High-temperature reaction type adhesive film as well as preparation and use methods thereof

Abstract

The invention relates to the technical field of adhesives, in particular to a high-temperature reaction type adhesive film as well as a preparation method and a use method thereof. The adhesive comprises 40-60 parts of phenolic resin, 40-60 parts of nitrile rubber, 10-20 parts of tackifying resin, 10-20 parts of reactive resin, 3-9 parts of a curing agent, 0.5-2 parts of a vulcanizing agent, 0.5-2 parts of an accelerant, 5-15 parts of filler, 0.5-1 part of an antioxidant and 1-3 parts of carbon black. According to the invention, the reaction type resin is used, so that the reaction can be rapidly carried out at a certain temperature, the reaction activity of an adhesive system is improved, the adhesion to a bonding substrate is increased, the curing time and the curing pressure can be effectively reduced, and good bonding strength can be achieved under the conditions that the curing time is 2-3 minutes and the minimum curing pressure is 0.4 MPa. And the tackifying resin can provide a small amount of initial viscosity for the adhesive film, and is beneficial to bonding and positioning of the adhesive film. The problems of low curing speed and poor bonding positioning of the phenolic aldehyde-butyronitrile adhesive film are solved, and the industrial application of the adhesive film is favorably expanded. The adhesive film is simple and convenient to operate, quick, efficient, green, environment-friendly, good in comprehensive performance and suitable for the requirements of industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of adhesives, in particular to a high-temperature reactive adhesive film and a preparation and use method thereof. Background Art

[0002] Adhesives, also known as adhesives, adhesives, or simply glue, are a type of natural or synthetic substance that connects two or more identical or different parts (or materials) together strongly and permanently through the effects of interface adhesion and material cohesion. Adhesives can bond the same or different materials such as metal, glass, rubber, and plastic into one, giving objects their respective application functions.

[0003] Phenolic resin is resistant to weak acids and weak bases, decomposes in strong acids, and corrodes in strong bases; it is insoluble in water, but soluble in organic solvents such as acetone and alcohol. Phenolic resin is mainly obtained by polycondensation of phenol and formaldehyde or their derivatives, and is one of the earliest synthetic resins used in the adhesive industry. Phenolic resin has excellent bonding properties, high temperature resistance, water resistance, oil resistance, low price, easy production, and easy modification, and its application is becoming more and more extensive.

[0004] However, existing phenolic resin adhesives still have disadvantages such as high brittleness, low peelability, easy cracking, poor toughness, and slow curing speed.

[0005] Phenolic resin-nitrile rubber adhesive prepared by adding vulcanizing agent and reinforcing agent to nitrile rubber and dissolving and homogenizing with phenolic resin can effectively improve the strength and toughness of the adhesive. In this reaction system, in addition to the curing agent, it is sometimes necessary to add rubber vulcanizing agent and vulcanization accelerator, such as sulfur, zinc oxide, peroxide, organic accelerator, etc. At the same time, filler is added to adjust the thermal expansion coefficient, improve elastic modulus, bonding strength and impact resistance, heat resistance, etc., and can also adjust the viscosity of the adhesive.

[0006] When choosing solvents for phenolic-nitrile adhesives, storage stability, toxicity, flammability, volatility and cost must be considered, such as ethyl acetate, butyl acetate, methyl ethyl ketone, etc. Phenolic-nitrile adhesives have high bonding strength, good flexibility, and good anti-peeling properties; they have a wide operating temperature range and can be used for a long time at 60-150°C; they have excellent aging resistance; they have a wide range of uses and can be used to bond rubber, metal, plastic and other materials. Based on the above advantages, high-temperature reactive phenolic-nitrile adhesive films have broad application prospects in aerospace, automotive, electronics and other fields.

[0007] Compared to liquid adhesives that require mixing, curing, and clamping, phenolic-nitrile films are easy to handle, can adapt to harsh environmental conditions, and are cleaner during use, avoiding dripping or spilling. In addition, the advantages of phenolic-nitrile films include the ability to provide consistent thickness at the joints. In addition, phenolic-nitrile films can form bonds that withstand loads and stresses, and can create strong and reliable bonds between different material substrates. Therefore, in the engineering field, they are widely used to connect different materials such as metals, composites, and plastics to maintain mechanical properties and chemical stability and extend service life.

[0008] However, the current phenolic-nitrile film still has the disadvantage of slow curing speed. Under the curing temperature condition of 160°C, most of the curing time and curing pressure are relatively large, the curing time is at least 10 minutes, and the curing pressure is at least 1-5MPa. This limits the application of phenolic-nitrile film to a certain extent and is not conducive to efficient industrial production.

[0009] In order to solve the above problems, the present invention provides a high temperature reactive adhesive film and a preparation and use method thereof. Summary of the invention

[0010] The object of the present invention is to provide a high temperature reactive adhesive film and a preparation and use method thereof, so as to solve the problems raised in the above background technology.

[0011] In order to solve the above technical problems, the present invention provides the following technical solutions: a high temperature reactive adhesive film, comprising the following components by weight: 40-60 parts of phenolic resin, 40-60 parts of nitrile rubber, 10-20 parts of tackifying resin, 10-20 parts of reactive resin, 3-9 parts of curing agent, 0.5-2 parts of vulcanizing agent, 0.5-2 parts of accelerator, 5-15 parts of filler, 0.5-1 parts of antioxidant, and 1-3 parts of carbon black.

[0012] More optimally, the phenolic resin is at least one of linear phenolic resin, methyl-modified phenolic resin, tert-butyl-modified phenolic resin, and cardanol-modified phenolic resin.

[0013] More optimally, the nitrile content of the nitrile rubber is 30%-45%, and the Mooney viscosity is 60-80.

[0014] More optimally, the tackifying resin is at least one of petroleum resin, rosin resin, and terpene resin.

[0015] More optimally, the reactive resin is at least one of thermosetting phenolic resin, epoxy-modified phenolic resin, epoxy resin, KH550, and KH560.

[0016] More optimally, the curing agent is any one of hexamethylenetetramine, paraformaldehyde, and dicumyl peroxide.

[0017] More optimally, the vulcanizing agent is at least one of sulfur, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, and tetrabenzylthiuram disulfide.

[0018] More optimally, the accelerator is at least one of 2-mercaptobenzothiazole, dibenzothiazole disulfide, N-cyclohexyl-2-benzothiazole sulfenamide, N,N-dicyclohexyl-2-benzothiazole sulfenamide, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, and tetrabenzylthiuram disulfide.

[0019] More optimally, the filler is at least one of zinc oxide, magnesium oxide, barium sulfate, talc, and silicon dioxide.

[0020] A method for preparing a high temperature reactive adhesive film, used for preparing any of the above-mentioned high temperature reactive adhesive films, comprises the following steps:

[0021] S1, cutting the phenolic resin and the nitrile rubber into suitable sizes, adding them into ethyl acetate, stirring and dissolving them to obtain an ethyl acetate solution A of the phenolic resin and an ethyl acetate solution B of the nitrile rubber;

[0022] S2, adding solution B and the tackifying resin of claim 1, reactive resin, curing agent, vulcanizing agent, filler, antioxidant, carbon black to solution A in a certain proportion, adding an appropriate amount of ethyl acetate, adjusting the solid content of the solution to 25-45%, stirring until the mixture is uniform, and obtaining an ethyl acetate glue solution C of phenolic resin and nitrile rubber;

[0023] S3, coating the adhesive liquid C on the release paper into a thin film by a coating machine;

[0024] S4, putting the film into an oven, heating it, drying it and cutting it to obtain a film.

[0025] More optimally, in step S4, the temperature during heating is 50-90°C.

[0026] More optimally, in step S4, the drying time is 0.5-3h.

[0027] More optimally, in step S4, the thickness of the adhesive film after cutting is 25-100 μm.

[0028] A method for using a high temperature reactive adhesive film, which is used for using any of the above high temperature reactive adhesive films, comprises the following steps: pre-pasting the adhesive film at a desired bonding position of a substrate under room temperature, at which time the adhesive film has initial adhesiveness and is used for pre-pasting positioning; then hot pressing is performed under certain temperature and pressure conditions to produce a chemical cross-linking reaction, and then cooled to room temperature to maintain high adhesiveness

[0029] More optimally, the substrate is at least one of stainless steel 304, stainless steel 316, anodized aluminum, and nickel-plated aluminum.

[0030] More optimally, the hot pressing temperature is 160°C, the hot pressing pressure is 0.4-3MPa, and the pre-lamination time is 120-180s.

[0031] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0032] (1) In the present invention, the added nitrile rubber has the advantages of good oil resistance, high wear resistance, good heat resistance and strong adhesion, and has good compatibility with phenolic resin. The adhesive cross-linking and curing reaction of nitrile rubber and phenolic resin is utilized to make the adhesive film have good toughness, high strength and high temperature resistance.

[0033] (2) The current phenolic-nitrile adhesive film still has the disadvantage of slow curing speed. Under the curing temperature condition of 160°C, most of the curing time and curing pressure are relatively large. The curing time is at least 10 minutes, and the curing pressure must be at least 1-5MPa, and the bonding strength can reach 15-20MPa. In the present invention, the reactive resin can react quickly at a certain temperature, improve the reactivity of the adhesive system, increase the adhesion to the bonding substrate, and effectively reduce the curing time and curing temperature. Under the conditions of curing time of 2-3 minutes and curing pressure of at least 0.4MPa, the bonding strength can reach 15-20MPa.

[0034] (3) The preparation and use methods of the present invention can obtain a high-temperature reactive phenolic-nitrile adhesive film with a smooth surface, simple operation, rapidity, high efficiency and good comprehensive performance. DETAILED DESCRIPTION

[0035] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0036] Example 1

[0037] A high-temperature reactive phenolic-nitrile adhesive film comprises the following raw materials by weight: 60 parts of thermoplastic phenolic resin (methyl modified phenolic resin), 40 parts of nitrile rubber (Mooney viscosity is 70), 10 parts of petroleum resin, 10 parts of thermosetting phenolic resin, 6 parts of hexamethylenetetramine, 1 part of sulfur, 2 parts of tetrabenzylthiuram disulfide, 2 parts of zinc oxide, 10 parts of magnesium oxide, 10760.5 parts of antioxidant, and 2 parts of carbon black N550.

[0038] Prepare the high temperature reactive phenolic-nitrile film as follows:

[0039] (1) firstly cutting the phenolic resin and the nitrile rubber into suitable sizes, adding them into ethyl acetate, stirring and dissolving them, to obtain an ethyl acetate solution A of the phenolic resin and an ethyl acetate solution B of the nitrile rubber;

[0040] (2) Then, solution B and the tackifying resin, reactive resin, curing agent, vulcanizing agent, filler, antioxidant and carbon black according to claim 1 are added to solution A in a certain proportion, and an appropriate amount of ethyl acetate is added to adjust the solid content of the solution to 25-45%, and the mixture is stirred until the mixture is uniformly mixed to obtain an ethyl acetate glue solution C of phenolic resin and nitrile rubber;

[0041] (3) Then, the adhesive liquid C is coated on the release paper into a thin film by a coating machine;

[0042] (4) Finally, the film is placed in an oven, heated to 60°C, and dried for 1 hour. The film is cut to obtain a film having a thickness of 100 μm.

[0043] After the preparation is completed, the high temperature reactive phenolic-nitrile adhesive film is used by the following steps:

[0044] (1) First, pre-stick the adhesive film to the desired bonding position of the substrate at room temperature. The adhesive film has a certain initial adhesion and can be used for pre-sticking positioning. The substrate is 304 stainless steel.

[0045] (2) Then hot pressing is performed at a temperature of 160° C., a pressure of 0.4 MPa, and a time of 120-180 seconds to produce a chemical cross-linking reaction, and finally cooled to room temperature to achieve a high adhesive effect.

[0046] Example 2

[0047] A high-temperature reactive phenolic-nitrile adhesive film comprises the following raw materials by weight: 40 parts of thermoplastic phenolic resin (methyl modified phenolic resin), 40 parts of nitrile rubber (Mooney viscosity is 70), 10 parts of petroleum resin, 10 parts of thermosetting phenolic resin, 5 parts of hexamethylenetetramine, 2 parts of sulfur, 2 parts of tetrabenzylthiuram disulfide, 3 parts of zinc oxide, 10 parts of magnesium oxide, 10761 parts of antioxidant and 3 parts of carbon black N550.

[0048] Prepare the high temperature reactive phenolic-nitrile film as follows:

[0049] (1) firstly cutting the phenolic resin and the nitrile rubber into suitable sizes, adding them into ethyl acetate, stirring and dissolving them, to obtain an ethyl acetate solution A of the phenolic resin and an ethyl acetate solution B of the nitrile rubber;

[0050] (2) Then, solution B and the tackifying resin, reactive resin, curing agent, vulcanizing agent, filler, antioxidant and carbon black according to claim 1 are added to solution A in a certain proportion, and an appropriate amount of ethyl acetate is added to adjust the solid content of the solution to 25-45%, and the mixture is stirred until the mixture is uniformly mixed to obtain an ethyl acetate glue solution C of phenolic resin and nitrile rubber;

[0051] (3) Then, the adhesive liquid C is coated on the release paper into a thin film by a coating machine;

[0052] (4) Finally, the film is placed in an oven and heated to 60°C. After drying for 1 hour, the film is cut to obtain a film with a thickness of 100 μm.

[0053] After the preparation is completed, the high temperature reactive phenolic-nitrile adhesive film is used by the following steps:

[0054] (1) First, pre-stick the adhesive film to the desired bonding position of the substrate at room temperature. The adhesive film has a certain initial adhesion and can be used for pre-sticking positioning. The substrate is 304 stainless steel.

[0055] (2) Then hot pressing is performed at a temperature of 160° C., a pressure of 0.4 MPa, and a time of 120-180 seconds to produce a chemical cross-linking reaction, and finally cooled to room temperature to achieve a high adhesive effect.

[0056] Comparative Example 1

[0057] A high-temperature reactive phenolic-nitrile adhesive film comprises the following raw materials by weight: 60 parts of thermoplastic phenolic resin (methyl modified phenolic resin), 40 parts of nitrile rubber (Mooney viscosity is 70), 6 parts of hexamethylenetetramine, 1 part of sulfur, 2 parts of tetrabenzylthiuram disulfide, 2 parts of zinc oxide, 10 parts of magnesium oxide, 10760.5 parts of antioxidant, and 2 parts of carbon black N550.

[0058] Prepare the high temperature reactive phenolic-nitrile film as follows:

[0059] (1) firstly cutting the phenolic resin and the nitrile rubber into suitable sizes, adding them into ethyl acetate, stirring and dissolving them, to obtain an ethyl acetate solution A of the phenolic resin and an ethyl acetate solution B of the nitrile rubber;

[0060] (2) Then, solution B and the tackifying resin, reactive resin, curing agent, vulcanizing agent, filler, antioxidant and carbon black according to claim 1 are added to solution A in a certain proportion, and an appropriate amount of ethyl acetate is added to adjust the solid content of the solution to 25-45%, and the mixture is stirred until the mixture is uniformly mixed to obtain an ethyl acetate glue solution C of phenolic resin and nitrile rubber;

[0061] (3) Then, the adhesive liquid C is coated on the release paper into a thin film by a coating machine;

[0062] (4) Finally, the film is placed in an oven and heated to 60°C. After drying for 1 hour, the film is cut to obtain a film having a thickness of 100 μm.

[0063] After the preparation is completed, the high temperature reactive phenolic-nitrile adhesive film is used by the following steps:

[0064] (1) First, fix the adhesive film on the desired bonding position of the substrate at room temperature. The substrate is 304 stainless steel.

[0065] (2) Then hot pressing is performed at a temperature of 160° C., a pressure of 0.4 MPa, and a time of 120-180 seconds to produce a chemical cross-linking reaction, and finally cooled to room temperature to achieve a high adhesive effect.

[0066] Comparative Example 2

[0067] A high-temperature reactive phenolic-nitrile adhesive film comprises the following raw materials by weight: 40 parts of thermoplastic phenolic resin (methyl modified phenolic resin), 60 parts of nitrile rubber (Mooney viscosity is 70), 5 parts of hexamethylenetetramine, 2 parts of sulfur, 2 parts of tetrabenzylthiuram disulfide, 3 parts of zinc oxide, 10 parts of magnesium oxide, 10761 parts of antioxidant and 3 parts of carbon black N550.

[0068] Prepare the high temperature reactive phenolic-nitrile film as follows:

[0069] (1) firstly cutting the phenolic resin and the nitrile rubber into suitable sizes, adding them into ethyl acetate, stirring and dissolving them, to obtain an ethyl acetate solution A of the phenolic resin and an ethyl acetate solution B of the nitrile rubber;

[0070] (2) Then, solution B and the tackifying resin, reactive resin, curing agent, vulcanizing agent, filler, antioxidant and carbon black according to claim 1 are added to solution A in a certain proportion, and an appropriate amount of ethyl acetate is added to adjust the solid content of the solution to 25-45%, and the mixture is stirred until the mixture is uniformly mixed to obtain an ethyl acetate glue solution C of phenolic resin and nitrile rubber;

[0071] (3) Then, the adhesive liquid C is coated on the release paper into a thin film by a coating machine;

[0072] Finally, put it into an oven, heat it to 60°C, dry it for 1 hour, and cut it to obtain a film. The thickness of the film after cutting is 100um.

[0073] After the preparation is completed, the high temperature reactive phenolic-nitrile adhesive film is used by the following steps:

[0074] (1) First, fix the adhesive film on the required bonding position of the substrate at room temperature. The substrate is made of 304 stainless steel.

[0075] (2) Then hot pressing is performed at a temperature of 160° C., a pressure of 0.4 MPa, and a time of 120-180 seconds to produce a chemical cross-linking reaction, and finally cooled to room temperature to achieve a high adhesive effect.

[0076] The present invention refers to ASTM D1002 standard to test the dynamic shear strength (rigid material against rigid material) of the adhesive films in various embodiments and comparative examples.

[0077] Table 1 Film dynamic shear strength test results (stainless steel 304 vs. stainless steel 304)

[0078] Test Examples Curing time Curing pressure Curing temperature Shear Strength Example 1 2min 0.4MPa 160℃ 16.0MPa Example 1 3min 0.4MPa 160℃ 17.6MPa Example 2 2min 0.4MPa 160℃ 15.3MPa Example 2 3min 0.4MPa 160℃ 16.9MPa Comparative Example 1 2min 0.4MPa 160℃ 6.4MPa Comparative Example 1 3min 0.4MPa 160℃ 8.0MPa Comparative Example 2 2min 0.4MPa 160℃ 5.8MPa Comparative Example 2 3min 0.4MPa 160℃ 7.3MPa

[0079] It can be seen that in Example 1, the performance of the film is the best, which solves the problem mentioned in the background technology: the harsh curing conditions of the phenolic-nitrile film, greatly shortens the curing time, and reduces the pressure required for curing, so that the same shear strength can be achieved.

[0080] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" 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 includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0081] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high temperature reactive adhesive film, characterized in that: Includes the following weight components: Phenolic resin 40-60 parts 40-60 parts of nitrile rubber 10-20 parts of tackifying resin Reactive resin 10-20 parts 3-9 parts of curing agent Vulcanizing agent 0.5-2 parts Accelerator 0.5-2 parts Filler 5-15 parts Antioxidant 0.5-1 part 1-3 parts of carbon black.

2. The high temperature reactive adhesive film according to claim 1, characterized in that: The phenolic resin is at least one of linear phenolic resin, methyl modified phenolic resin, tert-butyl modified phenolic resin and cardanol modified phenolic resin.

3. The high temperature reactive adhesive film according to claim 1, characterized in that: The nitrile rubber has a nitrile content of 30%-45% and a Mooney viscosity of 60-80.

4. The high temperature reactive adhesive film according to claim 1, characterized in that: The tackifying resin is at least one of petroleum resin, rosin resin and terpene resin.

5. The high temperature reactive adhesive film according to claim 1, characterized in that: The reactive resin is at least one of thermosetting phenolic resin, epoxy-modified phenolic resin, epoxy resin, KH550 and KH560.

6. The high temperature reactive adhesive film according to claim 1, characterized in that: The curing agent is any one of hexamethylenetetramine, paraformaldehyde and dicumyl peroxide.

7. The high temperature reactive adhesive film according to claim 1, characterized in that: The vulcanizing agent is at least one of sulfur, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, and tetrabenzylthiuram disulfide.

8. The high temperature reactive adhesive film and the preparation and use method thereof according to claim 1, characterized in that: The accelerator is at least one of 2-mercaptobenzothiazole, dibenzothiazole disulfide, N-cyclohexyl-2-benzothiazole sulfenamide, N,N-dicyclohexyl-2-benzothiazole sulfenamide, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, and tetrabenzylthiuram disulfide.

9. The high temperature reactive adhesive film according to claim 1, characterized in that: The filler is at least one of zinc oxide, magnesium oxide, barium sulfate, talcum powder and silicon dioxide.

10. A method for preparing a high temperature reactive adhesive film, for preparing any one of claims 1 to 9, characterized in that: The steps include: S1, cutting the phenolic resin and the nitrile rubber into appropriate sizes, adding them into ethyl acetate, stirring and dissolving them to obtain an ethyl acetate solution A of the phenolic resin and an ethyl acetate solution B of the nitrile rubber; S2, adding solution B and the tackifying resin, reactive resin, curing agent, vulcanizing agent, filler, antioxidant and carbon black as described in claim 1 to solution A in a certain proportion, adding an appropriate amount of ethyl acetate, adjusting the solid content of the solution to 25-45%, stirring until the mixture is uniform, and obtaining ethyl acetate glue C of phenolic resin and nitrile rubber; S3, coating the adhesive liquid C on the release paper into a thin film by a coating machine; S4, putting the film into an oven, heating it, drying it and cutting it to obtain a film.

11. The method for preparing a high temperature reactive adhesive film according to claim 10, characterized in that: In step S4, the temperature during heating is 50-90°C.

12. The method for preparing a high temperature reactive adhesive film according to claim 10, characterized in that: In step S4, the drying time is 0.5-3 hours.

13. The method for preparing a high temperature reactive adhesive film according to claim 10, characterized in that: In the step S4, the thickness of the adhesive film after cutting is 25-100 μm.

14. A method for using a high temperature reactive adhesive film, for using any one of the high temperature reactive adhesive films as claimed in claims 1 to 9, characterized in that: The method comprises the following steps: pre-pasting the adhesive film at the desired bonding position of the substrate at room temperature, at which time the adhesive film has initial adhesiveness for pre-pasting positioning; then performing heat pressing under certain temperature and pressure conditions to produce a chemical cross-linking reaction, and then cooling to room temperature to maintain high adhesiveness.

15. The method for using the high temperature reactive adhesive film according to claim 14, characterized in that: The substrate is at least one of stainless steel 304, stainless steel 316, anodized aluminum, and nickel-plated aluminum.

16. The method for using the high temperature reactive adhesive film according to claim 14, characterized in that: The hot pressing temperature is 160° C., the hot pressing pressure is 0.4-3 MPa, and the pre-lamination time is 120-180 seconds.