anchoring and strengthening mechanism of the hybrid modifier in bonding to wet substrates. The hybrid modifier undergoes in-situ hydrolysis and condensation in the alkaline environment of concrete to form Si-O-Si chemical bonds, anchoring the epoxy network to the pore walls of the concrete. This chemical bond remains stable even in the presence of moisture.

[0106] Comparative Example 4, using existing technology, achieved a penetration depth of 18 mm and a wet bond strength of 2.8 MPa, both lower than those of the present invention. Comparative Example 5, although possessing a penetration depth of 42 mm, had a compressive strength of only 48.2 MPa, severely insufficient, and a wet bond strength of only 1.5 MPa. Comparative Example 6, while combining polyether-modified polydimethylsiloxane with a composite diluent, replaced bisphenol F epoxy resin with bisphenol A epoxy resin, resulting in increased viscosity and a penetration depth of only 32 mm, a 48.4% decrease compared to Example 1. The compressive strength of 82.3 MPa was similar to Example 1, but the penetration depth differed significantly, indicating that the low viscosity characteristic of bisphenol F epoxy resin cannot be compensated for by simply replacing bisphenol A epoxy resin. Although Comparative Example 7 used bisphenol F type epoxy resin and polyether-modified polydimethylsiloxane, the nano-silica was not modified with a silane coupling agent hybrid, making it prone to agglomeration and sedimentation in the low-viscosity epoxy system. Furthermore, component B only used polyetheramine D-230, resulting in insufficient crosslinking density of the cured product. The compressive strength (62.5 MPa) decreased by 26.7% compared to Example 1, and the wet bond strength (2.8 MPa) decreased by 26.3% compared to Example 1. This indicates that the synergistic effect of the present invention, achieved through the combination of bisphenol F type epoxy resin, nano-silica, a silane coupling agent hybrid modifier, and a three-gradient curing system, is not something that can be achieved through a simple combination of existing technologies, and produces unexpected technical effects.

[0107] Table 3. Test results of concrete reinforcement effect:

[0108] Test methods: Splitting tensile strength shall be performed in accordance with GB / T50081-2019. Permeability pressure rise ratio shall be performed in accordance with DL / T5126-2001.

[0109] The concrete specimens were C30 with a water-cement ratio of 0.50 and a standard curing period of 28 days. Treatment conditions: the surface was coated with the mixture, pressure was maintained at 0.2 MPa for 30 minutes, and testing was conducted 7 days after curing. Each group of samples was tested 5 times, and the average value was taken.

[0110] Results Analysis: The splitting tensile strength of Examples 1 to 3 ranged from 5.18 to 5.45 MPa, representing an increase of 35.6% to 42.7% compared to untreated concrete, with an increase in penetration pressure of 248% to 305%, indicating significant reinforcement effects. Comparative Example 1 had a splitting tensile strength of only 3.95 MPa, an increase of 3.4%, and an increase in penetration pressure of 32%, showing virtually no reinforcement effect. Comparative Example 2 lacked polyether-modified polydimethylsiloxane, resulting in shallow penetration depth and poor reinforcement effect; its splitting tensile strength was 4.68 MPa, a decrease of 12.0% compared to Example 1, and its penetration pressure increase was 125%, a decrease of 56.1% compared to Example 1. Comparative Example 3 lacked a hybrid modifier; its splitting tensile strength was 4.85 MPa, a decrease of 8.8% compared to Example 1, and its penetration pressure increase was 165%, a decrease of 42.1% compared to Example 1, demonstrating the contribution of interfacial anchoring to the overall reinforcement effect of concrete. Comparative Example 6 showed a splitting tensile strength of 4.45 MPa, a decrease of 16.4% compared to Example 1, and a permeation pressure increase of 128%, a decrease of 55.1% compared to Example 1; Comparative Example 7 showed a splitting tensile strength of 4.58 MPa, a decrease of 13.9% compared to Example 1, and a permeation pressure increase of 138%, a decrease of 51.6% compared to Example 1. Neither of the two comparative examples achieved the reinforcement effect of the present invention, further demonstrating the integrity and indivisibility of the four-fold synergistic mechanism of the present invention.

[0111] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A deep-penetrating epoxy reinforcement material for concrete, characterized in that, It is composed of component A and component B in a mass ratio of 3:1 to 5:1; Component A is prepared from the following raw materials in parts by weight: 45 to 60 parts of bisphenol F type epoxy resin, 10 to 20 parts of C12 to C14 alkyl glycidyl ether, 5 to 12 parts of 1,6-hexanediol diglycidyl ether, 3 to 8 parts of nano silica and silane coupling agent hybrid modifier, 0.5 to 2.5 parts of polyether modified polydimethylsiloxane, 1 to 4 parts of γ-glycidyl etheroxypropyltrimethoxysilane, and benzyl glycidyl ether to make up to 100 parts; Component B is prepared from the following raw materials in parts by weight: 25 to 40 parts of polyetheramine with a number average molecular weight of 230, 30 to 45 parts of isophorone diamine, 8 to 18 parts of phenolic amine curing agent, 8 to 15 parts of benzyl alcohol, and 1 to 4 parts of 2,4,6-tris(dimethylamino)methylphenol. The preparation method of the nano-silica and silane coupling agent hybrid modifier is as follows: nano-silica is dispersed in ethanol, and γ-glycidoxypropyltrimethoxysilane is added. The mass ratio of nano-silica to γ-glycidoxypropyltrimethoxysilane is 1:1.5 to 1:2.

5. The mixture is stirred and reacted at 55 to 65°C for 3 to 5 hours. Then, the ethanol is removed by vacuum rotary evaporation at 50°C, and the mixture is dried at 80°C for 4 hours. Finally, it is ground through a 200-mesh sieve to obtain the final product. The polyether-modified polydimethylsiloxane is a polyether segment-modified polydimethylsiloxane copolymer.

2. The concrete deep-penetrating epoxy reinforcement material according to claim 1, characterized in that, The mass ratio of component A to component B is 4:

1.

3. The concrete deep-penetrating epoxy reinforcement material according to claim 1, characterized in that, The bisphenol F type epoxy resin has an epoxy equivalent of 165 to 175 g / mol and a viscosity of 3000 to 5000 mPa·s at 25°C.

4. The concrete deep-penetrating epoxy reinforcement material according to claim 1, characterized in that, The C12 to C14 alkyl glycidyl ether has a viscosity of 5 to 10 mPa·s at 25°C; the 1,6-hexanediol diglycidyl ether has an epoxy equivalent of 130 to 150 g / mol and a viscosity of 15 to 25 mPa·s at 25°C.

5. The concrete deep-penetrating epoxy reinforcement material according to claim 1, characterized in that, The nano-silica has a particle size of 15 to 25 nm and a specific surface area of ​​180 to 220 m². 2 / g; the phenolic amine curing agent is a Mannich base modified amine curing agent with an amine value of 460 to 480 mg KOH / g.

6. A method for preparing a deep-penetrating epoxy reinforcement material for concrete according to any one of claims 1 to 5, characterized in that, Includes the following steps: Preparation of nano-silica and silane coupling agent hybrid modifier: Nano-silica is dispersed in 95% ethanol by volume, γ-glycidoxypropyltrimethoxysilane is added, and the mixture is stirred and reacted at 55 to 65°C under nitrogen protection for 3 to 5 hours. Then, the ethanol is removed by vacuum rotary evaporation at 50°C, and the mixture is dried at 80°C for 4 hours. The mixture is then ground through a 200-mesh sieve to obtain the nano-silica and silane coupling agent hybrid modifier. Preparation of Component A: Bisphenol F type epoxy resin, C12 to C14 alkyl glycidyl ether, 1,6-hexanediol diglycidyl ether and benzyl glycidyl ether were stirred at 300 r / min for 15 min. Nano-silica and silane coupling agent hybrid modifier were added and stirred at 500 r / min for 30 min, followed by ultrasonic dispersion for 20 min. γ-glycidyl etheroxypropyltrimethoxysilane was added and stirred at 300 r / min for 10 min. Finally, polyether-modified polydimethylsiloxane was added and stirred at 200 r / min for 10 min. The mixture was then degassed under a vacuum of 0.08 MPa for 15 min to obtain Component A. Preparation of Component B: Polyetheramine, isophorone diamine and phenolic amine curing agent were stirred at 200 r / min for 15 min, benzyl alcohol was added and stirred at 200 r / min for 10 min, and finally 2,4,6-tris(2,4,6)-dimethylaminomethylphenol was added and stirred at 300 r / min for 5 min to obtain Component B.

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