An epoxy adhesive, its preparation method and application

Abstract

This invention relates to the field of concrete repair and protection technology, and particularly to an epoxy adhesive, its preparation method, and its application. The invention comprises 1: (0.35~0.65) Component A (65~85 parts of epoxy resin (modified epoxy resin EPCO-1103, epoxy resin HE-184, and / or epoxy resin EPM-386), 10~35 parts of reactive diluent (one or more of tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, and diglycidyl phthalic acid ester), 0.5~5 parts of isopropyl tris(dioctyl pyrophosphate) titanate, 0.5~3 parts of anti-settling agent, and 0.3~1.5 parts of defoamer), and Component B (55~80 parts of amine curing agent, 2~8 parts of accelerator, 5~20 parts of toughening agent, and 10~30 parts of non-reactive diluent). It has excellent freeze-thaw resistance, chloride ion penetration resistance, high bonding strength and yellowing resistance.

Description

Technical Field

[0001] This invention relates to the field of concrete repair and protection technology, and in particular to an epoxy adhesive, its preparation method, and its application. Background Technology

[0002] In high-altitude and cold regions, the alternating cycle of freezing temperatures in winter and thawing temperatures in spring can easily lead to freeze-thaw damage to concrete guardrails. In addition, the concrete guardrails are affected by de-icing agents (chloride salts) and collisions with snow removal equipment, resulting in carbonization, cracking, surface peeling, exposed rebar, and steel bar corrosion on the surface concrete. In severe cases, this can cause the guardrails to tilt or collapse, seriously affecting road safety. This is a typical problem in the use of guardrails in high-altitude and cold regions.

[0003] Currently, in regions such as the Tibet Autonomous Region and the Xinjiang Uygur Autonomous Region, ordinary epoxy putty is still used for repairing concrete guardrails, and some even use cement mortar or ordinary polymer mortar. These materials not only cannot withstand the damage of freeze-thaw cycles and the erosion of de-icing agents, but also easily change color under the intense sunlight at high altitudes, exhibiting yellowing and darkening. This not only affects the appearance of the product but also, to some extent, ages the internal structure of the material, making the repair material prone to cracking and peeling. There is a lack of research on epoxy putty currently available on the market that addresses freeze-thaw cycles and de-icing agent erosion. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides an epoxy adhesive, its preparation method and application, wherein the epoxy adhesive simultaneously possesses excellent freeze-thaw resistance, chloride ion penetration resistance, high bonding strength and yellowing resistance.

[0005] This invention provides an epoxy adhesive comprising separately packaged component A and component B; the mass ratio of component A to component B is 1:(0.35~0.65). By weight parts: Component A comprises 65-85 parts epoxy resin, 10-35 parts reactive diluent, 0.5-5 parts coupling agent, 0.5-3 parts anti-settling agent, and 0.3-1.5 parts defoamer; Component B comprises 55-80 parts of amine curing agent, 2-8 parts of accelerator, 5-20 parts of toughening agent, and 10-30 parts of non-reactive diluent; The epoxy resin includes modified epoxy resin EPCO-1103, and also includes epoxy resin HE-184 and / or epoxy resin EPM-386. The active diluent includes one or more of diglycidyl tetrahydrophthalic acid, diglycidyl hexahydrophthalic acid, and diglycidyl phthalic acid. The coupling agent includes isopropyltris(dioctylpyrophosphate)titanate.

[0006] Preferably, the epoxy resin further includes modified epoxy resin HE-184 and / or modified epoxy resin EPM-386.

[0007] Preferably, the anti-settling agent comprises fumed silica.

[0008] Preferably, the defoamer includes STA-XA530 and / or Tech-367N defoamer.

[0009] Preferably, the amine curing group includes Henster 1040 and / or XH-363.

[0010] Preferably, the accelerator comprises 2,4,6-tris(dimethylaminomethyl)phenol.

[0011] Preferably, the toughening agent includes one or more of liquid nitrile-40, hydroxyl-terminated polybutadiene liquid rubber, and amine-terminated liquid nitrile-butadiene rubber.

[0012] Preferably, the non-reactive diluent comprises D60 solvent oil and / or D80 solvent oil.

[0013] This invention also provides a method for preparing the epoxy adhesive described in the above technical solution, comprising the following steps: Epoxy resin, reactive diluent, coupling agent, anti-settling agent and defoamer are mixed to obtain component A; Component B is obtained by mixing amine curing agent, accelerator, toughening agent and non-reactive diluent.

[0014] This invention also provides the application of the epoxy adhesive described in the above technical solution in the field of concrete repair and surface protection.

[0015] This invention provides an epoxy adhesive comprising separately packaged component A and component B; the mass ratio of component A to component B is 1:(0.35~0.65); by mass parts: component A comprises 65~85 parts epoxy resin, 10~35 parts reactive diluent, 0.5~5 parts coupling agent, 0.5~3 parts anti-settling agent, and 0.3~1.5 parts defoamer; component B comprises 55~80 parts amine curing agent, 2~8 parts accelerator, and... The epoxy resin comprises 5-20 parts of toughening agent and 10-30 parts of non-reactive diluent; the epoxy resin includes modified epoxy resin EPCO-1103, and also includes epoxy resin HE-184 and / or epoxy resin EPM-386; the reactive diluent includes one or more of diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, and diglycidyl phthalate; the coupling agent includes isopropyltris(dioctyl pyrophosphate) titanate.

[0016] Compared with the prior art, the epoxy adhesive of the present invention has the following advantages: 1) Excellent freeze-thaw resistance: After repeated cycles of high and low temperatures, it still has good adhesion and will not cause the concrete base layer to be exposed or cracked. 2) Excellent resistance to chloride ion penetration: The epoxy adhesive can form a shielding layer through a high-density cross-linking reaction, which can effectively prevent chloride ions from penetrating and prevent corrosion of steel bars; 3) High bonding strength: It has extremely strong adhesion to concrete substrates and is not easy to fall off; 4) Excellent resistance to yellowing: heat resistant, oxidation resistant, and UV resistant. Attached Figure Description

[0017] Figure 1 This is a physical image of application example 1. Detailed Implementation

[0018] This invention provides an epoxy adhesive comprising separately packaged component A and component B; the mass ratio of component A to component B is 1:(0.35~0.65). By weight parts: Component A comprises 65-85 parts epoxy resin, 10-35 parts reactive diluent, 0.5-5 parts coupling agent, 0.5-3 parts anti-settling agent, and 0.3-1.5 parts defoamer; Component B comprises 55-80 parts of amine curing agent, 2-8 parts of accelerator, 5-20 parts of toughening agent, and 10-30 parts of non-reactive diluent; The epoxy resin includes modified epoxy resin EPCO-1103, and also includes epoxy resin HE-184 and / or epoxy resin EPM-386. The active diluent includes one or more of diglycidyl tetrahydrophthalic acid, diglycidyl hexahydrophthalic acid, and diglycidyl phthalic acid. The coupling agent includes isopropyltris(dioctylpyrophosphate)titanate.

[0019] In this invention, unless otherwise specified, all raw materials used in the preparation are commercially available products well known to those skilled in the art.

[0020] In this invention, the mass ratio of component A to component B is 1:(0.35~0.65), preferably 1:0.35, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, or 1:0.65. In an embodiment of this invention, the mass ratio of component A to component B can be 1:0.5.

[0021] Based on parts by weight, component A of the present invention comprises 65 to 85 parts of epoxy resin, preferably 65, 70, 75, 80, or 85 parts. In embodiments of the present invention, the parts by weight of epoxy resin in component A are 75 or 73 parts.

[0022] In this invention, the epoxy resin includes modified epoxy resin EPCO-1103, and further includes modified epoxy resin HE-184 and / or modified epoxy resin EPM-386. When the epoxy resin also includes modified epoxy resin HE-184 and / or modified epoxy resin EPM-386, this invention does not impose any special limitation on the amount relationship of each component in the epoxy resin; they can be mixed in any ratio. In embodiments of this invention, the epoxy resin includes modified epoxy resin EPCO-1103 and modified epoxy resin HE-184 in a mass ratio of 2:1, modified epoxy resin EPCO-1103 and modified epoxy resin EPM-386 in a mass ratio of 45:28, or modified epoxy resin EPCO-1103 and modified epoxy resin HE-184 in a mass ratio of 11:4.

[0023] In this invention, the modified epoxy resin EPCO-1103, modified epoxy resin HE-184, and modified epoxy resin EPM-386 are preferably purchased from Shanghai Luohe High-Tech Materials Co., Ltd.

[0024] In this invention, the modified epoxy resin EPCO-1103 is a functional epoxy resin for road waterproofing and infrastructure joint filling, with a high epoxy equivalent and high elasticity of the cured product; the modified epoxy resin HE-184 is an ultra-low viscosity, UV-resistant, and yellowing-resistant glycidyl ester-reinforced epoxy resin with excellent antioxidant and UV resistance, and good performance in high-altitude environments; the modified epoxy resin EPM-386 is a transparent, yellowing-resistant trifunctional epoxy resin with yellowing resistance and high heat resistance, and its cured product has high crosslinking density and high mechanical properties; by combining the modified epoxy resin EPCO-1103 with the modified epoxy resin HE-184 and / or the modified epoxy resin EPM-386, an epoxy resin with excellent comprehensive performance can be obtained.

[0025] Based on the mass fraction of the epoxy resin, component A of the present invention comprises 10 to 35 parts of an reactive diluent, preferably 10, 15, 20, 25, 30, or 35 parts by mass. In embodiments of the present invention, the mass fraction of the reactive diluent may be 18 or 20 parts.

[0026] In this invention, the reactive diluent preferably includes one or more of diglycidyl tetrahydrophthalate, diglycidyl hexahydrophthalate, and diglycidyl phthalate (DP). When the reactive diluent is two or more of the above-mentioned specific selections, this invention does not impose any special limitation on the ratio of the above-mentioned specific substances, and they can be mixed in any ratio. In the embodiments of this invention, the reactive diluent can be diglycidyl phthalate, diglycidyl phthalate and diglycidyl tetrahydrophthalate in a mass ratio of 1:1, or diglycidyl hexahydrophthalate.

[0027] In this invention, the tetrahydrophthalic acid diglycidyl ester, when used as an active diluent in combination with epoxy resin, can reduce viscosity and improve processability. Furthermore, the tetrahydrophthalic acid diglycidyl ester possesses excellent low-temperature resistance, enhancing the low-temperature resistance and bond strength of the final product. This characteristic effectively maintains material toughness at low temperatures, preventing coating cracking. The hexahydrophthalic acid diglycidyl ester has low viscosity, reducing system viscosity for easier application, and it participates in the reaction without leaving residues that affect performance, unlike inactive diluents. Diglycidyl hexahydrophthalate (DP) exhibits excellent weather resistance. Its structure does not contain benzene rings that are easily damaged by ultraviolet radiation, resulting in curing materials with excellent UV and arc resistance. After exposure to sunlight, rain, and de-icing agents, the coating is not prone to chalking or yellowing, providing long-lasting protection. It also possesses excellent low-temperature performance, making it ideal for handling freeze-thaw cycles caused by de-icing agents. It maintains toughness even at low temperatures, preventing coating cracking. In epoxy systems, DP can reduce viscosity and significantly improve low-temperature resistance and anti-aging properties, making it highly suitable for de-icing agent applications. DP contains highly reactive ester groups, exhibiting both rigid benzene rings and flexible ester bonds. At low temperatures, the rigid benzene rings provide structural strength, while the flexible ester bonds provide excellent toughness. This structure effectively prevents coating cracking due to alternating hot and cold temperatures in the low-temperature freeze-thaw environment caused by de-icing agents, maintaining the integrity of the coating.

[0028] Based on the mass fraction of the epoxy resin, component A of the present invention includes 0.5 to 5 parts of coupling agent, preferably 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 parts. In an embodiment of the present invention, the mass fraction of the coupling agent may be 3 parts.

[0029] In this invention, the isopropyltris(dioctylpyrophosphoryloxy)titanate can enhance the coating's resistance to corrosion by de-icing agents (chlorides). Its core mechanism is to protect the metal substrate by forming a dense passivation film. The isopropyltris(dioctylpyrophosphoryloxy)titanate can hydrolyze to generate titanium hydroxy compounds, which react with iron ions to form a dense conversion film on the substrate surface. This film can effectively prevent the penetration of corrosive media such as chloride ions, thereby significantly improving the coating's salt spray resistance and chemical resistance.

[0030] Based on the mass fraction of the epoxy resin, component A of the present invention includes 0.5 to 3 parts of an anti-settling agent, preferably 0.5, 1, 1.5, 2, 2.5, or 3 parts. In an embodiment of the present invention, the mass fraction of the anti-settling agent in component A is 3 parts.

[0031] In this invention, the anti-settling agent preferably comprises fumed silica.

[0032] In this invention, the anti-settling agent is used to prevent sedimentation. In the embodiments, fumed silica is selected as the anti-settling agent. When the liquid is stationary, the silanol groups on the surface are connected by hydrogen bonds to form a network structure. When the network is broken during stirring or construction, the viscosity is reduced, making it easier to operate. When the external force is removed, the network structure is quickly restored, thus preventing sedimentation.

[0033] Based on the mass fraction of the epoxy resin, component A of the present invention includes 0.3 to 1.5 parts of defoamer, preferably 0.3, 0.6, 0.9, 1.2, or 1.5 parts. In an embodiment of the present invention, the mass fraction of the defoamer in component A is 1.0 part.

[0034] In this invention, the defoamer preferably includes STA-XA530 and / or Tech-367N defoamer. When the defoamer is STA-XA530 and Tech-367N defoamer, this invention does not impose any special limitation on the specific ratio of the above substances; they can be mixed in any ratio. In an embodiment of this invention, the defoamer can be STA-XA530.

[0035] In this invention, the function of the defoamer is to defoam. In the examples, STA-XA530 defoamer is selected, which is a non-silicone defoamer with good compatibility, strong defoaming ability, fast speed, and can effectively break or suppress foam even at very low dosages.

[0036] Based on parts by weight, component B of the present invention comprises 55 to 80 parts of an amine curing agent, preferably 55, 60, 65, 70, 75, or 80 parts. In embodiments of the present invention, the parts by weight of the amine curing agent in component B may be 67 or 65 parts.

[0037] In this invention, the amine curing agent preferably includes Henster 1040 and / or XH-363. When the amine curing agent is Henster 1040 and XH-363, this invention does not impose any special limitation on the ratio of Henster 1040 and XH-363; they can be mixed in any ratio. In embodiments of this invention, the amine curing agent can be Henster 1040 and XH-363 in a mass ratio of 55:12, 47:20, or 55:10.

[0038] In this invention, Henster 1040 is used, which can cure rapidly in all seasons (including low-temperature conditions) and has high-temperature stability and good moisture resistance, making it suitable for surface-treated substrates. Its excellent chemical resistance also makes it suitable for harsh corrosive environments. XH-363 is used to give the cured coating high strength, high modulus, and an oily finish, while also exhibiting good resistance to distilled water, organic and inorganic acids, alkalis, and various organic solvents. Furthermore, the two components have good compatibility; their combination can combine their advantages and compensate for their respective shortcomings, resulting in a curing system with superior performance. This leads to comprehensive improvements in low-temperature workability, mechanical strength, and chemical resistance.

[0039] Based on the mass fraction of the amine curing agent, component B of the present invention includes 2 to 8 parts of an accelerator, preferably 2, 3, 4, 5, 6, 7, or 8 parts. In embodiments of the present invention, the mass fraction of the accelerator in component B is 3 or 5 parts.

[0040] In this invention, the accelerator preferably includes 2,4,6-tris(dimethylaminomethyl)phenol.

[0041] In this invention, the accelerator functions to promote the curing of epoxy resin. In the embodiments, 2,4,6-tris(dimethylaminomethyl)phenol is specifically selected as the accelerator, which has a superior effect on accelerating the curing of the epoxy system and the formation of the cross-linked network structure.

[0042] Based on the mass fraction of the amine curing agent, component B of the present invention includes 5 to 20 parts of toughening agent, preferably 5 parts, 10 parts, 15 parts, or 20 parts. In an embodiment of the present invention, the mass fraction of toughening agent in component B can be 10 parts.

[0043] In this invention, the toughening agent preferably includes one or more of liquid nitrile butadiene-40, hydroxyl-terminated polybutadiene liquid rubber, and amine-terminated liquid nitrile butadiene rubber, more preferably liquid nitrile butadiene-40, hydroxyl-terminated polybutadiene liquid rubber, or amine-terminated liquid nitrile butadiene rubber. When the toughening agent is two or more of the above-mentioned specific selections, this invention does not impose any special limitation on the ratio of the above specific substances, and they can be mixed in any ratio. In the embodiments of this invention, the toughening agent can be amine-terminated liquid nitrile butadiene rubber or hydroxyl-terminated polybutadiene liquid rubber.

[0044] In this invention, the toughening agent functions to improve the toughness of the coating, thereby enhancing its crack resistance and aging resistance. Specifically, the liquid nitrile-40 can significantly improve the aging resistance of the coating, and can also enhance the toughness and aging resistance of the epoxy system through physical blending; the terminal hydroxyl groups in the hydroxyl-terminated polybutadiene liquid rubber can react with epoxy groups to form a good interfacial bond, improving the coating's toughness and crack resistance; the terminal amine liquid nitrile rubber is a liquid nitrile copolymer with amino groups at the chain ends. Through the participation of active amino groups in the epoxy resin curing reaction to form a crosslinked network, the overall mechanical properties of the adhesive can be significantly improved, maintaining strength while improving flexibility.

[0045] Based on the mass fraction of the amine curing agent, component B of the present invention includes 10 to 30 parts of a non-reactive diluent, preferably 10, 15, 20, 25, or 30 parts. In an embodiment of the present invention, the mass fraction of the non-reactive diluent in component B can be 20 parts.

[0046] In this invention, the inactive diluent preferably includes D60 solvent oil and / or D80 solvent oil. When the inactive diluent is D60 solvent oil and D80 solvent oil, this invention does not impose any special limitation on the ratio of D60 solvent oil and D80 solvent oil; they can be mixed in any ratio. In an embodiment of this invention, the inactive diluent can be D60 solvent oil.

[0047] In this invention, the inactive diluent serves to reduce system viscosity and narrow the distillation range; it also facilitates the wetting and penetration of epoxy resin, thereby improving adhesion to the substrate. In the embodiments of this invention, D60 solvent oil is specifically selected because it is primarily a mixture of straight-chain alkanes (normal), branched-chain alkanes (isomers), and cycloalkanes, effectively reducing system viscosity, making it easier to mix evenly and apply smoothly. Furthermore, D60 solvent oil has a narrow distillation range and a moderate evaporation rate—neither too fast to cause foaming nor too slow to affect sanding. The low surface tension of D60 helps the epoxy resin better wet and penetrate the filler surface, making the putty denser and thus improving adhesion to the substrate. In addition, compared to toxic solvents such as xylene, it has a lower odor and less toxicity, effectively improving the construction environment.

[0048] The present invention also provides a method for preparing the epoxy adhesive described in the above technical solution, comprising the following steps: Epoxy resin, reactive diluent, coupling agent, anti-settling agent and defoamer are mixed to obtain component A; Component B is obtained by mixing amine curing agent, accelerator, toughening agent and non-reactive diluent.

[0049] This invention mixes epoxy resin, reactive diluent, coupling agent, anti-settling agent and defoamer to obtain component A.

[0050] In this invention, the mixing is preferably carried out under normal temperature and pressure conditions, which can be understood as not performing any additional heating or cooling, or pressurization or depressurization processes.

[0051] In this invention, the mixing process preferably involves mixing epoxy resin, reactive diluent, coupling agent, and defoamer, followed by a first stirring, and then adding an anti-settling agent for a second stirring. In this invention, the stirring speed of the first stirring is preferably 300-700 rpm, more preferably 300 rpm, 400 rpm, 500 rpm, 600 rpm, or 700 rpm; the stirring time is preferably 5-20 min, more preferably 5 min, 10 min, 15 min, or 20 min; the stirring speed of the second stirring is preferably 700-1200 rpm, more preferably 700 rpm, 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, or 1200 rpm; the stirring time is preferably 3-10 min, more preferably 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, or 10 min. In this invention, the stirring speed of the first stirring can be 500 rpm, and the stirring time can be 10 min; the stirring speed of the second stirring can be 1000 rpm, and the stirring time can be 5 min.

[0052] The preparation method of the present invention further includes mixing an amine curing agent, an accelerator, a toughening agent, and a non-reactive diluent to obtain component B.

[0053] In this invention, the mixing is preferably carried out under normal temperature and pressure conditions, which can be understood as not performing any additional heating or cooling, or pressurization or depressurization processes.

[0054] In this invention, the mixing is preferably carried out under stirring conditions, and the stirring speed is preferably 300~700 rpm, more preferably 300 rpm, 400 rpm, 500 rpm, 600 rpm or 700 rpm; the stirring time is preferably 5~20 min, more preferably 5 min, 10 min, 15 min or 20 min. In an embodiment of this invention, the stirring speed can be 500 rpm and the stirring time can be 10 min.

[0055] This invention also provides the application of the epoxy adhesive described in the above technical solution in the field of concrete repair and surface protection.

[0056] In this invention, the method for repairing and protecting the surface of a concrete substrate using the epoxy adhesive preferably includes the following steps: Component A and the first filler are mixed to obtain epoxy putty component A; Component B and the second filler are mixed to obtain epoxy putty component B; Mix component A and component B to obtain an epoxy adhesive; Epoxy adhesive and dried manufactured sand are mixed to obtain epoxy concrete slurry; After pre-coating the epoxy adhesive on the surface of the concrete substrate, the epoxy concrete slurry is filled into the repair position of the concrete substrate and then cured to obtain the pre-treated concrete substrate. The epoxy putty component A and the epoxy putty component B are mixed to obtain epoxy putty; The epoxy putty is applied to the pretreated concrete substrate and then cured.

[0057] The present invention mixes component A and the first filler to obtain epoxy putty component A.

[0058] In this invention, the first filler is preferably composed of 325-mesh fly ash, 800-mesh talc powder, and 800-mesh activated calcium carbonate in a mass ratio of 5:3:2.

[0059] In this invention, the mass ratio of component A to the first filler is preferably 1:1.3.

[0060] In this invention, the mixing is preferably carried out under stirring conditions, and the stirring speed is preferably 50-200 rpm, more preferably 50 rpm, 100 rpm, 150 rpm, or 200 rpm; the stirring time is preferably 10-30 min, more preferably 10 min, 15 min, 20 min, 25 min, or 30 min. In an embodiment of this invention, the stirring speed can be 100 rpm, and the stirring time can be 20 min.

[0061] The method of the present invention further includes mixing component B and the second filler to obtain epoxy putty component B.

[0062] In this invention, the second filler is preferably composed of 325-mesh fly ash, 800-mesh talc powder, and 800-mesh activated calcium carbonate in a mass ratio of 5:3:2.

[0063] In this invention, the mass ratio of component B and the second filler is preferably 1:1.3.

[0064] In this invention, the mixing is preferably carried out under stirring conditions, and the stirring speed is preferably 50-200 rpm, more preferably 50 rpm, 100 rpm, 150 rpm, or 200 rpm; the stirring time is preferably 10-30 min, more preferably 10 min, 15 min, 20 min, 25 min, or 30 min. In an embodiment of this invention, the stirring speed can be 100 rpm, and the stirring time can be 20 min.

[0065] The method of the present invention further includes mixing component A and component B to obtain an epoxy adhesive.

[0066] In this invention, the mixing is preferably carried out under stirring conditions. The stirring process is not particularly limited and can be performed using a process well-known to those skilled in the art. In embodiments of this invention, the mass ratio of component A to component B can be 1:0.5.

[0067] The method of the present invention further includes pre-coating the epoxy adhesive on the surface of the concrete substrate, filling the repair position of the concrete substrate with the epoxy concrete slurry, and then curing it to obtain the pre-treated concrete substrate.

[0068] In this invention, the pre-coating of the concrete substrate preferably includes surface treatment of the concrete substrate. This invention does not impose any special limitations on the surface treatment process. A process well known to those skilled in the art can be used to ensure that oil stains, water, dust, gravel and loose surface of the damaged concrete substrate are removed; and that rust is removed from the surface of exposed reinforcing bars.

[0069] In this invention, the pre-coating is preferably done by using a brush to apply a small amount of the epoxy adhesive to the damaged surface, which can increase adhesion.

[0070] In this invention, the preferred method for preparing the epoxy concrete slurry is to mix epoxy adhesive and dried manufactured sand to obtain the epoxy concrete slurry.

[0071] In this invention, the dried manufactured sand is preferably a 0-5mm graded dried manufactured sand.

[0072] In this invention, the mass ratio of the epoxy adhesive to the dried manufactured sand is preferably 1:(8~12), more preferably 1:8, 1:9, 1:10, 1:11 or 1:12.

[0073] In this invention, the mixing is preferably carried out under stirring conditions. This invention does not impose any special limitations on the stirring process, and any process well known to those skilled in the art can be used.

[0074] This invention does not impose any special limitations on the process of filling the epoxy concrete slurry into the repaired area of ​​the concrete substrate or the curing process; any process well known to those skilled in the art can be used. In embodiments of this invention, after filling the epoxy concrete slurry into the repaired area of ​​the concrete substrate, it is preferable to also apply masking tape; this invention does not impose any special limitations on the process of applying masking tape; any process well known to those skilled in the art can be used.

[0075] The method of the present invention further includes mixing the epoxy putty component A and the epoxy putty component B to obtain epoxy putty.

[0076] In this invention, the mixing is preferably carried out under stirring conditions, and the present invention does not impose any special limitations on the stirring process.

[0077] In this invention, the mass ratio of epoxy putty component A to epoxy putty component B can be 1:0.5.

[0078] After obtaining the epoxy putty, the present invention applies the epoxy putty to the pretreated concrete substrate and cures it.

[0079] In this invention, the coating method is preferably scraping. The scraping process is not particularly limited and can be performed using a process well-known to those skilled in the art. In this invention, the finishing height during scraping is preferably adjusted according to the extent of damage to the guardrail on site.

[0080] In this invention, the curing time is preferably 6 to 12 hours.

[0081] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0082] Example 1 Component A: Under normal temperature and pressure conditions, according to the following mass ratios, 50 parts of EPCO-1103 modified epoxy resin, 25 parts of HE-184 modified epoxy resin, 18 parts of diglycidyl phthalate, 3.0 parts of isopropyl tris(dioctyl pyrophosphate) titanate, and 1.0 part of STA-XA530 defoamer were added to the reactor and stirred at 500 rpm for 10 minutes; then, while stirring, 3.0 parts of fumed silica were slowly added. After the addition was completed, the stirring speed was adjusted to 1000 rpm, and stirring was continued for 5 minutes to obtain Component A. Component B: Under normal temperature and pressure conditions, according to the mass ratio, add 55 parts of Henster 1040 curing agent, 12 parts of XH-363 curing agent, 3 parts of DMP-30 accelerator, 10 parts of terminal amine liquid nitrile rubber, and 20 parts of non-reactive diluent D60 solvent oil to the reactor, and stir at 500 rpm for 10 minutes to obtain component B.

[0083] Example 2 Component A: Under normal pressure and at 50℃, 45 parts of EPCO-1103 modified epoxy resin, 28 parts of EPM-386 modified epoxy resin, 10 parts each of diglycidyl phthalate and tetrahydrodiglycidyl phthalate, 3.0 parts of isopropyl tris(dioctylpyrophosphate)titanate, and 1.0 part of STA-XA530 defoamer were added to the reactor and stirred at 500 rpm for 10 minutes. Then, while stirring, 3.0 parts of fumed silica were slowly added. After the addition was completed, the stirring speed was adjusted to 1000 rpm, and stirring was continued for 5 minutes to obtain Component A. Component B: Under normal temperature and pressure conditions, add 47 parts of Henster 1040 curing agent, 20 parts of XH-363 curing agent, 3 parts of DMP-30 accelerator, 10 parts of terminal amine liquid nitrile rubber, and 20 parts of non-reactive diluent D60 solvent oil to the reactor according to the mass ratio, and stir at 500 rpm for 10 minutes to obtain Component B.

[0084] Example 3 Component A: Under normal pressure and at 50℃, 55 parts of EPCO-1103 modified epoxy resin, 20 parts of HE-184 modified epoxy resin, 18 parts of diglycidyl hexahydrophthalate, 3.0 parts of isopropyl tris(dioctyl pyrophosphate)titanate, and 1.0 part of STA-XA530 defoamer were added to the reactor according to the following mass ratio. The mixture was stirred at 500 rpm for 10 minutes. Then, 3.0 parts of fumed silica were slowly added while stirring. After the addition was completed, the stirring speed was adjusted to 1000 rpm, and stirring was continued for 5 minutes to obtain Component A. Component B: Under normal temperature and pressure conditions, add 55 parts of Henster 1040 curing agent, 10 parts of XH-363 curing agent, 5 parts of DMP-30 accelerator, 10 parts of hydroxyl-terminated polybutadiene liquid rubber, and 20 parts of non-reactive diluent D60 solvent oil to the reactor according to the mass ratio, and stir at 500 rpm for 10 minutes to obtain Component B.

[0085] Comparative Example 1 Component A: Under normal temperature and pressure conditions, according to the following mass ratios, 50 parts of bisphenol A epoxy resin, 25 parts of bisphenol F epoxy resin, 18 parts of diglycidyl phthalate, 3.0 parts of isopropyl tris(dioctyl pyrophosphate) titanate, and 1.0 part of STA-XA530 defoamer were added to the reactor and stirred at 500 rpm for 10 minutes; then, while stirring, 3.0 parts of fumed silica were slowly added. After the addition was completed, the stirring speed was adjusted to 1000 rpm, and stirring was continued for 5 minutes to obtain Component A. Component B: Under normal temperature and pressure conditions, 55 parts by weight of Henster 1040 curing agent, 12 parts by weight of XH-363 curing agent, 3 parts by weight of DMP-30 accelerator, 10 parts by weight of terminal amine-based liquid nitrile rubber, and 20 parts by weight of non-reactive diluent D60 solvent oil were added to a reaction vessel and stirred at 500 rpm for 10 minutes to obtain component B. Comparative Example 2 Component A: Under normal temperature and pressure conditions, according to the following mass ratios, 50 parts of EPCO-1103 modified epoxy resin, 25 parts of HE-184 modified epoxy resin, 18 parts of AGE (C12-14 alkyl glycidyl ether), 3.0 parts of isopropyl tris(dioctyl pyrophosphate) titanate, and 1.0 part of STA-XA530 defoamer were added to the reactor and stirred at 500 rpm for 10 minutes; then, while stirring, 3.0 parts of fumed silica were slowly added. After the addition was completed, the stirring speed was adjusted to 1000 rpm, and stirring was continued for 5 minutes to obtain Component A. Component B: Under normal temperature and pressure conditions, according to the mass ratio, add 55 parts of Henster 1040 curing agent, 12 parts of XH-363 curing agent, 3 parts of DMP-30 accelerator, 10 parts of terminal amine liquid nitrile rubber, and 20 parts of non-reactive diluent D60 solvent oil to the reactor, and stir at 500 rpm for 10 minutes to obtain component B.

[0086] Comparative Example 3 Component A: Under normal temperature and pressure conditions, according to the mass ratio, 50 parts of EPCO-1103 modified epoxy resin, 25 parts of HE-184 modified epoxy resin, 18 parts of diglycidyl phthalate, and 1.0 part of STA-XA530 defoamer were added to the reactor and stirred at 500 rpm for 10 minutes; then, while stirring, 3.0 parts of fumed silica were slowly added. After the addition was completed, the stirring speed was adjusted to 1000 rpm, and stirring was continued for 5 minutes to obtain Component A. Component B: Under normal temperature and pressure conditions, add 67 parts of T31 curing agent, 3 parts of DMP-30 accelerator, 10 parts of terminal amine liquid nitrile rubber, and 20 parts of non-reactive diluent D60 solvent oil to the reaction vessel according to the mass ratio, and stir at 500 rpm for 10 minutes to obtain component B.

[0087] Comparative Example 4 The epoxy putty (Guangzhou Maichen Epoxy Putty MAX500N) sold in the market is obtained by mixing component A and component B evenly in a 2:1 ratio.

[0088] Application Example 1 Preparation of epoxy putty: Components A and B of the epoxy adhesive described in Example 1 were mixed with fillers at a mass ratio of 1:1.3 and stirred at 100 rpm for 20 min in a reactor to obtain epoxy putty components A and B. The filler consisted of 325-mesh fly ash, 800-mesh talc powder, and 800-mesh activated calcium carbonate, in a mass ratio of 5:3:2.

[0089] Surface preparation: Remove oil, water, dust, gravel and loose surface layer from the damaged concrete guardrail surface, and remove rust from exposed steel bars.

[0090] Pre-coating the substrate: Weigh appropriate amounts of components A and B according to the epoxy adhesive ratio of A:B=1:0.5 and stir evenly. Take a small amount of the stirred epoxy adhesive and use a brush to pre-coat the damaged surface of the guardrail to increase adhesion.

[0091] Preparation of epoxy concrete: Mix the well-stirred epoxy adhesive and 0-5mm graded dry manufactured sand at a mass ratio of 1:10, and then fill the repaired area with the mixed epoxy concrete.

[0092] Finishing: After applying masking tape and waiting for the epoxy concrete to cure, mix the epoxy putty components A and B evenly in a 1:0.5 ratio, and then apply the epoxy putty to the surface of the concrete guardrail. The finishing height is adjusted according to the damage to the guardrail on site, and is generally 40cm high.

[0093] Maintenance: After finishing, cure at 15℃ for 10 hours before traffic can be developed (see actual product image). Figure 1 As shown, a and b are the same road segment, located on the Altay Road overpass, from north to south at the bridge in front of the Zhongrixu Gas Station.

[0094] Application Example 2 Referring to Application Example 1, the difference is that components A and B of the epoxy adhesive described in Example 1 are replaced with components A and B of the epoxy adhesive described in Example 2, respectively, to obtain epoxy putty.

[0095] Application Example 3 Referring to Application Example 1, the difference is that components A and B of the epoxy adhesive described in Example 1 are replaced with components A and B of the epoxy adhesive described in Example 3, respectively, to obtain epoxy putty.

[0096] Application Example 4 The epoxy adhesive components A and B of Example 1 were mixed evenly at a mass ratio of 1:0.5. Then, the mixed epoxy adhesive and 0-5mm graded dry manufactured sand were mixed evenly at a mass ratio of 1:10 to obtain epoxy concrete.

[0097] Application Example 5 Referring to Application Example 4, the difference is that epoxy adhesive components A and B in Example 1 are replaced with epoxy adhesive components A and B in Example 2 to obtain epoxy concrete.

[0098] Application Example 6 Referring to Application Example 4, the difference is that epoxy adhesive components A and B in Example 1 are replaced with epoxy adhesive components A and B in Example 3 to obtain epoxy concrete.

[0099] Comparative Application Example 1 Referring to Application Example 1, the difference is that components A and B of the epoxy adhesive described in Example 1 are replaced with components A and B of the epoxy adhesive described in Comparative Example 1, respectively, to obtain epoxy putty.

[0100] Comparative Application Example 2 Referring to Application Example 2, the difference is that components A and B of the epoxy adhesive described in Example 2 are replaced with components A and B of the epoxy adhesive described in Comparative Example 2, respectively, to obtain epoxy putty.

[0101] Comparative Application Example 3 Referring to Application Example 3, the difference is that components A and B of the epoxy adhesive described in Example 3 are replaced with components A and B of the epoxy adhesive described in Comparative Example 3, respectively, to obtain epoxy putty.

[0102] Comparative Application Example 4 Referring to Application Example 4, the difference is that components A and B of the epoxy adhesive described in Example 1 are replaced with components A and B of the epoxy adhesive described in Comparative Example 1, respectively, to obtain epoxy concrete.

[0103] Comparative Application Example 5 Referring to Application Example 5, the difference is that components A and B of the epoxy adhesive described in Example 2 are replaced with components A and B of the epoxy adhesive described in Comparative Example 2, respectively, to obtain epoxy concrete.

[0104] Comparative Application Example 6 Referring to Application Example 6, the difference is that components A and B of the epoxy adhesive described in Example 2 are replaced with components A and B of the epoxy adhesive described in Comparative Example 3, respectively, to obtain epoxy concrete. Test Example Table 1 shows the test standards and performance parameters of the epoxy putty described in Application Examples 1-3, Comparative Application Examples 1-3, and Comparative Example 4.

[0105] As shown in Table 1, the epoxy putty prepared by the epoxy adhesive described in this invention possesses excellent resistance to yellowing, freeze-thaw resistance, salt spray resistance, and high bonding strength. According to GB / T1766-2008 "Rating Method for Aging of Paint and Varnish Coatings," the yellowing resistance of the epoxy putty was determined. It can be seen that Application Examples 1-3 showed no discoloration after 500 hours of xenon lamp irradiation, while Application Example 1 and Comparative Example 4, after the same test, showed obvious discoloration. This indicates that the yellowing resistance significantly decreased after replacing the modified epoxy resin. According to GB / T50728-2011 "Technical Specification for Safety Appraisal of Strengthening Materials for Engineering Structures," after 50 freeze-thaw cycles at -25℃ for 8 hours and 35℃ for 8 hours, the tensile shear strength of Application Examples 1-3 decreased by less than 2.0% compared to the short-term test results at room temperature. In contrast, Application Example 2 and Comparative Example 4, after the same test, showed a shear strength reduction rate exceeding 5%. According to JG / T 25-2017 "Test Method for Temperature Resistance of Architectural Coatings", after immersion in 25°C constant temperature water for 18 hours, and 50 freeze-thaw cycles at -20°C for 3 hours and 50°C for 3 hours, Application Examples 1-3 did not exhibit chalking, cracking, blistering, peeling, or significant discoloration. However, Comparative Application Example 2 and Comparative Example 4, after the same test, showed cracking, blistering, or chalking. This indicates that the epoxy putty prepared in Examples 1-3 possesses excellent freeze-thaw resistance. Replacing the modified epoxy resin or reactive diluent of this invention significantly reduced the freeze-thaw resistance. After 1000 hours of salt spray treatment, Application Examples 1-3 showed a strength reduction rate of less than 2.5% compared to the control group without salt spray treatment. In contrast, Comparative Application Example 3 and Comparative Example 4, after the same test, showed a strength reduction rate exceeding 5%, and Comparative Application Example 3 exhibited cracking and delamination. This demonstrates that the salt spray resistance of Application Examples 1-3 was significantly improved after the addition of the coupling agent (corrosion inhibitor).

[0106] Table 2. Performance of the epoxy concrete described in Application Examples 4-6 and Comparative Application Examples 4-6

[0107] As shown in Table 2, the epoxy concrete prepared by this invention possesses excellent freeze-thaw resistance, acid and alkali resistance, and chloride salt corrosion resistance. After 100 freeze-thaw cycles at -18℃ for 4 hours and at 20℃ for 4 hours, the mass loss rate of Application Examples 4-6 did not exceed 2%, and the strength loss rate did not exceed 5%. In contrast, the mass loss rate of Comparative Application Examples 4-6 all exceeded 5%, and the strength loss rate of Comparative Application Example 5 reached 17.7%, which, although meeting the standard requirement of ≤25, was significantly higher than that of Application Examples 4-6. After immersion in acid or alkali for 168 hours, the strength loss rate of Application Examples 4-6 was less than 10%; while the strength loss rate of Comparative Application Examples 4-6, although not exceeding the technical requirement of 30%, all exceeded 10%, and was approximately twice that of Application Examples 4-6. The resistance of epoxy concrete to chloride ion penetration was measured by the electrical flux method. The results showed that the electrical flux of application examples 4 to 6 was all below 1000C. Although the electrical flux of application examples 4 to 6 did not exceed 1000C, it was significantly higher than that of application examples 4-6. In contrast, the electrical flux of application example 6 was much greater than that of application examples 1 to 3 and exceeded 1000C, indicating that application examples 4 to 6 have good resistance to chloride ion penetration.

[0108] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An epoxy adhesive, characterized in that, It includes separately packaged component A and component B; the mass ratio of component A to component B is 1:(0.35~0.65); By weight parts: Component A comprises 65-85 parts epoxy resin, 10-35 parts reactive diluent, 0.5-5 parts coupling agent, 0.5-3 parts anti-settling agent, and 0.3-1.5 parts defoamer; Component B comprises 55-80 parts of amine curing agent, 2-8 parts of accelerator, 5-20 parts of toughening agent, and 10-30 parts of non-reactive diluent; The epoxy resin includes modified epoxy resin EPCO-1103, and also includes epoxy resin HE-184 and / or epoxy resin EPM-386. The active diluent includes one or more of diglycidyl tetrahydrophthalic acid, diglycidyl hexahydrophthalic acid, and diglycidyl phthalic acid. The coupling agent includes isopropyltris(dioctylpyrophosphate)titanate.

2. The epoxy adhesive as described in claim 1, characterized in that, The epoxy resin also includes modified epoxy resin HE-184 and / or modified epoxy resin EPM-386.

3. The epoxy adhesive as described in claim 1, characterized in that, The anti-settling agent includes fumed silica.

4. The epoxy adhesive as described in claim 1, characterized in that, The defoamer includes STA-XA530 and / or Tech-367N defoamer.

5. The epoxy adhesive as described in claim 1, characterized in that, The amine curing group includes Henster 1040 and / or XH-363.

6. The epoxy adhesive as described in claim 1, characterized in that, The accelerator includes 2,4,6-tris(dimethylaminomethyl)phenol.

7. The epoxy adhesive as described in claim 1, characterized in that, The toughening agent includes one or more of liquid nitrile-40, hydroxyl-terminated polybutadiene liquid rubber, and amine-terminated liquid nitrile-butadiene rubber.

8. The epoxy adhesive as described in claim 1, characterized in that, The inactive diluents include D60 solvent oil and / or D80 solvent oil.

9. A method for preparing the epoxy adhesive according to any one of claims 1 to 8, characterized in that, Includes the following steps: Epoxy resin, reactive diluent, coupling agent, anti-settling agent and defoamer are mixed to obtain component A; Component B is obtained by mixing amine curing agent, accelerator, toughening agent and non-reactive diluent.

10. The application of the epoxy adhesive according to any one of claims 1 to 8 in the field of concrete repair and surface protection.

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