High-strength shock-resistant two-component acrylate structural adhesive and preparation method thereof

Abstract

The invention discloses a high-strength shock-resistant bi-component acrylate structural adhesive, and belongs to the technical field of adhesives. The structural adhesive comprises a component A and a component B, and specifically comprises the following components in parts by weight: the component A: 65-70 parts of acrylate monomer; 20-23 parts of an elastomer; 3.5 to 5.2 parts of a toughening agent; 0.01 part of a stabilizer; 5 parts of a main accelerant; 0.5 part of a curing accelerator; 0.3 to 0.5 part of an adhesion promoter; 0.5 to 2 parts of an adhesion promoter; 0 to 0.0002 part of a pigment; a component B: 65-70 parts of an acrylate monomer; 21-24 parts of an elastomer; 1.2 parts of a stabilizer; 5 parts of peroxide; 2.8 to 4.8 parts of a toughening agent; and 0 to 0.0002 part of pigment. The invention also discloses a preparation method of the high-strength shock-resistant bi-component acrylate structural adhesive. The product is high in bonding strength and good in shock resistance, and the preparation method of the product is simple and easy to implement.

Description

Technical Field

[0001] The invention belongs to the technical field of adhesives, and in particular relates to a high-strength shock-resistant acrylic structural adhesive and a preparation method thereof. Background Art

[0002] Two-component acrylic structural adhesives are widely used in the automotive, machinery, electronics and other fields due to their excellent comprehensive performance. Two-component acrylic structural adhesives excel in fast curing, resistance to environmental aging, and high elasticity, making them suitable for bonding metals and composite materials. However, with the development of industrial technology, certain special application scenarios have placed higher demands on the performance of two-component acrylic structural adhesives. For example, key components such as the flat arm of the high-speed rail contact network need to maintain stable bonding under dynamic loads and long-term vibration environments. Existing acrylic adhesives have insufficient bonding strength on metal substrates such as red copper and have poor seismic performance. High-frequency vibrations can easily lead to interface peeling or cracking of the adhesive layer, seriously affecting equipment reliability.

[0003] Existing technologies improve toughness by adding toughening agents or adjusting monomer ratios, but this often sacrifices bonding strength. While traditional silane coupling agents can improve adhesion to some metals, their chemical bonding effectiveness is limited on less active surfaces like copper. Furthermore, few commercially available products incorporate systematic optimization for seismic performance, resulting in insufficient durability under vibration conditions.

[0004] Therefore, there is an urgent need to develop an acrylic structural adhesive that has ultra-high bonding strength, excellent seismic resistance and wide applicability to meet the stringent requirements of complex working conditions. Summary of the Invention

[0005] The present invention aims to solve the above problems and remedy the deficiencies of the prior art by providing a high-strength, shock-resistant acrylic two-component structural adhesive, comprising component A and component B. The specific weight parts are as follows: Component A includes: 65-70 parts of acrylate monomer; 20-23 parts of elastomer; 3.5-5.2 parts of toughening agent; 0.01 parts of stabilizer; 5 parts of main accelerator; 0.5 parts of curing accelerator; Adhesion promoter 0.3-0.5 parts; Adhesion promoter 0.5-2 parts; Pigment 0-0.0002 parts; Component B includes: 65-70 parts of acrylate monomer; 21-24 parts of elastomer; 1.2 parts of stabilizer; 5 parts of peroxide; 2.8-4.8 parts of toughening agent; Pigment 0-0.0002 parts.

[0006] Preferably, the acrylate monomer is at least one of methyl methacrylate, isobornyl methacrylate, methacrylic acid, hydroxyethyl methacrylate, hydroxypropyl methacrylate, 1,3-butylene glycol dimethacrylate, 2-phenoxyethyl methacrylate, tetrahydrofuranyl methacrylate, ethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

[0007] Preferably, the elastomer is at least one of nitrile rubber, chloroprene rubber, chlorosulfonated polyethylene, ABS, and MBS.

[0008] Preferably, the toughening agent is solvent-based polyurethane.

[0009] Preferably, the stabilizer is at least one of hydroquinone, hydroquinone, naphthoquinone, 2,6-di-tert-butyl-p-methylphenol, and EDTA sodium salt.

[0010] Preferably, the primary accelerator is at least one of monoethylamine, diethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, tetramethylthiourea, and ethylenethiourea.

[0011] Preferably, the peroxide is at least one of cumene hydroperoxide, benzoyl peroxide, and dicumyl hydroperoxide; and the curing accelerator is at least one of sodium o-benzoylsulfonimide and acetylacetone metal salts.

[0012] Preferably, the adhesion promoter is at least one of pentaerythritol tetrakis(3-mercaptopropionate), 2,3-dithio(2-mercapto)-1-propanethiol, and 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol.

[0013] Preferably, the adhesion promoter is at least one of 2-hydroxyethyl methacrylate phosphate and alkyl acrylate phosphate.

[0014] Another object of the present invention is to provide a method for preparing the above-mentioned high-strength shock-resistant acrylic two-component structural adhesive, comprising the following steps: (1) Preparation of component A: Add the acrylate monomer into the reactor and stir it evenly at a speed of 800 rpm. Then add the elastomer and toughening agent in sequence and continue stirring until they are completely dissolved. After reducing the stirring speed to 400 rpm, add the stabilizer and stir evenly. When the temperature in the reactor is below 40°C, add the main accelerator, curing accelerator, adhesion accelerator and bonding accelerator and stir evenly. Then add the pigment and stir evenly. Degas under vacuum at -0.05 MPa for 3 minutes before discharging. (2) Preparation of component B: Add the acrylate monomer into the reactor and stir it evenly at a speed of 800 rpm. Add the elastomer and toughening agent and continue stirring until they are completely dissolved. Reduce the stirring speed to 400 rpm, add the stabilizer and stir evenly. When the temperature in the reactor is below 40°C, add the peroxide and stir evenly. Add the pigment and stir evenly. Degas under vacuum at -0.05 MPa for 3 minutes before discharging.

[0015] The reaction mechanism of the present invention is as follows: the toughening agent in the present invention improves the impact resistance and toughness of the high-strength, seismic-resistant two-component acrylic structural adhesive after curing, and reduces the risk of cracking; the curing accelerator and the adhesion promoter work synergistically to improve the adhesion to the metal surface; the adhesion promoter is introduced innovatively, and the thiol group (-SH) in the adhesion promoter and the double bond of the acrylate in the structural adhesive form a three-dimensional cross-linked network through a chemical reaction, which significantly improves the curing performance of the structural adhesive and greatly improves the bonding strength of the two-component acrylic structural adhesive product to red copper, with the bonding strength to red copper being greater than 23 MPa; the phosphate group in the adhesion promoter molecule can chemically react with oxides or hydroxyl groups on the surface of materials such as metals and ceramics to form a stable phosphate or ester bond structure, thereby enhancing the interfacial bonding strength.

[0016] Beneficial effects of the present invention: (1) Significantly improved bonding strength: The present invention introduces an adhesion promoter. The mercapto group in the adhesion promoter forms a three-dimensional cross-linked network with the double bond of the acrylate. Combined with the interfacial chemical bonding effect of the adhesion promoter, the shear strength of the copper bonding exceeds 23 MPa, the strength of the bonding steel substrate can reach more than 29 MPa, and the strength of the bonding aluminum sheet can reach more than 16 MPa.

[0017] (2) Excellent seismic performance: The synergistic effect of the toughening agent and the elastomer greatly improves the toughness of the adhesive layer, and the impact resistance is enhanced after curing. The steel bonding test piece using the product of the present invention can reach more than 15 times after a 1.5-meter free drop, and the aluminum bonding test piece can reach more than 50 times after a 1.5-meter free drop, which can meet the long-term stability requirements of high-frequency vibration scenarios such as high-speed rail and aerospace.

[0018] (3) The product of the present invention has wide applicability and high versatility: The product of the present invention has better bonding strength to various materials such as steel, aluminum, copper, and ABS than commercially available products, and it cures quickly at room temperature and has strong process adaptability. Therefore, the present invention has significant technical advantages and broad applications in the field of high-end industrial bonding. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0020] The toughening agent used in the present invention is solvent-based polyurethane in the form of particles.

[0021] Example 1: A high-strength, shock-resistant, two-component acrylic structural adhesive, comprising component A and component B. The components, in parts by weight, are as follows: Component A comprises: 65 parts of acrylate monomer; 22.5 parts of elastomer; 5.2 parts of toughening agent; 0.01 parts of stabilizer; 5 parts of main accelerator; 0.5 parts of curing accelerator; 0.5 parts of adhesion promoter; 1.3 parts adhesion promoter; Pigment 0.0002 parts; Component B includes: 65 parts of acrylate monomer; 24 parts of elastomer; 1.2 parts of stabilizer; 5 parts of peroxide; 4.8 parts of toughening agent; 0.0002 parts of pigment.

[0022] Table 1 shows the specific components of Example 1

[0023] Example 2: A high-strength, shock-resistant acrylic two-component structural adhesive, comprising component A and component B. The components, in parts by weight, are as follows: Component A includes: 70 parts of acrylate monomer; 20 parts of elastomer; 3.5 parts of toughening agent; 0.01 parts of stabilizer; 5 parts of main accelerator; 0.5 parts of curing accelerator; 0.5 parts of adhesion promoter; 0.5 parts of adhesion promoter; Pigment 0.0002 parts; Component B includes: 70 parts of acrylate monomer; 21 parts of elastomer; 1.2 parts of stabilizer; 5 parts of peroxide; 2.8 parts of toughening agent; 0.0002 parts of pigment.

[0024] Table 2 shows the specific components of Example 2

[0025] Example 3: A high-strength, shock-resistant acrylic two-component structural adhesive, comprising component A and component B. The components, in parts by weight, are as follows: Component A includes: 65.2 parts of acrylate monomer; 23 parts of elastomer; 4 parts of toughening agent; 0.01 parts of stabilizer; 5 parts of main accelerator; 0.5 parts of curing accelerator; 0.3 parts of adhesion promoter; 2 parts adhesion promoter; Pigment 0.0001 parts; Component B includes: 65 parts of acrylate monomer; 24 parts of elastomer; 1.2 parts of stabilizer; 5 parts of peroxide; 4.8 parts of toughening agent; 0.0001 parts of pigment.

[0026] Table 3 shows the specific components of Example 3

[0027] Comparative Example 1: An acrylic two-component structural adhesive includes component A and component B. The components are as follows in parts by weight.

[0028] Table 4 shows the specific components of Comparative Example 1

[0029] .

[0030] In order to illustrate the effect, no toughening agent and adhesion promoter were added in the A component of Comparative Example 1, and no toughening agent was added in the B component.

[0031] Comparative Example 2: An acrylate two-component structural adhesive including A component and B component, the components of each component are as follows in parts by weight.

[0032] Table 5 is the specific component situation of Comparative Example 2

[0033]

[0034] In order to illustrate the effect, no toughening agent was added in the A component and B component of Comparative Example 2.

[0035] Comparative Example 3: An acrylate two-component structural adhesive including A component and B component, the components of each component are as follows in parts by weight.

[0036] Table 6 is the component situation of Comparative Example 3

[0037]

[0038] In order to illustrate the effect, no adhesion promoter was added in the A component of Comparative Example 3.

[0039] The above examples and comparative examples are prepared by the following method (when there is no corresponding component in the comparative example, the amount is 0 parts by weight): (1) Preparation of A component: The acrylate monomer was put into the reaction kettle and stirred uniformly at a speed of 800 revolutions per minute, and then the elastomer and the toughening agent were added, and the stirring was continued until completely dissolved, and then the stirring speed was reduced to 400 revolutions per minute, and then the stabilizer was added, and stirred uniformly, and the temperature in the reaction kettle was below 40°C, and then the main accelerator, the curing accelerator, the adhesion promoter, and the pigment were added, and stirred uniformly, and then the material was discharged after vacuum degassing at -0.05 MPa for 3 minutes. (2) Preparation of B component: The acrylate monomer was put into the reaction kettle and stirred uniformly at a speed of 800 revolutions per minute, and then the elastomer and the toughening agent were added, and the stirring was continued until completely dissolved, and then the stirring speed was reduced to 400 revolutions per minute, and then the stabilizer was added, and stirred uniformly, and the temperature in the reaction kettle was below 40°C, and then the peroxide was added, and stirred uniformly, and then the pigment was added, and stirred uniformly, and then the material was discharged after vacuum degassing at -0.05 MPa for 3 minutes.

[0040] The A component and the B component of the acrylate structural adhesive prepared in the examples and the comparative examples were used according to the weight ratio of 1:1, and the performance was tested by the following tests.

[0041] The tensile shear strength was tested according to GB / T 7124-2008, and the bonding materials were 45# carbon steel (referred to as steel in the present invention), red copper, aluminum, and ABS.

[0042] Seismic performance test: Test specimens were prepared according to GB / T 7124-2008. The bonding materials were steel, aluminum, and copper. The specimens, which had been bonded and cured at room temperature for 24 hours, were dropped horizontally from a height of 1.5 meters onto a concrete floor. The 1.5-meter free-fall step was repeated until the bonded specimen broke at the bond. The number of drops was recorded.

[0043] Table 7 is the shear strength test results of the embodiments and comparative examples after bonding

[0044] As can be seen from the above table, the two-component acrylic structural adhesive described in the present invention achieves seismic resistance after bonding steel, aluminum, and copper materials; and has high bonding strength to copper, which can better meet the bonding needs of daily and industrial complex assembly processes and other working conditions with high vibration.

[0045] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the scope of protection of the present invention.

Claims

1. A high-strength, shock-resistant acrylic two-component structural adhesive, characterized by: It includes component A and component B, and the specific weight parts are as follows: Component A includes: 65-70 parts of acrylate monomer; 20-23 parts of elastomer; 3.5-5.2 parts of toughening agent; 0.01 parts of stabilizer; 5 parts of main accelerator; 0.5 parts of curing accelerator; Adhesion promoter 0.3-0.5 parts; Adhesion promoter 0.5-2 parts; Pigment 0-0.0002 parts; Component B includes: 65-70 parts of acrylate monomer; 21-24 parts of elastomer; 1.2 parts of stabilizer; 5 parts of peroxide; 2.8-4.8 parts of toughening agent; Pigment 0-0.0002 parts.

2. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The acrylate monomer is at least one of methyl methacrylate, isobornyl methacrylate, methacrylic acid, hydroxyethyl methacrylate, hydroxypropyl methacrylate, 1,3-butanediol dimethacrylate, 2-phenoxyethyl methacrylate, tetrahydrofuranyl methacrylate, ethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

3. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The elastomer is at least one of nitrile rubber, chloroprene rubber, chlorosulfonated polyethylene, ABS, and MBS.

4. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The toughening agent is solvent-based polyurethane.

5. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The stabilizer is at least one of hydroquinone, hydroquinone, naphthoquinone, 2,6-di-tert-butyl-p-methylphenol, and EDTA sodium salt.

6. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The primary accelerator is at least one of monoethylamine, diethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, tetramethylthiourea, and ethylenethiourea.

7. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The peroxide is at least one of cumene hydroperoxide, benzoyl peroxide, and dicumyl hydroperoxide; and the curing accelerator is at least one of sodium o-benzoylsulfonimide and acetylacetone metal salts.

8. The high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The adhesion promoter is at least one of pentaerythritol tetrakis(3-mercaptopropionate), 2,3-dithio(2-mercapto)-1-propanethiol, and 4-mercaptomethyl-3,6-dithia-1,8-octanedithiol.

9. The method for preparing a high-strength, shock-resistant acrylic two-component structural adhesive according to claim 1, characterized in that: The adhesion promoter is at least one of 2-hydroxyethyl methacrylate phosphate and alkyl acrylate phosphate.

10. A method for preparing a high-strength, shock-resistant acrylic two-component structural adhesive according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Preparation of component A: Add the acrylate monomer into the reactor and stir it evenly at a speed of 800 rpm. Then add the elastomer and toughening agent in sequence and continue stirring until they are completely dissolved. After reducing the stirring speed to 400 rpm, add the stabilizer and stir evenly. When the temperature in the reactor is below 40°C, add the main accelerator, curing accelerator, adhesion accelerator and bonding accelerator and stir evenly. Then add the pigment and stir evenly. Degas under vacuum at -0.05 MPa for 3 minutes before discharging. (2) Preparation of component B: Add the acrylate monomer into the reactor and stir it evenly at a speed of 800 rpm. Add the elastomer and toughening agent and continue stirring until they are completely dissolved. Reduce the stirring speed to 400 rpm, add the stabilizer and stir evenly. When the temperature in the reactor is below 40°C, add the peroxide and stir evenly. Add the pigment and stir evenly. Degas under vacuum at -0.05 MPa for 3 minutes before discharging.

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