High-temperature-resistant epoxy AB adhesive and preparation method thereof

Abstract

The application relates to the technical field of adhesives, and discloses a high-temperature-resistant epoxy AB adhesive and a preparation method thereof.The high-temperature-resistant epoxy AB adhesive comprises an A component and a B component; the A component comprises the following raw materials: bisphenol A type epoxy resin, an ultraviolet absorber, a defoaming agent, anti-aging oxidized graphene and deionized water; and the B component comprises the following raw materials: acid anhydride silicon oil and deionized water.The anti-aging oxidized graphene and the acid anhydride silicon oil are prepared and used in the preparation process of the epoxy AB adhesive, so that the prepared epoxy AB adhesive has excellent mechanical properties, high-temperature resistance and anti-aging performance, can stably play a bonding role for a long time in a high-temperature environment, does not stick during use, does not affect the use effect, is not prone to aging and cracking, can meet the use requirements in multiple fields, and has a long service life.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, specifically to a high-temperature resistant epoxy AB adhesive and its preparation method. Background Technology

[0002] Adhesives, as an indispensable chemical material in modern industry and daily life, play a vital role in promoting tight connections between objects, simplifying assembly processes, and improving production efficiency due to their unique adhesive properties. Among the many types of adhesives, epoxy resin is widely used in adhesive preparation due to its excellent processing performance and good bonding ability. Therefore, epoxy resin adhesives have become one of the most widely used adhesives. However, ordinary epoxy resin adhesives have limited high-temperature resistance, weak mechanical properties and anti-aging ability, making it difficult to meet the needs of use in various environments. Therefore, how to improve the performance of epoxy resin adhesives has become an important research direction.

[0003] Patent CN114591709B discloses a high-toughness epoxy resin adhesive and its preparation method. This epoxy resin adhesive uses cashew phenol-modified methyltetrahydrophthalic anhydride as a curing agent. The aromatic compound characteristics of the benzene ring structure of cashew phenol and the flexibility and self-drying properties of its long-chain hydrocarbon structure result in an epoxy resin adhesive with excellent high-temperature resistance and toughness, enabling its use at high temperatures and effectively overcoming cracking caused by curing shrinkage and temperature rise changes. However, this patent does not improve the anti-aging ability of the epoxy resin adhesive, which may lead to a decrease in bonding strength due to aging during long-term use, seriously affecting the service life of the epoxy resin adhesive. Summary of the Invention

[0004] The purpose of this invention is to provide a high-temperature resistant epoxy AB adhesive and its preparation method, which solves the following technical problems: (1) Ordinary epoxy AB adhesive has general high-temperature resistance and is prone to sticking in high-temperature environments, which affects the performance of use; (2) Ordinary epoxy AB adhesive is prone to aging and is prone to cracking and peeling after long-term use, which affects its service life.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A high-temperature resistant epoxy AB adhesive includes component A and component B; component A includes the following raw materials in parts by weight: 60-80 parts bisphenol A type epoxy resin, 1-2 parts ultraviolet absorber, 2-3 parts defoamer, 6-8 parts anti-aging graphene oxide, and 120-150 parts deionized water; component B includes the following raw materials in parts by weight: 20-30 parts anhydride silicone oil and 50-80 parts deionized water.

[0007] Furthermore, the ultraviolet absorber is any one of ultraviolet absorber UV-3030, ultraviolet absorber UV-384, and ultraviolet absorber UV-1130; the defoamer is any one of polyethylene oxide alcohol, dimethyl silicone oil, and polyethylene oxide.

[0008] Furthermore, the preparation method of the anti-aging graphene oxide includes the following steps:

[0009] (1) Add flake graphite powder to concentrated sulfuric acid, place in an ice bath at 0-4℃, add sodium nitrate and potassium permanganate, stir for 18-24h, add deionized water, cool to room temperature and add hydrogen peroxide solution with a concentration of 1-2mol / L. After the solution changes color, pour out the solution and filter it. Wash with hydrogen chloride solution with a mass fraction of 5-6% and deionized water in turn. Test the supernatant with barium chloride solution with a mass fraction of 2-3mol / L. After no precipitate is produced, dry the product to obtain graphene oxide.

[0010] (2) Place graphene oxide in N,N-dimethylformamide, ultrasonically disperse for 15-20 min, add rhein and catalyst, heat to 65-75℃ and react for 6-8 h, filter, wash and vacuum dry to obtain anti-aging graphene oxide.

[0011] Using the above technical solution, graphene oxide is prepared using the Hummers method. Then, under the action of a catalyst, the carboxyl groups in the rhein structure undergo a ring-opening reaction with the epoxy groups on the surface of the graphene oxide, yielding anti-aging graphene oxide. This anti-aging graphene oxide, using graphene oxide as the matrix material, possesses excellent mechanical strength and can significantly enhance the mechanical properties of epoxy AB adhesives. Furthermore, the matrix has a unique layered structure that acts as a barrier, preventing heat transfer and resisting thermal oxidative degradation, thereby effectively improving the high-temperature resistance of epoxy AB adhesives. The rhein coating on its surface... Acids can enhance the antioxidant capacity of epoxy AB adhesives and are chemically bonded to the surface of graphene oxide. This not only protects rhein to a certain extent but also effectively prevents the precipitation of small-molecule rhein during practical use, enabling it to exert long-lasting anti-aging capabilities. Furthermore, the anti-aging graphene oxide prepared through the grafting reaction between graphene oxide and rhein has multiple active hydroxyl groups on its surface, which can participate in the curing reaction of the epoxy adhesive matrix, fully enhancing the dispersibility of the anti-aging graphene oxide in the matrix material and enabling it to better exert its anti-aging effect.

[0012] Further, in step (2), the catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, and tetrabutylammonium hydroxide.

[0013] Furthermore, the preparation method of the anhydride-modified silicone oil includes the following steps:

[0014] S1: Mix toluene with zinc chloride, add terminal epoxy silicone oil and 2-adamantane alcohol, heat to 70-75℃ and react for 5-8 hours, collect the product after vacuum distillation to obtain adamantyl silicone oil;

[0015] S2: Mix xylene with potassium carbonate, add adamantyl silicone oil and 4-bromo-1,8-naphthalenedicarboxylic anhydride, heat to react, collect the product after vacuum distillation, and obtain anhydride-modified silicone oil.

[0016] Through the above technical solution, under the action of zinc chloride, the epoxy groups in the terminal epoxy silicone oil structure undergo a ring-opening reaction with the hydroxyl groups in the 2-adamantane alcohol structure to obtain adamantyl silicone oil containing hydroxyl groups. Then, under the action of potassium carbonate, the hydroxyl groups in the adamantyl silicone oil structure undergo a substitution reaction with the active bromine in the 4-bromo-1,8-naphthalenedicarboxylic anhydride structure to obtain anhydride-modified silicone oil. This anhydride-modified silicone oil structure has anhydride groups at both ends and can be used as an epoxy adhesive curing agent. The silicone oil segments in its structure contain a large number of silicon-oxygen bonds, which can produce a synergistic effect with the adamantane structure and naphthalene ring in its structure, jointly enhancing the high-temperature resistance of epoxy AB adhesive, making it stable in high-temperature environments, and preventing the adhesive from becoming sticky due to high temperatures, thus affecting the adhesive's bonding strength. This allows the prepared epoxy AB adhesive to be used for a long time, is not easy to fall off, and has a long service life.

[0017] Furthermore, in step S1, the viscosity of the terminal epoxy silicone oil is 220-300 cs.

[0018] Furthermore, in step S2, the temperature of the heating reaction is 55-65°C, and the time is 3-5 hours.

[0019] A method for preparing a high-temperature resistant epoxy AB adhesive includes the following steps:

[0020] Step 1: Mix bisphenol A type epoxy resin, ultraviolet absorber, defoamer, anti-aging graphene oxide and deionized water, and stir for 1.5-2.5 hours to obtain epoxy adhesive component A.

[0021] Step 2: Place the anhydride-modified silicone oil in deionized water and stir for 2-3 hours to obtain epoxy resin component B.

[0022] Furthermore, in step one, the stirring rate is 150-160 r / min.

[0023] Furthermore, in step two, the stirring rate is 120-130 r / min.

[0024] The beneficial effects of this invention are:

[0025] This invention incorporates anti-aging graphene oxide and anhydride silicone oil into the preparation process of epoxy AB adhesive, resulting in epoxy AB adhesive with excellent mechanical properties, high temperature resistance, and anti-aging properties. It can maintain stable bonding performance for a long time in high-temperature environments, does not become sticky during use, thus not affecting the performance, and is not prone to aging and cracking. It can meet the application requirements of multiple fields and has a long service life.

[0026] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 The UV spectra of the adamantyl alkyl silicone oil and the anhydride silicone oil of the present invention are shown below.

[0029] Figure 2 This is a sedimentation rate diagram of graphene oxide and anti-aging graphene oxide in a dispersant according to the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] The preparation methods of anti-aging graphene oxide and anhydride-modified silicone oil in the following embodiments and comparative examples of the present invention are as follows:

[0032] I. Preparation of Anti-aging Graphene Oxide

[0033] (1) Add 2g of flake graphite powder to 70ml of concentrated sulfuric acid, place in an ice bath at 0℃, add 1.2g of sodium nitrate and 15g of potassium permanganate, stir for 18h, add 120ml of deionized water; cool to room temperature and add 8ml of 1mol / L hydrogen peroxide solution. After the solution changes color, pour out the solution and filter it. Wash with 5% hydrogen chloride solution and deionized water in sequence. Test the supernatant with 2mol / L barium chloride solution. After no precipitate is produced, dry the product to obtain graphene oxide.

[0034] (2) 2.8g of graphene oxide was placed in 100ml of N,N-dimethylformamide and ultrasonically dispersed for 15min. Then, 3g of rhein and 0.05g of tetrabutylammonium bromide were added, and the mixture was heated to 65℃ and reacted for 6h. After filtration, washing and vacuum drying, anti-aging graphene oxide was obtained.

[0035] 2g of graphene oxide and 2g of anti-aging graphene oxide were ultrasonically dispersed in 150ml of toluene for 30min, followed by a sedimentation test. Figure 2 It can be seen that graphene oxide settles quickly, reaching sedimentation equilibrium within 2.5 hours, while anti-aging graphene oxide settles slowly, reaching sedimentation equilibrium within 8 hours. This is because graphene oxide has poor dispersibility in toluene and is prone to agglomeration, resulting in a fast sedimentation rate. However, anti-aging graphene oxide modified with rhein has enhanced dispersibility and is less prone to agglomeration, thus its sedimentation rate is slower.

[0036] In this scheme, under the action of tetrabutylammonium bromide, the epoxy groups in graphene oxide and the carboxyl groups in rhein undergo a ring-opening reaction, grafting rhein with antioxidant properties onto the surface of graphene oxide. Even during long-term use of epoxy AB adhesive, small-molecule rhein will not easily precipitate out, and can continuously exert its antioxidant effect, thereby improving the service life of epoxy AB adhesive.

[0037] II. Preparation of anhydride-modified silicone oil

[0038] S1: Mix 80 ml of toluene with 0.2 g of zinc chloride, add 3 g of terminal epoxy silicone oil with a viscosity of 220 cs and 2.6 g of 2-adamantane alcohol, heat to 70 °C and react for 5 h, collect the product after vacuum distillation to obtain adamantyl silicone oil;

[0039] S2: Mix 100 ml of xylene with 0.3 g of potassium carbonate, add 3.4 g of adamantyl silicone oil and 3 g of 4-bromo-1,8-naphthalenedicarboxylic anhydride, heat to 55 °C and react for 3 h, collect the product after vacuum distillation to obtain anhydride-modified silicone oil.

[0040] The adamantyl alkyl silicone oil and anhydride silicone oil were tested using a UV spectrophotometer; Figure 1 It can be seen that the UV spectrum of adamantyl silicone oil has no obvious absorption peak in the 200-400 nm range; the UV spectrum of anhydride silicone oil shows an absorption peak of naphthalene ring at 265 nm and an absorption peak of carbonyl group in anhydride at 233 nm. This is because adamantyl silicone oil reacts with 4-bromo-1,8-naphthalenedicarboxylic anhydride, and the resulting anhydride silicone oil structure contains chromophore naphthalene and anhydride.

[0041] In this scheme, under the action of zinc chloride, the epoxy group in the terminal epoxy silicone oil structure reacts with the hydroxyl group in the 2-adamantane alcohol structure to obtain adamantyl silicone oil. Then, under the action of potassium carbonate, the hydroxyl group in the adamantyl silicone oil structure undergoes a substitution reaction with the active bromine in the 4-bromo-1,8-naphthalenedicarboxylic anhydride structure to obtain anhydride-modified silicone oil. The anhydrides at both ends of this anhydride-modified silicone oil can cure the epoxy adhesive matrix material. It contains a large number of silicon-oxygen bonds, as well as multiple adamantyl groups and naphthyl groups. The three work synergistically to improve the high temperature resistance of epoxy AB adhesive, enabling it to be used stably in high temperature environments without easily becoming sticky and affecting the performance of epoxy AB adhesive.

[0042] Example 1: Preparation of epoxy AB adhesive

[0043] Step 1: Mix 60 parts of bisphenol A type epoxy resin, 1 part of ultraviolet absorber UV-3030, 2 parts of polyethylene oxide, 6 parts of anti-aging graphene oxide and 120 parts of deionized water, and stir thoroughly at a speed of 150 r / min for 1.5 h to obtain epoxy adhesive component A.

[0044] Step 2: Place 20 parts of anhydride silicone oil in 50 parts of deionized water and stir thoroughly at 120 r / min for 2 hours to obtain epoxy resin component B.

[0045] Example 2, Preparation of epoxy AB adhesive

[0046] Step 1: Mix 70 parts of bisphenol A type epoxy resin, 1.5 parts of ultraviolet absorber UV-384, 2.5 parts of dimethyl silicone oil, 7 parts of anti-aging graphene oxide and 135 parts of deionized water, and stir thoroughly at a speed of 155 r / min for 2 hours to obtain epoxy adhesive component A.

[0047] Step 2: Place 25 parts of anhydride silicone oil in 65 parts of deionized water and stir thoroughly at 125 r / min for 2.5 h to obtain epoxy resin component B.

[0048] Example 3, Preparation of epoxy AB adhesive

[0049] Step 1: Mix 80 parts of bisphenol A type epoxy resin, 2 parts of ultraviolet absorber UV-1130, 3 parts of polyoxyethylene, 8 parts of anti-aging graphene oxide and 150 parts of deionized water, and stir thoroughly at a speed of 160 r / min for 2.5 h to obtain epoxy adhesive component A.

[0050] Step 2: Place 30 parts of anhydride silicone oil in 80 parts of deionized water and stir thoroughly at 130 r / min for 3 hours to obtain epoxy resin component B.

[0051] Comparative Example 1: Preparation of Epoxy AB Glue

[0052] Step 1: Mix 70 parts of bisphenol A type epoxy resin, 1.5 parts of ultraviolet absorber UV-384, 2.5 parts of dimethyl silicone oil and 135 parts of deionized water, and stir thoroughly at a speed of 155 r / min for 2 hours to obtain epoxy adhesive component A.

[0053] Step 2: Place 25 parts of anhydride silicone oil in 65 parts of deionized water and stir thoroughly at 125 r / min for 2.5 h to obtain epoxy resin component B.

[0054] Comparative Example 2: Preparation of Epoxy AB Glue

[0055] Step 1: Mix 70 parts of bisphenol A type epoxy resin, 1.5 parts of ultraviolet absorber UV-384, 2.5 parts of dimethyl silicone oil, 7 parts of anti-aging graphene oxide and 135 parts of deionized water, and stir thoroughly at a speed of 155 r / min for 2 hours to obtain epoxy adhesive component A.

[0056] Step 2: Place 25 parts of methylhexahydrophthalic anhydride in 65 parts of deionized water and stir thoroughly at 125 r / min for 2.5 h to obtain epoxy resin component B.

[0057] Comparative Example 3: Preparation of Epoxy AB Glue

[0058] Step 1: Mix 70 parts of bisphenol A type epoxy resin, 1.5 parts of ultraviolet absorber UV-384, 2.5 parts of dimethyl silicone oil, 7 parts of graphene oxide and 135 parts of deionized water, and stir thoroughly at a speed of 155 r / min for 2 hours to obtain epoxy adhesive component A.

[0059] Step 2: Place 25 parts of anhydride silicone oil in 65 parts of deionized water and stir thoroughly at 125 r / min for 2.5 h to obtain epoxy resin component B.

[0060] Performance testing

[0061] ① The epoxy AB adhesives prepared in Examples 1-3 and Comparative Examples 1-3 were mixed with component B and coated onto a steel plate conforming to specifications. After curing at 80°C for 15 minutes, samples were obtained after demolding. The tensile strength of the samples and the samples treated in an aging chamber at 80°C for 72 hours were tested according to standard GB / T1040-2006 to determine the mechanical properties and anti-aging ability of the samples. The specific test results are shown in the table below:

[0062] Tensile strength / MPa Tensile strength after aging / MPa Example 1 42.3 39.2 Example 2 42.9 39.9 Example 3 42.6 39.5 Comparative Example 1 28.8 20.9 Comparative Example 2 39.6 36.2 Comparative Example 3 34.0 27.2

[0063] As shown in the table above, the samples prepared in Examples 1-3 all exhibit excellent mechanical and anti-aging properties. The sample prepared in Comparative Example 1 did not contain anti-aging graphene oxide, resulting in only moderate anti-aging ability. The sample prepared in Comparative Example 2 did not contain anhydride silicone oil and used commercially available epoxy resin curing agent methyl hexahydrophthalic anhydride as the curing agent, resulting in good mechanical properties and anti-aging ability. The sample prepared in Comparative Example 3 directly added graphene oxide without any modification treatment, leading to agglomeration of graphene oxide in the matrix. This resulted in mechanical properties that were inferior to those of the examples. Furthermore, the lack of rhein resulted in poor anti-aging ability.

[0064] ② The epoxy AB adhesives prepared in Examples 1-3 and Comparative Examples 1-3 were mixed with component B and coated onto a steel plate conforming to specifications. After curing at 80°C for 15 minutes, the samples were placed in an oven and treated at 200°C for 24 hours. After cooling to room temperature, the samples were slowly peeled off, and the presence of residual adhesive on the steel plate was observed to determine the high-temperature resistance of the samples. The specific test results are shown in the table below:

[0065] Residual adhesive Example 1 No residue Example 2 No residue Example 3 No residue Comparative Example 1 Slight adhesive residue Comparative Example 2 Heavy residual adhesive Comparative Example 3 Moderate residual adhesive

[0066] As shown in the table above, the samples prepared in Examples 1-3 all have the ability to withstand high temperatures. The sample prepared in Comparative Example 1 has added anhydride silicone oil, and its high temperature resistance is good. The sample prepared in Comparative Example 2 has not added anhydride silicone oil, and its high temperature resistance is poor. Although anhydride silicone oil was added to the sample prepared in Comparative Example 3, the high temperature resistance of the sample is generally poor due to the aggregation of graphene oxide in the matrix.

[0067] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0068] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the scope defined by the inventive concept, they should all fall within the protection scope of the present invention.

Claims

1. A high-temperature resistant epoxy AB adhesive, characterized in that, It includes component A and component B; component A includes the following raw materials in parts by weight: 60-80 parts bisphenol A epoxy resin, 1-2 parts ultraviolet absorber, 2-3 parts defoamer, 6-8 parts anti-aging graphene oxide, and 120-150 parts deionized water; component B includes the following raw materials in parts by weight: 20-30 parts anhydride silicone oil and 50-80 parts deionized water. The preparation method of the anti-aging graphene oxide includes the following steps: (1) Add flake graphite powder to concentrated sulfuric acid, place in an ice bath at 0-4℃, add sodium nitrate and potassium permanganate, stir for 18-24h, add deionized water, cool to room temperature and add hydrogen peroxide solution with a concentration of 1-2mol / L. After the solution changes color, pour out the solution and filter it. Wash with hydrogen chloride solution with a mass fraction of 5-6% and deionized water in turn. Test the supernatant with barium chloride solution with a mass fraction of 2-3mol / L. After no precipitate is produced, dry the product to obtain graphene oxide. (2) Place graphene oxide in N,N-dimethylformamide, disperse it ultrasonically for 15-20 min, add rhein and catalyst, heat to 65-75℃ and react for 6-8 h, filter, wash and vacuum dry to obtain anti-aging graphene oxide; The preparation method of the anhydride-modified silicone oil includes the following steps: S1: Mix toluene with zinc chloride, add terminal epoxy silicone oil and 2-adamantane alcohol, heat to 70-75℃ and react for 5-8 hours, collect the product after vacuum distillation to obtain adamantyl silicone oil; S2: Mix xylene with potassium carbonate, add adamantyl silicone oil and 4-bromo-1,8-naphthalenedicarboxylic anhydride, heat to react, collect the product after vacuum distillation, and obtain anhydride-modified silicone oil.

2. The high-temperature resistant epoxy AB adhesive according to claim 1, characterized in that, The ultraviolet absorber is any one of ultraviolet absorber UV-3030, ultraviolet absorber UV-384, and ultraviolet absorber UV-1130; the defoamer is any one of polyethylene oxide alcohol, dimethyl silicone oil, and polyethylene oxide.

3. The high-temperature resistant epoxy AB adhesive according to claim 1, characterized in that, In step (2), the catalyst is any one of tetrabutylammonium bromide, tetrabutylammonium chloride, and tetrabutylammonium hydroxide.

4. The high-temperature resistant epoxy AB adhesive according to claim 1, characterized in that, In step S1, the viscosity of the terminal epoxy silicone oil is 220-300 cs.

5. The high-temperature resistant epoxy AB adhesive according to claim 1, characterized in that, In step S2, the temperature of the heating reaction is 55-65℃, and the time is 3-5h.

6. A method for preparing a high-temperature resistant epoxy AB adhesive as described in claim 1, characterized in that, Includes the following steps: Step 1: Mix bisphenol A type epoxy resin, ultraviolet absorber, defoamer, anti-aging graphene oxide and deionized water, and stir for 1.5-2.5 hours to obtain epoxy adhesive component A. Step 2: Place the anhydride-modified silicone oil in deionized water and stir for 2-3 hours to obtain epoxy resin component B.

7. The method for preparing a high-temperature resistant epoxy AB adhesive according to claim 6, characterized in that, In step one, the stirring rate is 150-160 r / min.

8. The method for preparing a high-temperature resistant epoxy AB adhesive according to claim 6, characterized in that, In step two, the stirring rate is 120-130 r / min.

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