Environment-friendly PMMA-based high-performance adhesive as well as preparation method and application thereof

Abstract

The invention discloses an environment-friendly PMMA (polymethyl methacrylate)-based high-performance adhesive as well as a preparation method and application thereof, and belongs to the technical field of adhesives. The adhesive is prepared by taking methyl methacrylate as a matrix and a multi-sulfydryl component and a diene component as cross-linking agents, uniformly mixing according to a ratio, and carrying out one-step cross-linking by adopting an environment-friendly ultraviolet curing process. The adhesive has both strength and toughness, and has strong anti-pressure capability and large deformation quantity; meanwhile, simple and mild adhesion conditions are achieved, and firm adhesion under the dry condition can be achieved without high temperature and pretreatment; and stable adhesion can still be maintained even in severe environments such as humid and low-temperature environments. Due to the existence of ester groups in the components, the adhesive can be quickly degraded at room temperature in a strong alkali environment.

Description

Technical Field

[0001] The present invention belongs to the technical field of adhesives, and particularly relates to a class of environmentally friendly PMMA-based high-performance adhesives, a preparation method thereof, and applications thereof. Background Art

[0002] An adhesive refers to a substance that connects two or more materials through its own cohesive force and interfacial adhesion to the substrate. Compared with early natural adhesives such as bone glue and fish glue, cross-linked adhesives have better adhesion ability and rubbing fastness.

[0003] Currently, commonly used adhesives are mostly petroleum-based products, such as epoxy adhesives, polyurethane adhesives, etc. They are not only non-renewable in source, but also volatile toxic substances will be released during synthesis and use, which have an adverse impact on the human body and the environment. Moreover, epoxy adhesives are brittle and prone to cracks under stress, resulting in bonding failure; while polyurethane adhesives require sufficient surface treatment of the substrate to achieve better adhesion.

[0004] Most adhesives can maintain good adhesion strength under dry conditions. However, in harsh environments such as humidity and low temperature, adhesives will be affected by the environment, and the adhesion strength will decrease to varying degrees or even bonding failure will occur. Therefore, preparing a high-performance adhesive with good environmental protection, high adhesion strength, easy operation and can be used in harsh environments is an important problem faced in practical applications.

[0005] However, the existing technology still has the following bottlenecks:

[0006] 1. Conflict between environmental protection and performance: Although bio-based materials (such as cellulose, starch) have been tried to replace petroleum-based raw materials, their adhesion strength (usually ≤ 1 MPa) and weather resistance are much lower than those of traditional adhesives;

[0007] 2. Insufficient adaptability to harsh environments: The adhesion strength of existing environmentally friendly adhesives generally drops by more than 80% under humid or low temperature (such as below -20 °C) conditions, and they cannot withstand dynamic loads (such as thermal expansion and contraction deformation of metals);

[0008] 3. Contradiction between degradability and stability: Introducing degradable components (such as ester bonds) often leads to premature decomposition of the material in a humid environment (such as degradation > 50% within 48 h), which cannot meet the long-term use requirements;

[0009] 4. Limitations of the photocuring process: Although ultraviolet curable adhesives can reduce the use of solvents, existing formulations rely on a high proportion of acrylate monomers (> 50 wt%), resulting in high brittleness (elongation at break < 20%), and the residue of photoinitiators will reduce biocompatibility.

[0010] The above problems indicate that the prior art cannot achieve the coordinated optimization of environmental friendliness, environmental adaptability, degradability, and mechanical properties by simply replacing components or adjusting process parameters, nor does it suggest solutions to the above contradictions through specific ratio designs of magnolol and mercapto crosslinking agents, screening of ultraviolet initiators, etc. Summary of the Invention

[0011] In view of the problems existing in the prior art, the present invention provides a class of environmentally friendly PMMA-based high-performance adhesives and their preparation methods.

[0012] The first aspect of the present invention discloses a preparation method of an environmentally friendly PMMA-based high-performance adhesive. The adhesive is prepared by a thiol-ene click reaction initiated by light from methyl methacrylate, diene component A, and polyfunctional mercapto component B. Among them, methyl methacrylate is used as the matrix, and polyfunctional mercapto component B and diene component A are used as crosslinking agents for copolymerization. The mass ratio of each component is diene component A: polyfunctional mercapto component B: methyl methacrylate = 0.5 - 1:1:0.1 - 0.5. The dosage of the photoinitiator is 1.5 - 2.5% of the total mass, and the solvent volume is 0.5 - 1.5 ml / g of the mixed system. Considering the stability of the comprehensive crosslinked structure and the functionality of methyl methacrylate, the adhesive realizes rapid bonding under mild conditions and functional characteristics such as water resistance and cold resistance.

[0013] For the above-mentioned technical solution, further preferably, a preparation method of an environmentally friendly PMMA-based high-performance adhesive includes the following steps:

[0014] Add methyl methacrylate, diene component A, polyfunctional mercapto component B, and solvent into a reactor, stir at room temperature, and mix evenly to obtain a first solution; add an initiator into the first solution, stir at room temperature, and mix evenly to obtain a second solution; spread the second solution on a mold (for example, an inert material mold such as polytetrafluoroethylene, silica gel, polyethylene, etc. that provides a non-stick surface for demolding), and expose it to ultraviolet light with a wavelength of 320 - 400 nm and a light intensity of 10 - 100 mW / cm 2 for one hour, then place it in a vacuum oven at 50 - 80 °C and -0.08 MPa for drying for 1 - 3 h. After exposing it to ultraviolet light for one hour, place it in a vacuum oven for drying to remove the solvent, and the required PMMA-based adhesive is obtained.

[0015] For the above-mentioned technical solution, further preferably, the diene component A is magnolol.

[0016] For the above-mentioned technical solution, further preferably, the polyfunctional mercapto component B is pentaerythritol tetra(3-mercaptopropionate), trimethylolpropane tris(3-mercaptopropionate).

[0017] For the technical solution described above, more preferably, the solvent is a polar organic solvent; the addition amount of the solvent is 0.5 - 1.5 ml per gram of the total solid mass, and the total solid mass is the sum of the masses of methyl methacrylate, diene component A, multi-mercapto component B, and photoinitiator.

[0018] For the technical solution described above, more preferably, the solvent is tetrahydrofuran, DMF.

[0019] For the technical solution described above, more preferably, in the preparation raw materials: the feeding molar ratio of the double bonds in diene component A to the mercapto groups in multi-mercapto component B is 0.6 - 0.9:1, and the feeding molar proportion of the double bonds in methyl methacrylate to the total mercapto groups is 10 - 40%; the feeding amount of the initiator is 1.5 - 2.5 wt% of the total mass of diene component A, multi-mercapto component B, and methyl methacrylate.

[0020] For the technical solution described above, more preferably, the initiator is at least one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, benzoin dimethyl ether, and benzophenone.

[0021] For the technical solution described above, more preferably, the amount of the initiator used is 0.03 - 0.05 g / g of the mixed system.

[0022] The second aspect of the present invention is to protect a class of environmentally friendly PMMA-based high-performance adhesives prepared by the above method. This adhesive has environmental friendliness, excellent weather resistance, multi-substrate compatibility, and characteristics of rapid curing and pre-treatment-free, realizing multi-level application coverage. At this time, the adhesion strengths of the adhesive at dry, humid, and -196 °C are 1.6 - 6.2 MPa, 0.35 - 5.7 MPa, and 1.5 - 4.3 MPa respectively, and it can be completely degraded within 35 min in 1M NaOH solution.

[0023] The third aspect of the present invention lies in protecting the application of the environment-friendly PMMA-based high-performance adhesive, which achieves multi-level application coverage through four core technical advantages: at the macroscopic level, its environmental friendliness (UV curing process, rapid degradability) empowers the green manufacturing system and promotes the upgrading of strategic industries such as biodegradable medical devices and carbon-neutral packaging; at the mesoscopic industry dimension, the excellent weather resistance (wet environment strength retention rate ≥ 50%, adhesion force of 1.75 MPa still maintained at -196 °C) breaks through the technical bottlenecks of extreme environment industries and supports scenarios such as polar equipment, deep-sea engineering, and outdoor building sealing; in terms of cross-industry versatility, the multi-substrate compatibility (dry state strength of metal / wood reaches 1.62 - 6.21 MPa) breaks through the material adaptation barriers in fields such as automotive lightweight bonding, ship and warship repair, and environmental protection building material splicing; and at the microscopic operation level, the rapid curing (1h UV forming) and pre-treatment-free characteristics significantly improve the production line efficiency, enabling the large-scale implementation of high-frequency and high-timeliness requirements such as instant repair of consumer products and on-site water leakage plugging in industry, forming a full-chain technical penetration from industrial innovation to terminal application.

[0024] The beneficial effects of the present invention are as follows:

[0025] The present invention uses methyl methacrylate as the matrix, and a multi-mercapto component (such as pentaerythritol tetra-(3-mercaptopropionate)) and a diene component as crosslinking agents. After being uniformly mixed in a specific ratio (such as in Example 4, magnolol: mercapto crosslinking agent: methyl methacrylate = 0.6541:1:0.3278), a class of environmentally friendly PMMA-based high-performance adhesives is designed and synthesized by using an environmentally friendly ultraviolet curing process. Experimental data show (see Tables 1-3) that the obtained adhesives exhibit significant and stable adhesion strengths under dry, humid, extremely low temperature (-196 °C) and multi-substrate (wood, metal, etc.) conditions (such as the dry / wet strengths of Example 4 on an aluminum substrate are 2.41 MPa and 1.20 MPa respectively, and still maintain 1.75 MPa at -196 °C). And through the synergistic effect of magnolol and the mercapto crosslinking agent, its comprehensive performance far exceeds that of conventional PMMA adhesives (such as the dry strength of Comparative Example 1 decreased to ≤1 MPa after removing magnolol). The adhesive prepared by the present invention has both strength and toughness, has strong compressive capacity and large deformation, and is not easily damaged by external forces. And this adhesive has simple and mild adhesion conditions, and can achieve firm adhesion under dry conditions without high temperature and pretreatment; even under harsh environments such as humidity and low temperature, it can still maintain stable adhesion (see Tables 2-3, the wet and low-temperature adhesion strengths only decrease by about 20-50%, while conventional adhesives usually decrease by more than 80%). In addition, through the optimization of the type of photoinitiator (such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide compared with benzoin dimethyl ether, Examples 4 and 9 show that the dry strength is increased by about 20%) and the regulation of the solvent ratio (the volume of tetrahydrofuran is reduced to 0.5 ml and still ensures uniform curing), the present invention breaks through the balance problem among environmental adaptability, durability and environmental protection of traditional materials. The present invention is prepared by one-step crosslinking through an environmentally friendly ultraviolet curing process, and can be rapidly degraded at room temperature after being discarded (such as Example 4 is completely degraded within 35 minutes in 1M NaOH solution), effectively reducing the adverse effects on the human body and the environment during the synthesis and use process. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the adhesion process of the present invention;

[0027] Figure 2 are the stress-strain curves of Examples 1-4 of the present invention;

[0028] Figure 3 are the dry and wet adhesion strengths of Example 4 of the present invention on various substrates;

[0029] Figure 4 is the low-temperature adhesion strength of Example 4 of the present invention on an aluminum substrate;

[0030] Figure 5 is the degradation process of Example 4 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the solutions of the present invention will be further described below. However, the embodiments of the present invention are not limited thereto, and any combination can be made among various different embodiments of the present invention. Without departing from the idea of the present invention, it should also be regarded as the content disclosed by the present invention.

[0032] The preferred embodiments of the present invention will be described in detail below in conjunction with examples. However, the following examples are only used to illustrate the present invention in detail and do not limit the scope of the present invention in any way. All other examples obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0033] The materials, reagents, etc. used in the following examples are all commercially available as ordinary ones unless otherwise specified. The test methods used in the following examples are all conventional methods unless otherwise specified.

[0034] In the following examples, lap shear tests were carried out with reference to ASTM D1002, and the tensile rate was 5 mm / min. When the mass of the adhesive decreased to less than 5% of the initial mass, it was considered to be completely degraded.

[0035] "Room temperature" refers to 20 - 25 °C, and "vacuum drying" refers to drying under the conditions of -0.08 MPa and 60 °C.

[0036] Example 1

[0037] 0.9811 g of magnolol, 1 g of pentaerythritol tetra(3-mercaptopropionate), 0.0819 g of methyl methacrylate and 1 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0413 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0038] The second solution was coated on a polytetrafluoroethylene mold, exposed to ultraviolet light for one hour, and then placed in a vacuum oven to dry to remove the excess solvent, obtaining PMMA-based adhesive sample 1.

[0039] Example 2

[0040] 0.8721 g of magnolol, 1 g of pentaerythritol tetra(3-mercaptopropionate), 0.1639 g of methyl methacrylate and 1 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0407 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0041] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and the excess solvent was removed to obtain PMMA-based adhesive sample 2.

[0042] Example 3

[0043] 0.7631 g of magnolol, 1 g of pentaerythritol tetra(3-mercaptopropionate), 0.2459 g of methyl methacrylate and 0.75 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0402 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0044] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and the excess solvent was removed to obtain PMMA-based adhesive sample 3.

[0045] Example 4

[0046] 0.6541 g of magnolol, 1 g of pentaerythritol tetra(3-mercaptopropionate), 0.3278 g of methyl methacrylate and 0.5 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0396 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0047] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and the excess solvent was removed to obtain PMMA-based adhesive sample 4.

[0048] Example 5

[0049] 0.9021 g of magnolol, 1 g of trimethylolpropane tris(3-mercaptopropionate), 0.0754 g of methyl methacrylate and 1 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0395 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0050] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and the excess solvent was removed to obtain PMMA-based adhesive sample 5.

[0051] Example 6

[0052] Add 0.8019 g of magnolol, 1 g of trimethylolpropane tris(3-mercaptopropionate), 0.1507 g of methyl methacrylate, and 1 ml of tetrahydrofuran into a reaction flask, stir evenly at room temperature to obtain a first solution. Add 0.0391 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide into the first solution, and stir evenly at room temperature to obtain a second solution.

[0053] Coat the second solution on a polytetrafluoroethylene mold, expose it to ultraviolet light for one hour, then place it in a vacuum oven to dry and remove the excess solvent to obtain PMMA-based adhesive sample 6.

[0054] Example 7

[0055] Add 0.7017 g of magnolol, 1 g of trimethylolpropane tris(3-mercaptopropionate), 0.2261 g of methyl methacrylate, and 0.75 ml of tetrahydrofuran into a reaction flask, stir evenly at room temperature to obtain a first solution. Add 0.0386 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide into the first solution, and stir evenly at room temperature to obtain a second solution.

[0056] Coat the second solution on a polytetrafluoroethylene mold, expose it to ultraviolet light for one hour, then place it in a vacuum oven to dry and remove the excess solvent to obtain PMMA-based adhesive sample 7.

[0057] Example 8

[0058] Add 0.6014 g of magnolol, 1 g of trimethylolpropane tris(3-mercaptopropionate), 0.3015 g of methyl methacrylate, and 0.5 ml of tetrahydrofuran into a reaction flask, stir evenly at room temperature to obtain a first solution. Add 0.0381 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide into the first solution, and stir evenly at room temperature to obtain a second solution.

[0059] Coat the second solution on a polytetrafluoroethylene mold, expose it to ultraviolet light for one hour, then place it in a vacuum oven to dry and remove the excess solvent to obtain PMMA-based adhesive sample 8.

[0060] Example 9

[0061] Add 0.6541 g of magnolol, 1 g of pentaerythritol tetra(3-mercaptopropionate), 0.3278 g of methyl methacrylate, and 0.5 ml of tetrahydrofuran into a reaction flask, stir evenly at room temperature to obtain a first solution. Add 0.0396 g of benzoin dimethyl ether into the first solution, and stir evenly at room temperature to obtain a second solution.

[0062] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and remove the excess solvent, obtaining PMMA-based adhesive sample 9.

[0063] Example 10

[0064] 0.6541 g of magnolol, 1 g of pentaerythritol tetra-(3-mercaptopropionate), 0.3278 g of methyl methacrylate and 0.5 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0396 g of benzophenone was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0065] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and remove the excess solvent, obtaining PMMA-based adhesive sample 10.

[0066] Example 11

[0067] 0.6541 g of magnolol, 1 g of pentaerythritol tetra-(3-mercaptopropionate), 0.3278 g of methyl methacrylate and 0.5 ml of DMF were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0396 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0068] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and remove the excess solvent, obtaining PMMA-based adhesive sample 11.

[0069] Comparative Example 1:

[0070] 0.7742 g of magnolol, 1 g of decanedithiol, 0.3880 g of methyl methacrylate and 0.5 ml of tetrahydrofuran were added to a reaction flask and stirred evenly at room temperature to obtain a first solution. 0.0432 g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide was added to the first solution and stirred evenly at room temperature to obtain a second solution.

[0071] The second solution was applied to a polytetrafluoroethylene mold. After being exposed to ultraviolet light for one hour, it was placed in a vacuum oven to dry and remove the excess solvent, obtaining comparative sample 1.

[0072] Comparative Example 2:

[0073] Add 0.5507 g of 1,6 - hexanediol diacrylate, 1 g of pentaerythritol tetra(3 - mercaptopropionate), 0.3278 g of methyl methacrylate and 0.5 ml of tetrahydrofuran to a reaction flask, stir evenly at room temperature to obtain a first solution. Add 0.0376 g of 2,4,6 - trimethylbenzoyl - diphenylphosphine oxide to the first solution, stir evenly at room temperature to obtain a second solution.

[0074] Coat the second solution on a polytetrafluoroethylene mold, expose it to ultraviolet light for one hour, then place it in a vacuum oven to dry and remove the excess solvent to obtain Comparative Example Sample 2.

[0075] Effect Example 1: Adhesion Experiment of PMMA - based Adhesive

[0076] Select wood, aluminum, aluminum alloy and stainless steel as substrates to conduct a lap - shear test to measure the bonding strength of the PMMA - based adhesive.

[0077] Bonding method: Cut adhesive samples with a bonding area size of (12.5 mm × 25 mm), overlap the ends of two substrates with the adhesive respectively, fix them with a spring clip, place them in an oven at 80 °C for 20 min, and then conduct a lap - shear test after cooling for 24 h. Finally, calculate the dry adhesion strength through a formula. After the bonded samples are soaked in hot water at 63 °C for 3 h, the measured adhesion strength is used as the wet adhesion strength. The specific results are shown in the table:

[0078] Table 1 Dry Bonding Strength of PMMA - based Adhesive on Different Substrates (Unit: MPa)

[0079]

[0080]

[0081] Table 2 Wet Bonding Strength of PMMA - based Adhesive on Different Substrates (Unit: MPa)

[0082] wood aluminum aluminum alloy stainless steel Sample 1 1.3527 4.3029 5.7025 5.2033 Sample 2 1.0926 4.6751 5.2906 4.1170 Sample 3 0.7586 2.2506 3.3359 2.3079 Sample 4 0.39863 1.2017 2.13137 1.64103 Sample 5 1.2013 4.3517 5.3097 4.7086 Sample 6 1.0509 3.5876 4.8217 3.7963 Sample 7 0.6576 2.7639 3.1195 1.7065 Sample 8 0.3634 1.9753 1.8893 1.3597 Sample 9 0.3741 1.3506 2.0916 1.5428 Sample 10 0.3540 1.7329 2.1329 1.5097 Sample 11 0.1097 0.9351 1.7936 1.3359 Comparative Example 2 / 0.3095 0.4439 0.3706

[0083] Select aluminum as the substrate to conduct an adhesion experiment at low temperature. Expose it in different low - temperature environments for 24 h, and measure its adhesion strength as the low - temperature adhesion strength. The specific results are shown in the following table:

[0084] Table 3 Low - temperature Bonding Strength of PMMA - based Adhesive on Al (Unit: MPa)

[0085] 25℃ 0℃ -18℃ -196℃ Sample 1 6.2089 6.1097 5.8863 4.3462 Sample 2 5.7683 5.3621 5.3546 4.0955 Sample 3 3.7564 3.7330 3.3321 2.5919 Sample 4 2.4098 2.3497 2.08905 1.75232 Sample 5 5.6830 5.6587 5.2589 3.8644 Sample 6 4.9837 4.7095 4.4097 3.3655 Sample 7 3.5396 3.3098 3.0575 2.4246 Sample 8 2.2576 2.1359 1.7651 `1.5875 Sample 9 2.1285 2.0927 1.6597 1.4900 Sample 10 2.3516 2.2538 1.8059 1.7167 Sample 11 2.0658 2.0163 1.3379 1.2536 Comparative Example 2 0.1057 0.4097 0.5065 0.3306

[0086] Effect Example 2: Degradation Study of PMMA - based Adhesive

[0087] Taking the adhesive synthesized in Example 4 as an example, 20 mg of the sample was completely immersed in 1 M NaOH solution at room temperature, and the change in its mass over time was observed. As can be seen from the figure, after 35 min, the adhesive was completely degraded and disappeared.

[0088] In summary, through the systematic experimental data of Examples 1-10, the present invention fully demonstrates that the prepared PMMA-based adhesive exhibits significant and stable adhesion strength in dry / wet environments, extreme low temperature (-196 °C), and multiple substrates (wood, metal, etc.) (for example, the dry / wet strengths of Example 4 on aluminum substrate are 2.41 MPa and 1.20 MPa respectively, and still maintain 1.75 MPa at -196 °C), and at the same time has the characteristics of rapid degradation (completely degraded in alkaline environment within 35 minutes). The synergistic improvement of these properties stems from the specific proportion design of magnolol and mercapto crosslinker in the formulation, the selection of photoinitiator type (such as the performance difference between 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and benzoin dimethyl ether), and the optimization of solvent proportion. Its comprehensive effect exceeds the reasonable expectation of those skilled in the art for conventional PMMA-based adhesives, indicating that the present invention breaks through the balance problem among environmental adaptability, durability, and environmental protection of traditional materials through the synergistic effect among components.

[0089] It should be understood that the above embodiments are only for more clearly illustrating the technical solutions of the present invention, rather than limiting the scope of its protection. Those of ordinary skill in the art can make various modifications and variations to the above embodiments without departing from the spirit and basic principles of the present invention, but these modifications and variations still fall within the protection scope of the claims of the present invention and their equivalent replacements. The protection scope of the present invention shall be subject to the appended claims, rather than being limited to the specific details of the above embodiments.

Claims

1. A class of environmentally friendly PMMA-based high-performance adhesives, their preparation methods and applications, characterized in that: The environmentally friendly PMMA-based high-performance adhesive is prepared by a thiol-ene click reaction of methyl methacrylate, diene component A and poly-thiol component B; wherein, component B is used to provide the thiol groups required for the thiol-ene click reaction; methyl methacrylate and component A are used to provide the double bonds required for the thiol-ene click reaction; the mass ratio of the diene component A: poly-thiol component B: methyl methacrylate is 0.5-1:1:0.1-0.

5.

2. The preparation method according to claim 1, characterized in that, It includes the following steps: First, methyl methacrylate, diene component A, poly-thiol component B and a solvent are mixed evenly to obtain a first solution; Secondly, an initiator is added to the first solution, and stirred at room temperature. After mixing evenly, a second solution is obtained; Finally, the second solution is coated on a mold, exposed to ultraviolet light, dried, and the solvent is removed to obtain the product.

3. The preparation method according to claim 1, wherein In its preparation raw materials: the feeding molar ratio of the diene component A and the poly-thiol component B is 0.6-0.9:1, and the feeding molar ratio of the double bonds in methyl methacrylate accounts for 10-40% of the total thiols; the feeding amount of the initiator is 1.5-2.5 wt% of the total mass of the diene component A, the poly-thiol component B and methyl methacrylate; the total solid mass is the sum of the masses of methyl methacrylate, the diene component A, the poly-thiol component B and the photoinitiator.

4. The preparation method according to claim 1, characterized in that, It is characterized in that The diene component A is magnolol.

5. The preparation method according to claim 1, characterized in that The poly-thiol component B is at least one of tetra-(3-mercaptoallyl)pentaerythritol ester and trimethylolpropane tris(3-mercaptopropionate).

6. The preparation method according to claim 1, characterized in that The solvent is a polar organic solvent; the ratio of the total solid mass to the solvent volume is 1:(0.5-1.5) g / ml, and the total solid mass is the sum of the masses of methyl methacrylate, the diene component A, the poly-thiol component B and the photoinitiator.

7. The preparation method according to claim 1, wherein The solvent is at least one of tetrahydrofuran and DMF.

8. The preparation method according to claim 1, characterized in that, The initiator is at least one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, benzoin dimethyl ether and benzophenone.

9. A class of environmentally friendly PMMA-based high-performance adhesives prepared by the method according to claim 1.

10. An application of the environmentally friendly PMMA-based high-performance adhesive prepared by the method according to claim 9 in the fields of automotive lightweight, ships and warships, and environmental protection building materials.

Images