WO2021227377A1

WO2021227377A1 - Heat resistant adhesive, preparation method therefor, and bonding method for aluminum alloy

Info

Publication number: WO2021227377A1
Application number: PCT/CN2020/123860
Authority: WO
Inventors: 文谟统; 法因莱布·亚历山大; 文琦超; 文勇; 斯塔罗斯坚科·奥莉加; 文杰
Original assignee: 四川川环科技股份有限公司
Priority date: 2020-05-11
Filing date: 2020-10-27
Publication date: 2021-11-18
Also published as: ZA202212341B

Abstract

The present application relates to the field of adhesives, and specifically relates to a heat resistant adhesive, a preparation method therefor, and a bonding method for an aluminum alloy. A new-type heat resistant adhesive is prepared by combining a polysulfone resin with a biphenol compound. The heat resistant adhesive prepared by the preparation method of the present application and the aluminum alloy bonded by the bonding method have a higher bonding strength at room temperature and at 150ºC, and still have a good bonding strength after aging at 150ºC for 200 h. Furthermore, the adhesive obtained by the preparation method has a larger space for modification and adjustment, and can be cooperated with a variety of modifiers to obtain adhesives with different properties, so as to adapt to various application scenarios. In the preparation method for the heat resistant adhesive and the bonding method for an aluminum alloy of the present application, an adhesive and an aluminum alloy bonding material, which have a lower production cost, a simpler process, and a higher bonding strength, can be obtained.

Description

Heat-resistant adhesive, preparation method and bonding method of aluminum alloy

Technical field

This application relates to the field of adhesives, in particular to a method for preparing a heat-resistant adhesive and a method for bonding aluminum alloys.

Background technique

Aluminum alloy is an alloy material obtained by mixing aluminum as the main matrix material and other metal elements. It has the characteristics of light weight and high specific strength. In the case of the same strength, the aluminum alloy material is relatively used. Traditional steel has a smaller mass, which means that aluminum alloy has the characteristics of light weight. Therefore, aluminum alloy materials are widely used in aerospace, high-speed rail, automobiles, ships and other fields; in addition, due to the characteristics of aluminum Compared with other metal materials, aluminum alloy also has the characteristics of corrosion resistance and oxidation resistance. Due to the outstanding properties of aluminum alloys, the amount of aluminum alloys is now increasing, and the application prospects of aluminum alloys are becoming more and more broad.

In the production and application of aluminum alloy parts, we often combine the aluminum alloy parts with other components to play an integral role. Generally, the existing technology generally uses welding, brazing or adhesive connection to complete the aluminum alloy. The connection between parts or aluminum alloy parts and other components. Among them, there are various types of aluminum alloy adhesives, and various adhesives can be flexibly selected according to the different materials to be bonded. That is to say, aluminum alloy adhesives can be applied to various bonding objects of aluminum alloy, so it has a wide range of practicability; It is important that most adhesives need to be heated and cured after bonding. However, compared to welding or brazing, the temperature conditions required for curing of the adhesive are much milder, because the high temperature will affect the aluminum alloy The structure and performance are adversely affected. Therefore, the choice of aluminum alloy adhesive for bonding and connection has a lower impact on the aluminum alloy material, and an aluminum alloy member with higher strength and rigidity can be obtained.

Summary of the invention

The present invention provides the technical content of the first aspect, and specifically relates to a method for preparing a heat-resistant adhesive, including the following steps:

1) According to parts by mass, add 12-18 parts of the first reactant to 82-88 parts of the second reactant, stir and mix uniformly at 150-170°C, until the first reactant is completely dissolved in the second reaction To obtain the first mixture;

2) Cool the first mixture to 110～130°C;

3) Add the catalyst dropwise to the first mixture, and stir at 130-150°C for 5-10 min to obtain the adhesive, wherein the mass ratio of the catalyst to the first mixture is (0.30-0.38): 20;

The first reactant is one or more of polysulfone resin, polyphenylsulfone resin or polyethersulfone resin, the second reactant includes a bisphenol compound, and the bisphenol compound is bisphenol A or One or more of bisphenol E;

The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 70-90°C, stirring for 5-10 min until the cobalt acetylacetonate is completely dissolved; wherein the nonylphenol and cobalt acetylacetonate The mass ratio is 4: (0.32～0.36).

Optionally, the preparation method includes the following steps:

1) In terms of parts by mass, add 15 parts of the first reactant to 85 parts of the second reactant, stir and mix uniformly at 160°C, until the first reactant is completely dissolved in the first reactant to obtain the first mixture ；

2) Cool the first mixture to 120°C;

3) Add the catalyst dropwise to the first mixture, and stir at 140°C for 5-10 minutes to obtain the adhesive, wherein the mass ratio of the catalyst to the first mixture is 0.34:20;

The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 80°C, stirring for 5-10 minutes until cobalt acetylacetonate is completely dissolved; wherein the mass ratio of nonylphenol to cobalt acetylacetonate It is 4: 0.34.

Optionally, the second reactant includes a bisphenol compound and an epoxy resin, the bisphenol compound is one or more of bisphenol A or bisphenol E, and the epoxy resin is E-51, E -44, one or more of E-42, the epoxy resin does not exceed 20% of the total mass of the second reactant.

Optionally, a thixotropic agent is added to the reaction system of the first reactant and the second reactant, the thixotropic agent is fumed silica, and the amount of the thixotropic agent is the first reactant and the second reactant. 1% to 2% of the total weight of the reactants.

Optionally, an antioxidant is added to the reaction system of the first reactant and the second reactant, and the amount of the antioxidant is 0.5% to 1% of the total weight of the first reactant and the second reactant The antioxidant is one or more of antioxidant 1010 and antioxidant 264.;

Optionally, a coupling agent is added to the reaction system of the first reactant and the second reactant, the coupling agent is a silane coupling agent, and the amount of the coupling agent is the first reactant and the second reactant. 1% to 3% of the total weight of the reactants.

Optionally, after step 3) is completed, a vacuum device is used to vacuum the adhesive until no more bubbles are released in the adhesive.

This application also provides the technical content of the second aspect, which relates to the heat-resistant adhesive prepared by any of the foregoing methods.

This application also provides the technical content of the third aspect, and specifically relates to a bonding method of aluminum alloy, using the aforementioned heat-resistant adhesive, and the bonding method includes the following steps:

1) Use acetone or high-concentration alcohol to derust the surface of aluminum alloy;

2) Use a grinder or sandpaper to polish the bonding area of the aluminum alloy sheet. When using sandpaper, first use low-mesh sandpaper for rough grinding, and then use high-mesh sandpaper for fine grinding step by step until there is no visual friction;

3) The aluminum alloy is immersed in a pickling solution for pickling for 10-15 minutes, and the temperature of the pickling solution is 60-65°C;

4) Wash the pickled aluminum alloy with pure water at 65～70℃ for 15～25min. After washing, use hot air to dry the aluminum alloy;

5) Use a vacuum device to vacuum the adhesive until the adhesive no longer releases bubbles;

6) Apply the adhesive evenly to the surface of the aluminum alloy; then paste the aluminum alloy together and press it tightly;

7) The pasted aluminum alloy is cured at a temperature of 180°C for 7-10 hours, and then heated to 250°C for 1 to 2 hours.

Optionally, in step 3), the preparation method of the pickling solution is: use deionized water to dissolve ferric sulfate, and then slowly add sulfuric acid solution, where each 1L of deionized water corresponds to 300g ferric sulfate and 400ml sulfuric acid solution; The concentration of the sulfuric acid solution is 1.84 g/cm ³ .

Optionally, the adhesive formulation includes epoxy resin. In step 7), the pasted aluminum alloy is cured at a temperature of 180°C for 8-10 hours, and then heated to 250°C for 1.5-2 hours.

Optionally, after step 5) is completed, the aluminum alloy is pre-heated before step 6), so that the temperature of the aluminum alloy is heated to 80-120°C.

This application prepares a new type of heat-resistant adhesive through the combination of polysulfone resin and bisphenol compound. Aluminum alloy has high bonding strength at room temperature and 150°C, and still has good bonding strength after aging at 150°C*200h; and the preparation method obtains a large room for modification and adjustment of the adhesive, which can be used in many combinations. A variety of modifiers to obtain adhesives with different properties to adapt to a variety of application scenarios. The heat-resistant adhesive and aluminum alloy bonding method described in the present application can obtain adhesives and aluminum alloy bonding materials with lower production costs, simpler processes, and higher bonding strength.

Detailed ways

The solution will be described below in conjunction with specific implementations.

This application provides a heat-resistant adhesive, a preparation method thereof, and an adhesive prepared by the method. Specifically, the preparation method of the heat-resistant adhesive includes the following steps:

1) According to parts by mass, add 12-18 parts of the first reactant to 82-88 parts of the second reactant, stir and mix uniformly at 150-170°C, until the first reactant is completely dissolved in the second reaction A first mixture is obtained from the product, and the first reactant is one or more of polysulfone resin (PSU), polyphenylsulfone resin (PPSU), or polyethersulfone resin (PESU). It should be noted that, In this application, the polysulfone resin refers to bisphenol A polysulfone; the second reactant includes a bisphenol compound, and the bisphenol compound is specifically one or more of bisphenol A or bisphenol E ; At 150 ~ 170 ℃, the first reactant can slowly dissolve in the second reactant, this step takes a long time, in the case of using a magnetic stirrer to stir, the required time is about 3.5 ~ 4.5h Between, as a preference, in order to accelerate the dissolution speed, the rotation speed of the magnetic stirrer should not be lower than 1200 rpm;

2) Cool the first mixture to 110-130°C. The cooling method can be natural cooling or room temperature water bath cooling. In order to prevent the precipitation of the first reactant, the cooling rate should not be too fast;

3) Add the catalyst dropwise to the first mixture, and stir at 130-150° C. for 5-10 minutes to obtain the adhesive, wherein the mass ratio of the catalyst to the first mixture is (0.30-0.38):20.

After step 3) is completed, a vacuum device can be used to vacuum the adhesive until it no longer releases bubbles, or this step can also be performed before the adhesive is used.

The preparation method of the catalyst described in this application is: adding cobalt acetylacetonate to nonylphenol at 70-90°C, stirring for 5-10 minutes until the cobalt acetylacetonate is completely dissolved; among them, nonylphenol and acetylacetone The mass ratio of cobalt is 4: (0.32 ~ 0.36).

In the first reactant described in this application, the ratio between the polysulfone resin, polyphenylsulfone resin or polyethersulfone is any ratio; in the second reactant, the ratio of bisphenol A and bisphenol E The ratio is an arbitrary ratio.

Through the above steps, we can obtain a heat-resistant adhesive with a certain bonding strength, which is particularly suitable for use as an adhesive between aluminum alloy materials. In order to further improve the performance of the adhesive, on the basis of the above, we can also make some improvements. Specifically, the second reactant can be added with a certain amount of epoxy in addition to bisphenol A, bisphenol E or a mixture thereof. The epoxy resin is one or more of E-51, E-44, E-42, and the epoxy resin does not exceed 20% of the total mass of the second reactant. The epoxy resin described in this application It is a bisphenol A type epoxy resin, which has very excellent adhesive properties, and it has good compatibility with bisphenol compounds, which can significantly enhance the bonding strength.

In addition, as an option, the heat-resistant adhesive described in this application can also be added with other modifiers according to actual needs; considering that the effective action time of the adhesive after use is extended or it may be applied to scenes that are prone to oxidation such as exposure, high temperature, etc. In the preparation process of the heat-resistant adhesive described in this application, an antioxidant may be added. The antioxidant may be a common antioxidant on the market or a combination thereof. The amount of the antioxidant should be controlled in the first reaction. 0.5% to 1% of the total weight of the second reactant; In order to further enhance the bonding effect of the adhesive to metal, making it more suitable for bonding between metals, an appropriate amount can also be added to the reaction system described in this application. Coupling agent, the amount of the coupling agent should be controlled within 1% to 3% of the total weight of the first reactant and the second reactant. As a preference, a silane coupling agent can be used; In the case of the adhesive, in order to improve its construction performance and prevent the adhesive from sagging, an appropriate amount of thixotropic agent can be added to the reaction system, and the amount of the thixotropic agent should be controlled within the total amount of the first reactant and the second reactant. 1% to 2% by weight, fumed silica is used as the thixotropic agent; similarly, in this reaction system, an appropriate amount of other modifiers can also be added to make it have different properties for various applications Scenes.

The heat-resistant adhesive described in the present application is mainly used for bonding between aluminum alloy plates. Of course, it is also suitable for bonding other substances, which will not be repeated here. For the bonding of aluminum alloy, this application also provides a bonding method of the heat-resistant adhesive to aluminum alloy plates, which mainly includes the following steps:

1) Derusting on the surface of aluminum alloy sheet can be wiped with acetone or high-concentration alcohol;

2) The surface of the aluminum alloy plate is polished to make the surface relatively flat, which can produce a better bonding effect. Here you can use a special grinder or sandpaper for polishing. When using sandpaper, you should first use a lower mesh sandpaper Carry out rough grinding, and then use high-mesh sandpaper for fine grinding step by step, so that no friction marks can be seen in the end.

3) The aluminum alloy plate is immersed in a pickling solution for 10-15 minutes for pickling, and the temperature of the pickling solution is 60-65°C; as an option, this application provides a method for preparing the pickling solution, Specifically, ferric sulfate is dissolved in deionized water. Each 1L of deionized water dissolves corresponding to 300g of ferric sulfate, and then adds 400ml of sulfuric acid solution. It should be noted that since sulfuric acid will emit a lot of heat when adding sulfuric acid, it must be added slowly Sulfuric acid solution to avoid sulfuric acid splashing and hurting people. The mass concentration of the sulfuric acid solution is 1.84g/cm ³ ; it should be noted that the pickling solution is easy to deteriorate, and it is preferably prepared within one week before pickling the aluminum alloy sheet , Of course, other pickling solutions that also have pickling effect can also be used;

4) Rinse and dry the aluminum alloy. Use 65-70℃ pure water to rinse for 15-25 minutes. Finally, take out the aluminum alloy and dry it with hot air; after drying, place the aluminum alloy in a clean container, and place it in a clean container within 12 hours. Carry out bonding operations in-house;

5) Before pasting the aluminum alloy sheet, use a vacuum device to vacuum the adhesive to remove bubbles in the adhesive, subject to the adhesive no longer releasing bubbles;

6) Apply the adhesive evenly to the side of the two aluminum alloy plates that need to be bonded. As a preference, heat the aluminum alloy before applying the adhesive to the surface of the aluminum alloy plate, specifically heating the aluminum alloy to 80-120 ℃, then apply adhesive to it;

7) Paste the two aluminum alloy plates together and press tightly;

8) Curing at 180°C for 7-10 hours, and then heating to 250°C for curing for 1 to 2 hours. After the curing is completed, the bonded aluminum alloy sheet will be obtained.

In addition, the adhesive layer of aluminum alloy adhesive bonded by the above method can be removed by 99% n-butylamine solution and 99% methyl pyrrolidone solution. The specific operation method is: at room temperature, the adhesive layer will be attached The aluminum alloy sheet is soaked in a 99% concentration n-butylamine solution for 3-8 hours; then it is soaked in a 99% concentration A-grade pyrrolidone solution for 2 to 3 minutes; finally, the adhesive layer can be removed by rinsing it under clean water.

The following specific examples illustrate several specific implementations of the adhesive described in this application and the preparation method thereof, and the properties of the prepared adhesive.

Example 1

The preparation steps of the adhesive described in this embodiment are as follows:

1) Add 17g of the second reactant into a clean flask, the flask is set on a constant-temperature magnetic stirrer, the temperature of the constant-temperature magnetic stirrer is set to 160°C, and then 3g of the first reactant is slowly added to the second reactant, Keep stirring during this process, set its speed to 1300 rpm, and stir for about 4 hours until the first reactant is completely dissolved in the second reactant to obtain the first mixture;

2) Wait for the first mixture to cool to 120°C;

3) Add the catalyst dropwise to the first mixture, and then stir at 140°C for 5-10 minutes to obtain the adhesive, wherein the amount of the catalyst is 0.34g,

In this embodiment, the first reactant is a polysulfone resin, the second reactant is a bisphenol compound, and the bisphenol compound is bisphenol A. The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 80°C, stirring for 5-10 minutes until cobalt acetylacetonate is completely dissolved; wherein the mass ratio of nonylphenol to cobalt acetylacetonate It is 4: 0.34.

Example 2

On the basis of Example 1, the first reactant described in this application is bisphenol E, and the second reactant is a mixture of polyphenylsulfone resin and polyethersulfone resin in a mass ratio of 1:1. The rest are the same as in Example 1.

Example 3

1) In a clean flask, add 17g of the second reactant and 0.03g of coupling agent, the coupling agent is a silane coupling agent, the brand is KH550; the flask is set on a constant temperature magnetic stirrer, the constant temperature magnetic stirrer Set the temperature to 160°C, then slowly add 3g of the first reactant to the second reactant, keep stirring during this process, set the rotation speed to 1300 rpm, and stir for about 4 hours until the first reactant is completely dissolved in the second reactant Get the first mixture;

2) Wait for the first mixture to cool to 120°C;

3) Add the catalyst dropwise to the first mixture, and then stir at 140°C for 5-10 minutes to obtain the adhesive, wherein the amount of the catalyst is 0.38g,

In this embodiment, the first reactant is a mixture of polysulfone resin, polyphenylsulfone resin, and polyethersulfone resin in a mass ratio of 1:1:1, and the second reactant is a bisphenol compound The bisphenol compound is a mixture of bisphenol A and bisphenol E in a mass ratio of 1:1. The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 80°C, stirring for 5-10 minutes until cobalt acetylacetonate is completely dissolved; wherein the mass ratio of nonylphenol to cobalt acetylacetonate It is 4: 0.36.

Example 4

1) Add 16.4g of the second reactant in a clean flask, the flask is set on a constant-temperature magnetic stirrer, the temperature of the constant-temperature magnetic stirrer is set to 160°C, and then 3.6g of the first reactant is slowly added to the second reactant In this process, keep stirring during this process, set the rotation speed to 1300 rpm, and stir for about 4 hours until the first reactant is completely dissolved in the second reactant to obtain the first mixture;

2) Add 0.1～0.2g of antioxidant to the first mixture. The antioxidant is a combination of antioxidant 1010 and antioxidant 264, and the mass ratio of antioxidant 1010 to antioxidant 264 is Any ratio, after adding the antioxidant, continue to stir for 10-15 minutes to obtain the second mixture;

3) Wait for the second mixture to cool to 120°C;

4) Add the catalyst dropwise to the second mixture, and then stir at 140°C for 5-10 minutes to obtain the adhesive, wherein the amount of the catalyst is 0.38g,

Example 5

1) Add 17.6g of the second reactant into a clean flask, the flask is set on a constant-temperature magnetic stirrer, the temperature of the constant-temperature magnetic stirrer is set to 160°C, and then 2.4g of the first reactant is slowly added to the second reactant In this process, keep stirring during this process, set the rotation speed to 1300 rpm, and stir for about 4 hours until the first reactant is completely dissolved in the second reactant to obtain the first mixture;

2) Wait for the first mixture to cool to 120°C;

3) Add the catalyst dropwise to the first mixture, and then stir at 140°C for 5-10 minutes to obtain the adhesive, wherein the amount of the catalyst is 0.3g,

In this embodiment, the first reactant is a polysulfone resin, the second reactant includes a bisphenol compound and an epoxy resin, the bisphenol compound is bisphenol A, and the epoxy resin grade is E- 51. The mass of the epoxy resin is 3.2 g. The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 80°C, stirring for 5-10 minutes until cobalt acetylacetonate is completely dissolved; wherein the mass ratio of nonylphenol to cobalt acetylacetonate It is 4: 0.32.

Example 6

On the basis of Example 5, in this example, 0.1-0.2 g of a thixotropic agent is added during the process of adding the first reactant to the second reactant, and the thixotropic agent is fumed silica.

According to the GBT 7124 standard, the tensile shear strength of the adhesives prepared in Examples 1 to 6 was measured. The specific method is:

The model of the aluminum alloy plate used for the test in this application is 2024T3 aviation aluminum alloy. The aluminum alloy plate is cut into standard sizes for use, and the test sample is prepared according to the following steps:

1) According to the standard, paste the aluminum alloy sheet with a marking on one side, and divide the sheet into two areas of 12.5*25*1.6mm and 87.5*25*1.6mm, of which the area of 12.5*25*1.6mm is the part where the adhesive is applied. That is to say, the bonding area of the two aluminum alloy plates is 12.5mm*25mm, and this area is the bonding area of the aluminum alloy plates;

2) Pre-treat the aluminum alloy sheet and the adhesive according to steps 1) to 5) of the aforementioned aluminum alloy sheet bonding method. After the aluminum alloy is polished, the thickness of the aluminum alloy to be bonded is measured before pickling. When measuring thickness, at least four different positions should be selected to test the thickness separately, and the thickness of each position shall not deviate by 1.6mm by more than 0.1mm;

3) Heat the aluminum alloy to 100°C, and then use a glass rod to drop the vacuum-treated adhesive onto the bonding area of the aluminum alloy plate and apply it evenly. The amount of adhesive is controlled to one or two drops to cover evenly and completely. The bonding area shall prevail;

4) Use fixtures to assist in bonding two aluminum alloy plates, and use Teflon gaskets and aluminum alloy precipitation to protect the surface of the aluminum alloy plates and ensure that the bonding surfaces of each group of samples are parallel to each other;

5) Put the bonded aluminum alloy plate in a constant temperature oven, bake at 180°C for 8 hours, and heat up to 250°C and bake for 1 hour;

6) After baking, measure the total thickness of the bonding area of the two alloy plates, and calculate the glue layer thickness based on the previously measured plate thickness;

7) Repeat the above steps to prepare ten sets of test samples for the adhesive prepared in each embodiment;

According to the above-mentioned sample preparation method, the thickness of the plate and the thickness of the glue layer in each embodiment are measured, and the results are as follows:

In this application, an Instron tensile machine is used to measure the sample, where the set parameters are: the tensile speed is 1mm/min, and the length of the sample clamped by the gripper of the tensile machine is 37.5±0.2mm. The final measured results are as follows:

According to the GJB446 standard and the above method, ten sets of test samples for testing the 90° peel strength are prepared. In this application, the Instron tensile machine is used to measure the samples. The set parameter is: the tensile speed is 100mm/min, and the final measurement is The results are as follows:

In addition, for the test samples of Examples 1 to 6 prepared by the above method, they were subjected to 150℃*200h aging treatment, and then tested their normal temperature/high temperature tensile shear strength and normal temperature/high temperature 90° peel strength according to the above method , The measured results are shown in the following table:

From the above data, it can be seen that the adhesive prepared by the preparation method described in this application has a certain bonding strength when bonding aluminum alloy plates, and can be applied to the bonding of aluminum alloy plates, and the bonding strength is at a high temperature of 150°C. There is only an insignificant decrease. In the above examples, the bonding strength of Example 5 and Example 6 is relatively strong, and it can be concluded from the strength test after aging that when the second reactant includes epoxy resin, the above The adhesive prepared by the preparation method is not completely cured when cured at high temperature. Therefore, for the embodiment with epoxy resin, the curing time can be appropriately extended to obtain a better bonding effect. Specifically, it is cured at 180°C. ～10h, then heat to 250℃ and cure for 1.5～2h.

The same or similar parts in the various embodiments in the specification of this application can be referred to each other. In particular, for the system and terminal embodiments, since the methods therein are basically similar to the method embodiments, the description is relatively simple, and the relevant details can be referred to the descriptions in the method embodiments.

It should be noted that in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these There is any such actual relationship or sequence between entities or operations. Moreover, the terms "include", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes those that are not explicitly listed Other elements of, or also include elements inherent to this process, method, article or equipment. If there are no more restrictions, the element defined by the sentence "including a..." does not exclude the existence of other identical elements in the process, method, article, or equipment that includes the element.

Of course, the above description is not limited to the above examples. The technical features not described in this application can be realized by or using existing technology, and will not be repeated here; As an alternative, this application is only described in detail with reference to the preferred embodiments. A person of ordinary skill in the art should understand that changes and changes made by persons of ordinary skill in the art within the essential scope of the application Modifications, additions or replacements do not depart from the purpose of this application, and should also fall within the scope of protection of the claims of this application.

Claims

A method for preparing a heat-resistant adhesive, which is characterized in that it comprises the following steps:

1) According to parts by mass, add 12-18 parts of the first reactant to 82-88 parts of the second reactant, stir and mix uniformly at 150-170°C, until the first reactant is completely dissolved in the second reaction To obtain the first mixture;

2) Cool the first mixture to 110～130°C;

3) Add the catalyst dropwise to the first mixture, and stir at 130-150°C for 5-10 min to obtain the adhesive, wherein the mass ratio of the catalyst to the first mixture is (0.30-0.38): 20;

The first reactant is one or more of polysulfone resin, polyphenylsulfone resin or polyethersulfone resin, the second reactant includes a bisphenol compound, and the bisphenol compound is bisphenol A or One or more of bisphenol E;

The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 70-90°C, stirring for 5-10 min until the cobalt acetylacetonate is completely dissolved; wherein the nonylphenol and cobalt acetylacetonate The mass ratio is 4: (0.32～0.36).
The preparation method according to claim 1, characterized in that it comprises the following steps:

1) In terms of parts by mass, add 15 parts of the first reactant to 85 parts of the second reactant, stir and mix uniformly at 160°C, until the first reactant is completely dissolved in the first reactant to obtain the first mixture ；

2) Cool the first mixture to 120°C;

3) Add the catalyst dropwise to the first mixture, and stir at 140°C for 5-10 minutes to obtain the adhesive, wherein the mass ratio of the catalyst to the first mixture is 0.34:20;

The preparation method of the catalyst is: adding cobalt acetylacetonate to nonylphenol at 80°C, stirring for 5-10 minutes until cobalt acetylacetonate is completely dissolved; wherein the mass ratio of nonylphenol to cobalt acetylacetonate It is 4: 0.34.
The preparation method according to claim 1, wherein the second reactant comprises a bisphenol compound and an epoxy resin, and the bisphenol compound is one or more of bisphenol A or bisphenol E, and The epoxy resin is one or more of E-51, E-44, and E-42, and the epoxy resin does not exceed 20% of the total mass of the second reactant.
The preparation method according to claim 3, wherein a thixotropic agent is added to the reaction system of the first reactant and the second reactant, the thixotropic agent is fumed silica, and the thixotropic agent is The amount used is 1%-2% of the total weight of the first reactant and the second reactant.
The preparation method according to claim 1, wherein an antioxidant is added to the reaction system of the first reactant and the second reactant, and the amount of the antioxidant is the first reactant and the second reactant. 0.5% to 1% of the total weight of the substance; the antioxidant is one or more of antioxidant 1010 and antioxidant 264.
The preparation method according to claim 1, wherein a coupling agent is added to the reaction system of the first reactant and the second reactant, and the coupling agent is a silane coupling agent. The amount used is 1% to 3% of the total weight of the first reactant and the second reactant.
The preparation method according to claim 1, wherein after step 3) is completed, a vacuum device is used to vacuum the adhesive until no more bubbles are released in the adhesive.
The heat-resistant adhesive prepared by any one of the preparation methods of claims 1-7.
The bonding method of aluminum alloy is characterized in that the heat-resistant adhesive of claim 8 is used, and the bonding method includes the following steps:

1) Use acetone or high-concentration alcohol to derust the surface of aluminum alloy;

2) Use a grinder or sandpaper to polish the bonding area of the aluminum alloy sheet. When using sandpaper, first use low-mesh sandpaper for rough grinding, and then use high-mesh sandpaper for fine grinding step by step until there is no visual friction;

3) The aluminum alloy is immersed in a pickling solution for pickling for 10-15 minutes, and the temperature of the pickling solution is 60-65°C;

4) Wash the pickled aluminum alloy with pure water at 65～70℃ for 15～25min. After washing, use hot air to dry the aluminum alloy;

5) Use a vacuum device to vacuum the adhesive until the adhesive no longer releases bubbles;

6) Apply the adhesive evenly to the surface of the aluminum alloy; then paste the aluminum alloy together and press it tightly;

7) The pasted aluminum alloy is cured at a temperature of 180°C for 7-10 hours, and then heated to 250°C for 1 to 2 hours.
The bonding method according to claim 9, wherein in step 3), the preparation method of the pickling solution is: use deionized water to dissolve iron sulfate, and then slowly add the sulfuric acid solution, wherein every 1L of deionized Water corresponds to 300 g of iron sulfate and 400 ml of sulfuric acid solution; the concentration of the sulfuric acid solution is 1.84 g/cm 3 .
The bonding method according to claim 9, wherein the adhesive formula includes epoxy resin, and in step 7), the pasted aluminum alloy is cured at a temperature of 180° C. for 8-10 hours, and then the temperature is raised. Cure at 250℃ for 1.5～2h.
The bonding method according to claim 9, wherein after step 5) is completed, the aluminum alloy is pre-heated before step 6) to heat the aluminum alloy to a temperature of 80-120°C.