A low-temperature epoxy resin infiltration consolidating agent and its preparation method and application

Abstract

The present application relates to the technical field of epoxy resin curing agents, and specifically discloses a low-temperature epoxy resin infiltration consolidating agent, its preparation method and application. The low-temperature epoxy resin infiltration consolidating agent provided by the present application comprises the following components in parts by weight: Component A: 10-15 parts of free radical active diluent, 10-20 parts of surfactant; Component B: 35-33 parts of modified amine; Component C: 5-10 parts of low-temperature curing accelerator; wherein the modified amine is obtained by polymerization of alicyclic amine and acrylonitrile; the present application also provides a low-temperature epoxy resin prepared from the low-temperature epoxy resin infiltration consolidating agent and epoxy resin. The low-temperature epoxy resin infiltration consolidating agent provided by the present application has good low-temperature activity, good compatibility with epoxy resin, and can make the epoxy resin cured product have excellent toughness and permeability, thereby meeting the adaptability, efficiency and quality requirements of epoxy resin coating construction in low-temperature environments.

Description

Technical Field

[0001] The present application relates to the technical field of epoxy resin curing agents, and in particular to a low-temperature epoxy resin infiltration consolidating agent, a preparation method thereof, and an application thereof. Background Art

[0002] Epoxy resin curing agents are a crucial component in epoxy resin applications, promoting the curing of epoxy resins to form materials with excellent properties. However, conventional epoxy resin curing agents typically require relatively high curing temperatures. Room-temperature epoxy resin curing agents can take considerable time to cure at low temperatures, or even fail to cure at all. This significantly limits their application in low-temperature environments or on temperature-sensitive substrates.

[0003] In recent years, to address the high-temperature curing issues of traditional epoxy resin curing agents, researchers have achieved some success by modifying the curing agent or adding catalysts to lower the curing temperature. Currently, reported low-temperature epoxy resin curing agents include aliphatic amine curing agents, thiol curing agents, phenalkamine curing agents, and imidazole curing agents. However, while these low-temperature epoxy resin curing agents lower the curing temperature of epoxy resin, they all have their own shortcomings, such as poor compatibility with the resin, slow curing speed, and unsatisfactory curing results. Furthermore, these low-temperature epoxy resin curing agents do not consider the permeability of epoxy resin. Summary of the Invention

[0004] In order to overcome the problems of poor compatibility with resin, slow curing speed, unsatisfactory curing effect and epoxy resin permeability of low-temperature epoxy resin in the prior art, the present application provides a low-temperature epoxy resin infiltration consolidating agent and its preparation method and application.

[0005] In a first aspect, the present application provides a low-temperature epoxy resin infiltration consolidating agent, which adopts the following technical solution:

[0006] A low-temperature epoxy resin infiltration consolidating agent comprises the following components in parts by weight:

[0007] Component A: 10-15 parts of free radical active diluent, 10-20 parts of surfactant;

[0008] Component B: 35-33 parts of modified amine;

[0009] Component C: 5-10 parts of low temperature curing accelerator;

[0010] Wherein, the modified amine is obtained by polymerizing alicyclic amine and acrylonitrile.

[0011] The present application provides a low-temperature epoxy resin penetrating consolidating agent, which can react with the groups in the epoxy resin to form an interpenetrating network structure and improve the toughness of the epoxy resin. The free radical active diluent can improve the fluidity of the epoxy resin and reduce the viscosity of the system, so that the components of the consolidating agent and the resin are mixed more evenly; the surfactant can improve the permeability of the epoxy resin cured product and improve the adhesion of the epoxy resin to the substrate; the modified amine prepared from alicyclic amine and acrylonitrile polymer has good compatibility with the epoxy resin, making the interpenetrating network structure more uniform and dense, and the toughness of the epoxy resin cured product is better; the low-temperature curing accelerator is to increase the low-temperature curing rate of the epoxy resin by introducing a chemical inorganic heat source and shorten the curing time. Therefore, the low-temperature epoxy resin penetrating consolidating agent provided by the present application has good low-temperature activity and good compatibility with the resin. The obtained epoxy resin cured product has good toughness and permeability, and can meet the adaptability, efficiency and quality requirements of epoxy resin coating construction under low-temperature environment.

[0012] Optionally, the alicyclic amine is selected from isophoronediamine and 4,4'-diaminodicyclohexylmethane; and the surfactant is selected from acetylene glycol, acetylene glycol, polyoxyethylene ether, polyoxyethylene ester and sulfonate.

[0013] Optionally, the surfactant is a mixture of acetylene glycol and polyoxyethylene ester in a weight ratio of 1:(0.3-0.7).

[0014] In some embodiments, the weight ratio of the acetylene glycol to the polyoxyethylene ester is 1:(0.3-0.4), 1:(0.3-0.5), 1:(0.3-0.6), 1:(0.3-0.7), 1:(0.4-0.5), 1:(0.4-0.6), 1:(0.4-0.7), 1:(0.5-0.6), 1:(0.5-0.7) or 1:(0.6-0.7).

[0015] In a specific embodiment, the weight ratio of the acetylene glycol to the polyoxyethylene ester is 1:0.3, 1:0.4, 1:0.5, 1:0.6 or 1:0.7.

[0016] Optionally, the free radical active diluent is selected from 1,6-hexanediol methoxy monoacrylate and ethoxylated neopentyl glycol methoxy monoacrylate.

[0017] Optionally, the low-temperature curing accelerator is selected from one or more of magnesium oxide, aluminum oxide, zinc oxide, aluminum hydroxide, aluminum sulfate and iron sulfate.

[0018] Optionally, the low-temperature curing accelerator is magnesium oxide; the magnesium oxide includes magnesium oxide with a fineness of 110-130 mesh and magnesium oxide with a fineness of 170-190 mesh.

[0019] Optionally, the weight ratio of the magnesium oxide with a fineness of 110-130 meshes to the magnesium oxide with a fineness of 170-190 meshes is 1:(0.25-0.65).

[0020] In this application, magnesium oxide can be used as a chemical inorganic heat source to react with epoxy groups in epoxy resin at relatively low temperatures, thereby effectively increasing the curing speed of epoxy resin. The inventors of this application have discovered that the particle size and ratio of magnesium oxide affect the curing rate of epoxy resin. Through experimental research, they found that controlling the particle size and ratio of magnesium oxide within the above ranges can result in a low-temperature epoxy resin infiltration consolidating agent that shortens the curing time of epoxy resin.

[0021] In some embodiments, the weight ratio of the magnesium oxide with a fineness of 110-130 mesh to the magnesium oxide with a fineness of 170-190 mesh can be 1:(0.25-0.45) or 1:(0.45-0.65).

[0022] In a specific embodiment, the weight ratio of the magnesium oxide with a fineness of 110-130 meshes to the magnesium oxide with a fineness of 170-190 meshes can also be 1:0.25, 1:0.45 or 1:0.65.

[0023] In the second aspect, the present application provides a method for preparing a low-temperature epoxy resin infiltration consolidating agent, comprising the following steps: adding component A to component B under stirring, and reacting at a constant temperature of 60-80°C for 1-2 hours; then adding component C thereto under stirring, mixing evenly, to obtain a low-temperature epoxy resin infiltration consolidating agent.

[0024] In a third aspect, the present application provides a low-temperature epoxy resin, comprising the low-temperature epoxy resin infiltration consolidating agent and epoxy resin.

[0025] Optionally, the weight ratio of the low-temperature epoxy resin infiltration consolidating agent to the epoxy resin is 1:(0.9-1.2).

[0026] In summary, this application has the following beneficial effects:

[0027] 1. The present application provides a low-temperature epoxy resin penetrating consolidating agent. The above-mentioned low-temperature epoxy resin penetrating consolidating agent has good low-temperature activity and good compatibility with epoxy resin. The epoxy resin cured product prepared using it has good toughness and permeability, and can meet the adaptability, efficiency and quality requirements of epoxy resin coating construction in low-temperature environments.

[0028] 2. This application further uses a mixture of acetylene glycol and polyoxyethylene ester in a weight ratio as a surfactant, and the resulting low-temperature epoxy resin has better toughness and permeability. The shear strength of the epoxy resin cured product is 8.1-8.4 MPa, the elongation at break is 7.0-7.4%, and the penetration depth in concrete is 5.8-6.3 mm.

[0029] 3. This application further uses a mixture of 120 mesh and 180 mesh magnesium oxide as a low-temperature curing accelerator in the low-temperature epoxy resin infiltration consolidator, which can further increase the curing rate of the epoxy resin, making the gel time as low as 42-46 minutes and the complete curing time as low as 16 hours. DETAILED DESCRIPTION

[0030] The present application provides a low-temperature epoxy resin infiltration consolidating agent, comprising the following components in parts by weight: component A: 10-15 parts of a free radical active diluent and 10-20 parts of a surfactant; component B: 35-33 parts of a modified amine; and component C: 5-10 parts of a low-temperature curing accelerator.

[0031] The radical-active diluent is selected from 1,6-hexanediol methoxy monoacrylate and ethoxylated neopentyl glycol methoxy monoacrylate. The surfactant is selected from acetylenic diols, acetylenic glycols, polyoxyethylene ethers, polyoxyethylene esters, and sulfonates. Furthermore, the surfactant is a mixture of acetylenic diols and polyoxyethylene esters in a weight ratio of 1:(0.3-0.7). The modified amine is obtained by polymerizing a cycloaliphatic amine and acrylonitrile; the cycloaliphatic amine is selected from isophoronediamine and 4,4'-diaminodicyclohexylmethane. The low-temperature curing accelerator is selected from magnesium oxide, aluminum oxide, zinc oxide, aluminum hydroxide, aluminum sulfate and ferric sulfate; further, the low-temperature curing accelerator is magnesium oxide; the magnesium oxide includes magnesium oxide with a fineness of 110-130 mesh and magnesium oxide with a fineness of 170-190 mesh; further, the weight ratio of the magnesium oxide with a fineness of 110-130 mesh and the magnesium oxide with a fineness of 170-190 mesh is 1:(0.25-0.65).

[0032] The preparation method of the above-mentioned low-temperature epoxy resin infiltration consolidating agent includes the following steps: adding component A to component B under stirring, and reacting at a constant temperature of 60-80°C for 1-2 hours; then adding component C under stirring, mixing evenly, to obtain a low-temperature epoxy resin infiltration consolidating agent.

[0033] The present application also provides a low-temperature epoxy resin, which is prepared by mixing a low-temperature epoxy resin infiltration consolidating agent and an epoxy resin. The weight ratio of the low-temperature epoxy resin infiltration consolidating agent to the epoxy resin is 1:(0.9-1.2).

[0034] In this application, unless otherwise specified, the raw materials, reagents, solvents, etc. can be obtained from commercial sources.

[0035] The present application is further described in detail below with reference to preparation examples, embodiments and performance testing experiments.

[0036] Preparation Example 1

[0037] Preparation Example 1 provides a low-temperature epoxy resin infiltration consolidating agent.

[0038] The preparation method of the low-temperature epoxy resin infiltration consolidating agent comprises the following steps:

[0039] (1) Weigh 10 g of 1,6-hexanediol methoxy monoacrylate (HDOMEMA) (purchased from Hubei Shineng Chemical Technology Co., Ltd.), 15 g of acetylene glycol (purchased from American Gas Chemical Company), 40 g of modified amine, and 5 g of magnesium oxide (120 mesh) respectively.

[0040] (2) adding 1,6-hexanediol methoxy monoacrylate and acetylenic diol to the modified amine under stirring, and reacting at 70° C. for 1.5 hours to obtain premix A;

[0041] (3) Then, magnesium oxide is added to the premix A under stirring, and mixed evenly to obtain a low-temperature epoxy resin infiltration consolidating agent.

[0042] The modified amine used in Preparation Example 1 is obtained by polymerization of 4,4'-diaminodicyclohexylmethane (PACM) and acrylonitrile. The preparation method is as follows: 4,4'-diaminodicyclohexylmethane (PACM) is poured into a reaction vessel and the temperature is raised to 70°C during stirring; acrylonitrile is added dropwise while stirring. After the addition is complete, the temperature is maintained at 60-90°C for 1-2 hours, and then the temperature is increased to 120°C and maintained for 1-2 hours.

[0043] Preparation Example 2

[0044] Preparation Example 2 provides a low-temperature epoxy resin infiltration consolidating agent.

[0045] The difference between the above Preparation Example and Preparation Example 1 is that the modified amine used in Preparation Example 2 is obtained by polymerization of isophorone diamine (IPDA) and acrylonitrile. The preparation method is as follows: acrylonitrile is slowly added dropwise to an equivalent amount of IPDA at room temperature under argon protection and stirring, with the temperature controlled not to exceed 50°C. After the addition is complete, the reaction is carried out at room temperature for 24 hours, then at 50°C for 15 hours, and finally, the mixture is vacuum dried at 60°C to constant weight.

[0046] Preparation Example 3-9

[0047] Preparation Examples 3-9 each provide a low-temperature epoxy resin infiltration consolidating agent.

[0048] The difference between the above preparation example and preparation example 1 is: the type of surfactant, as shown in Table 1 below.

[0049] Table 1 Types of surfactants in low-temperature epoxy resin infiltration consolidating agents of Preparation Example 1 and Preparation Examples 3-9

[0050]

[0051]

[0052] Preparation Examples 10-15

[0053] Preparation Examples 10-15 respectively provide a low-temperature epoxy resin infiltration consolidating agent.

[0054] The difference between the above preparation example and preparation example 5 is the fineness of magnesium oxide, as shown in Table 2 below.

[0055] Table 2 Fineness of magnesium oxide in low-temperature epoxy resin infiltration consolidating agent of Preparation Example 5 and Preparation Examples 10-15

[0056] Preparation Example Fineness of magnesium oxide 5 120 mesh 10 150 mesh 11 A mixture of 120 mesh and 180 mesh in a weight ratio of 1:0.25 12 A mixture of 120 mesh and 180 mesh in a weight ratio of 1:0.45 13 A mixture of 120 mesh and 180 mesh in a weight ratio of 1:0.65 14 A mixture of 120 mesh and 150 mesh in a weight ratio of 1:0.45 15 A mixture of 100 mesh and 200 mesh in a weight ratio of 1:0.45

[0057] Examples 1-15

[0058] Examples 1-15 each provide a low-temperature epoxy resin.

[0059] The difference between the above embodiments is that the low-temperature epoxy resin infiltration consolidating agent used in Examples 1-15 is derived from Preparation Examples 1-15 respectively.

[0060] The preparation method of the low-temperature epoxy resin provided in Example 1-15 includes the following steps: mixing the low-temperature epoxy resin infiltration consolidating agent and bisphenol A epoxy resin (E44) in a weight ratio of 1:1 to obtain the low-temperature epoxy resin.

[0061] Comparative Example 1

[0062] Comparative Example 1 provides a low-temperature epoxy resin.

[0063] The difference between the comparative example and Example 1 is that the modified amine in the low-temperature epoxy resin infiltration consolidating agent is 4,4'-diaminodicyclohexylmethane.

[0064] Comparative Example 2

[0065] Comparative Example 2 provides a low-temperature epoxy resin.

[0066] The difference between the comparative example and Example 2 is that the modified amine in the low-temperature epoxy resin infiltration consolidating agent is isophorone diamine.

[0067] Comparative Example 3

[0068] Comparative Example 3 provides a low-temperature epoxy resin.

[0069] The difference between the comparative example and Example 1 is that the amount of magnesium oxide added is 0.

[0070] Comparative Example 4

[0071] Comparative Example 4 provides a low-temperature epoxy resin.

[0072] The difference between the comparative example and Example 1 is that the amount of acetylene glycol added is 0.

[0073] Performance testing

[0074] The performance of the low-temperature epoxy resins obtained in Examples 1-15 and Comparative Examples 1-4 was tested, and the results are shown in Table 3 below.

[0075] (1) Gel time: Refer to the test specification "Measurement Method for Gel Time of Epoxy Resins" (GB / T 12007.7-1989): A plunger of a certain shape and buoyancy is suspended in the resin. A driving mechanism causes it to perform simple harmonic motion in a vertical plane with a fixed amplitude. The plunger is adjusted so that it actually rises during the upward movement and falls freely at a speed no faster than the simple harmonic motion during the downward movement. The gel time is the time from the time when all the curing agent is added to the resin to the time when the resin gel is automatically detected to be just enough to support the force of the plunger's descent.

[0076] (2) Complete curing time: Use an indenter to apply a certain pressure to the sample surface, observe the time when the hardness no longer changes, and record the time.

[0077] (3) Tensile shear strength: Refer to the test specification "Determination of tensile shear strength of adhesives" (GB 7124-2008), the test specimen length is 250mm, width is 25mm, and thickness is 2mm. The bonding surface length of the specimen is 12.5mm, the thickness of the test plate is 1.6mm, and the shear force change rate is set between 8.3MPa and 9.8MPa per minute. The specimen is clamped symmetrically on the fixture, and the distance from the clamp to the nearest bonding end is 50mm. Gaskets can be used in the fixture to ensure that the force is within the bonding surface. The tensile testing machine is operated at a constant test speed, and the maximum load of the specimen shear failure is recorded as the failure load.

[0078] (4) Elongation at break: Refer to the standard "Test Method for Properties of Resin Castings" (GB / T 2567-2021). The test specimen is 250 mm long, 25 mm wide, and 2 mm thick. A static tensile load is applied uniformly along the axial direction of the specimen at a tensile speed of 2 mm / min until the specimen breaks or reaches the predetermined elongation. During the entire process, the load applied to the specimen and the elongation of the specimen are measured. The elongation within the gauge length at the time of specimen fracture is divided by the measured gauge length to obtain the elongation at break.

[0079] (5) Penetration depth: refer to the test specification "Epoxy Resin Waterproof Coating" (JCT2217-2014): cut the vertical surface of the specimen brushed with low-temperature epoxy resin, wet the concrete cut surface with water, select three points evenly at a distance of not less than 10m from the edge of the coating specimen on the cut surface, and measure the depth of low-temperature epoxy resin penetration into the concrete (from the coating surface to the yellow imprint part) with a vernier caliper. When the penetration depth is less than 2mm, it can be measured with a reading microscope.

[0080] Note: In the above test experiments, the curing environment temperature of each epoxy resin is -5℃.

[0081] Table 3 Performance test results of low-temperature epoxy resin

[0082]

[0083] According to the test results in Table 3, the low-temperature epoxy resins obtained in Examples 1-15 of the present application have a gel time of 42-57 min, a complete curing time of 16-20 h, a shear strength of 7.6-8.5 MPa, an elongation at break of 6.2-7.4%, and a penetration depth in concrete of 5.4-6.3 mm; while the low-temperature epoxy resins prepared in Comparative Examples 1-2 using 4,4'-diaminodicyclohexylmethane or isophoronediamine as modified amines have a shear strength of only 4.0-4.2 MPa and an elongation at break of only 3.6-3.9%; the low-temperature epoxy resin prepared in Comparative Example 3 without adding a low-temperature curing accelerator has a gel time of up to 112 min and a complete curing time of up to 28 h; the low-temperature epoxy resin prepared in Comparative Example 4 without adding a surfactant has a penetration depth in concrete of only 1.2 mm.

[0084] The test results of Example 1 and Examples 3-9 show that Example 1 uses only acetylene glycol as a surfactant, and the shear strength of the obtained low-temperature epoxy resin is 7.8 MPa, the elongation at break is 6.5%, and the penetration depth in concrete is 5.6 mm; while Examples 3-7 use a mixture of acetylene glycol and polyoxyethylene ester as a surfactant, and the shear strength of the obtained low-temperature epoxy resin is 8.1-8.4 MPa, the elongation at break is 7.0-7.4%, and the penetration depth in concrete is 5.8-6.3 mm; Example 8 uses a mixture of acetylene glycol and polyoxyethylene ester as a surfactant, and the shear strength of the obtained low-temperature epoxy resin is 7.9 MPa, the elongation at break is 6.8%, and the penetration depth in concrete is 5.7 mm; Example 8 uses a mixture of polyoxyethylene ester and polyoxyethylene ether as a surfactant, and the shear strength of the obtained low-temperature epoxy resin is 7.6 MPa, the elongation at break is 7.4%, and the penetration depth in concrete is 6.3 mm. Therefore, it is shown that the present application adopts a mixture of acetylene glycol and polyoxyethylene ester as a surfactant, and the resulting low-temperature epoxy resin has better toughness and permeability.

[0085] From the test results of Example 5 and Examples 10-15, it can be seen that Example 5 and Example 10 use magnesium oxide of a single particle size of 120 mesh or 150 mesh as a low-temperature curing accelerator, and the obtained low-temperature epoxy resin has a gel time of 53-55 min and a complete curing time of 17-19 h; Examples 11-13 use a mixture of 120 mesh and 180 mesh magnesium oxide as a low-temperature curing accelerator, and the obtained low-temperature epoxy resin has a gel time of 42-46 min and a complete curing time of 16 h; Example 14 uses a mixture of 120 mesh and 150 mesh magnesium oxide as a low-temperature curing accelerator, and the obtained low-temperature epoxy resin has a gel time of 54 min and a complete curing time of 18 h; Example 15 uses a mixture of 100 mesh and 200 mesh magnesium oxide as a low-temperature curing accelerator, and the obtained low-temperature epoxy resin has a gel time of 52 min and a complete curing time of 17 h. Therefore, it is shown that the present application uses a mixture of 120-mesh and 180-mesh magnesium oxide as a low-temperature curing accelerator in a low-temperature epoxy resin infiltration consolidating agent, which can further increase the curing rate of the epoxy resin and shorten its coagulation and curing time.

[0086] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the present invention. Therefore, such modifications and improvements, which do not depart from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A low-temperature epoxy resin infiltration consolidating agent, characterized in that: The composition comprises the following components in parts by weight: Component A: 10-15 parts of free radical active diluent and 10-20 parts of surfactant; Component B: 35-33 parts of modified amine; and Component C: 5-10 parts of low temperature curing accelerator; Wherein, the modified amine is obtained by polymerization of alicyclic amine and acrylonitrile; The low-temperature curing accelerator is magnesium oxide, and the magnesium oxide includes magnesium oxide with a fineness of 110-130 mesh and magnesium oxide with a fineness of 170-190 mesh in a weight ratio of 1: (0.25-0.65); The surfactant is selected from acetylenic glycols, polyoxyethylene ethers, polyoxyethylene esters and sulfonates.

2. The low-temperature epoxy resin infiltration consolidating agent according to claim 1, characterized in that: The alicyclic amine is selected from isophoronediamine and 4,4'-diaminodicyclohexylmethane.

3. The low-temperature epoxy resin infiltration consolidating agent according to claim 1, characterized in that: The surfactant is a mixture of acetylene glycol and polyoxyethylene ester in a weight ratio of 1:(0.3-0.7).

4. The low-temperature epoxy resin infiltration consolidating agent according to claim 1, characterized in that: The free radical active diluent is selected from 1,6-hexanediol methoxy monoacrylate and ethoxylated neopentyl glycol methoxy monoacrylate.

5. A method for preparing a low-temperature epoxy resin infiltration consolidating agent according to any one of claims 1 to 4, characterized in that: The following steps are involved: Add component A to component B under stirring, and react at a constant temperature of 60-80°C for 1-2 hours; then add component C under stirring, mix evenly, and obtain a low-temperature epoxy resin infiltration consolidating agent.

6. A low-temperature epoxy resin, characterized in that The invention comprises the low-temperature epoxy resin infiltration consolidating agent according to any one of claims 1 to 5 and an epoxy resin.

7. The low-temperature epoxy resin according to claim 6, characterized in that The weight ratio of the low-temperature epoxy resin infiltration consolidating agent to the epoxy resin is 1:(0.9-1.2).

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