Corrosion-resistant conductive adhesion-reducing tape and method of making same

Abstract

The application belongs to the technical field of adhesives, and particularly relates to a corrosion-resistant power-on adhesion-reducing adhesive tape and a preparation method thereof. The power-on adhesion-reducing adhesive tape comprises an adhesive layer and release layers attached to two sides of the adhesive layer. The adhesive layer is prepared by using an initiator to initiate free radical polymerization of soft monomers, hard monomers and functional monomers. The functional monomers can act as crosslinking agents, so that the prepared acrylate adhesive has a high crosslinking density, and the structure of the adhesive layer is more compact, which can effectively prevent the penetration of corrosive media. In addition, the functional monomers have a triazine-perfluoro alternating connection structure. The presence of the triazine ring can make the adhesive layer have more excellent high-temperature resistance. The presence of the perfluoro segment can make the molecular chain have a high hydrophobic effect, and can form a hydrophobic layer on the surface of the adhesive layer, thereby greatly improving the corrosion resistance of the power-on adhesion-reducing adhesive tape.

Description

Technical Field

[0001] This invention belongs to the field of adhesive technology, specifically relating to a corrosion-resistant, electrically conductive, and non-sticky adhesive tape and its preparation method. Background Technology

[0002] As a smart functional material, electrically conductive adhesive tape achieves dynamic control of adhesion through electric field modulation, and has become a core technology for non-destructive disassembly and reuse of devices in fields such as precision electronics, new energy batteries, and aerospace. Its technical principle is based on the electro-responsive characteristics of polymer materials: when conductive fillers or ionic electrolytes are embedded within the tape, charge migration after energization induces changes in the microstructure of the adhesive layer, such as the breakage of cross-linked networks and the recombination of polar groups due to ion migration, thereby transforming the adhesive layer from a high-viscosity state to a low-viscosity state.

[0003] Despite the functional breakthroughs achieved by electrically conductive non-stick tapes, they face severe corrosion challenges in practical applications, especially in highly corrosive environments such as new energy batteries, marine equipment, and chemical pipelines. Corrosion resistance has become a key bottleneck restricting their lifespan and reliability. Therefore, developing electrically conductive non-stick tapes with corrosion resistance has gradually become a research hotspot. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a corrosion-resistant, electrically conductive, and non-sticky adhesive tape and its preparation method.

[0005] In a first aspect, the present invention provides a corrosion-resistant, electrically conductive, non-sticky tape, comprising an adhesive layer and release layers attached to both sides of the adhesive layer;

[0006] The adhesive layer is made from the following raw materials measured in parts by weight:

[0007] 35-50 parts of soft monomer;

[0008] 10-15 parts of hard monomer;

[0009] 1-3.5 parts of modified monomer;

[0010] 1-2 parts of ionic liquid monomer;

[0011] Initiator 0.3-0.6 parts;

[0012] 60-80 parts of polymerization medium;

[0013] 3-5 parts of conductive additive;

[0014] 0.5-1 part lithium metal salt.

[0015] As a preferred embodiment of the present invention, the soft monomer is butyl acrylate or isooctyl acrylate; the hard monomer is methyl methacrylate or butyl methacrylate; the ionic liquid monomer is 1-vinyl-3-methylimidazolium dinitrile or 1-allyl-3-vinylimidazolium dinitrile; the initiator is azobisisobutyronitrile or azobisisoheptanenitrile; the polymerization medium is ethyl acetate; the conductive additive is carbon nanotube or graphene; and the lithium metal salt is any one of lithium itaconic acid, lithium tetrafluoroborate, or lithium bis(oxalato)borate.

[0016] As a preferred embodiment of the present invention, the modified monomer is prepared by the following method:

[0017] 2,4-Diamino-6-diallylamino-1,3,5-triazine and N,N-dimethylformamide were added to a nitrogen-filled polymerization reactor and stirred until a homogeneous reaction solution was formed. Then, the chain extender was added to the polymerization reactor. After the addition was complete, the reactor was heated to 70-80°C and stirred at this temperature for 6-9 hours. Then, an acid-binding agent was added. After the addition was complete, stirring was continued for 8-16 hours. The solvent was evaporated to remove the product, and the product was collected. The modified monomer was obtained through a purification process.

[0018] As a preferred embodiment of the present invention, the molar ratio of 2,4-diamino-6-diallylamino-1,3,5-triazine to the chain extender is 1:1.

[0019] As a preferred embodiment of the present invention, the chain extender is prepared by the following method:

[0020] Perfluorodiol compounds and tetrahydrofuran were added to a reaction vessel, nitrogen gas was introduced for protection, stirring was started, and after mixing was uniform, the mixture was placed in an ice bath environment. Then, halogenated modification reagents and pyridine were added to the reaction vessel. After the addition was complete, the vessel was removed from the ice bath and stirred continuously at a temperature of 30-40℃ for 3-6 hours. The solvent was evaporated to remove the product, which was then collected and purified to obtain the chain extender.

[0021] As a preferred embodiment of the present invention, the perfluorodiol compound is any one of 1H,1H,2H,3H,3H-perfluorononane-1,2-diol, 1H,1H,9H,9H-perfluoro-1,9-nonanediol, or hexadecylfluoro-1,10-decanediol.

[0022] As a preferred embodiment of the present invention, the halogenated modifying agent is any one of chloroacetyl chloride, bromoacetyl bromide, or 4-bromobutyryl chloride.

[0023] As a preferred embodiment of the present invention, the molar ratio of the perfluorodiol compound and the halogenated modifying agent is 1:2.

[0024] As a preferred embodiment of the present invention, the acid-binding agent is an aqueous solution of sodium hydroxide with a mass fraction of 10-20%.

[0025] It should be noted that in the above technical solution, firstly, perfluorodiol compounds are halogenated by using a halogenating agent. The active acyl halide groups and hydroxyl substituents in their structures undergo a condensation reaction, and the ratio of the two is controlled to obtain a perfluorinated derivative containing two equivalent active halogen substituents, i.e., a chain extender. Then, under the action of an acid-binding agent, the two equivalent halogen substituents in its structure undergo a continuous substitution reaction with the amino substituents in the structure of 2,4-diamino-6-diallylamino-1,3,5-triazine, thereby obtaining a modified monomer with a triazine-perfluorine alternating linkage structure.

[0026] A second aspect of the present invention provides a method for preparing a corrosion-resistant, electrically conductive, anti-adhesive tape, comprising the following steps:

[0027] Step 1: Weigh out each ingredient according to the specified weight proportions and set aside.

[0028] The second step involves adding the soft monomer, hard monomer, ionic liquid monomer, modified monomer, and initiator to the polymerization medium, starting the stirring, and mixing evenly. Then, heating is started and the temperature is maintained at 70-75℃. After stirring at this temperature for 6-12 hours, the temperature is reduced to 30-40℃. Then, lithium metal salt and conductive additives are added, and stirring is continued for 20-30 minutes to obtain the adhesive layer precursor.

[0029] The third step is to evenly coat the adhesive layer precursor material onto one side of the release film. After coating, place it in a temperature environment of 70-80℃ for 5-10 minutes to form an adhesive layer. Then, attach another layer of release film to the coated surface to obtain the electrostatically conductive anti-adhesive tape.

[0030] It should be noted that, under the action of an initiator, the unsaturated alkenyl functional groups in the structures of soft monomers, hard monomers, ionic liquid monomers, and modified monomers can undergo free radical polymerization. Since the modified monomer structure contains a large number of unsaturated alkenyl functional groups, it can act as a crosslinking agent and can produce highly crosslinked acrylate adhesives.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] This invention prepares functional monomers as one of the raw materials for acrylate adhesives. First, due to the large number of unsaturated alkenyl groups in its structure, cross-linking occurs during free radical polymerization, resulting in a high cross-linking density in the prepared acrylate adhesive. The increased cross-linking density of the molecular chains makes the adhesive layer structure more compact, effectively preventing corrosive media from penetrating into the adhesive layer. In addition, the functional monomers have a triazine-perfluorine alternating linkage structure. The presence of triazine rings improves the stability of the adhesive molecular chains, exhibiting superior high-temperature resistance. The presence of perfluorine segments makes the molecular chains highly hydrophobic and forms a hydrophobic layer on the adhesive layer surface, further preventing the retention and penetration of corrosive media, thereby significantly improving the corrosion resistance of the electrically conductive anti-adhesive tape. Attached Figure Description

[0033] 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.

[0034] Figure 1 Infrared analysis test results for the modified monomer. Detailed Implementation

[0035] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0036] Example 1:

[0037] This embodiment provides a corrosion-resistant, electrically conductive, non-sticky tape, including an adhesive layer and release layers attached to both sides of the adhesive layer;

[0038] The adhesive layer is made from the following raw materials measured in parts by weight:

[0039] 35 parts butyl acrylate;

[0040] 10 parts of methyl methacrylate;

[0041] One part of the modified monomer;

[0042] 1 part of 1-vinyl-3-methylimidazolium dinitrile ammonium salt;

[0043] 0.3 parts of azobisisobutyronitrile;

[0044] 60 parts of ethyl acetate;

[0045] Three parts of carbon nanotubes;

[0046] 0.5 parts of lithium tetrafluoroborate;

[0047] The method for preparing the electrically conductive anti-adhesive tape includes the following steps:

[0048] Step 1: Weigh out each ingredient according to the specified weight proportions and set aside.

[0049] Step 2: Add butyl acrylate, methyl methacrylate, 1-vinyl-3-methylimidazolium dinitrile, modified monomer and azobisisobutyronitrile to ethyl acetate, start stirring, mix evenly, start heating, maintain the temperature at 75℃, keep stirring at this temperature for 9 hours, then reduce the temperature to 35℃, then add lithium tetrafluoroborate and carbon nanotubes, and continue stirring for 30 minutes to obtain the adhesive layer precursor material.

[0050] The third step is to evenly coat the adhesive layer precursor material onto one side of the release film. After coating, place it in a 75°C environment for 10 minutes to form an adhesive layer. Control the thickness of the adhesive layer to 50μm. Then attach another release film to the coated surface to obtain the electrostatically conductive anti-adhesive tape.

[0051] The modified monomers were prepared using the following methods:

[0052] Step 1: Add 0.8g of 1H,1H,9H,9H-perfluoro-1,9-nonanediol and tetrahydrofuran to the reaction vessel, purge with nitrogen for protection, start stirring, mix thoroughly, and place in an ice bath environment. Then add 0.44g of chloroacetyl chloride and 0.1g of pyridine to the reaction vessel. After the addition is complete, remove from the ice bath and stir continuously at 35°C for 4 hours. Evaporate to remove the solvent, collect the product, and purify to obtain the chain extender.

[0053] Step 2: Add 0.5g of 2,4-diamino-6-diallylamino-1,3,5-triazine and N,N-dimethylformamide to a nitrogen-filled polymerization reactor. Start stirring until a homogeneous reaction solution is formed. Then add 1.37g of chain extender to the polymerization reactor. After the addition is complete, heat the reactor and control the temperature at 75℃. Keep stirring at this temperature for 8 hours. Then add 4mL of 10% sodium hydroxide aqueous solution. After the addition is complete, continue stirring for 12 hours. Evaporate to remove the solvent, collect the product, and obtain the modified monomer through purification.

[0054] Figure 1 The image shows the infrared analysis results of the modified monomer, with 3371 cm⁻¹. -1 and 3284cm -1 The characteristic absorption peak appearing at 1737 cm⁻¹ belongs to the characteristic absorption peak of NH. -1 The characteristic absorption peak appearing at 1589 cm⁻¹ is attributed to the C=O characteristic absorption peak of the ester group.-1 The characteristic absorption peak appearing at 1296 cm⁻¹ is attributed to the C=N characteristic absorption peak of the triazine ring. -1 The characteristic absorption peak appearing at this point belongs to the CF characteristic absorption peak.

[0055] Example 2:

[0056] This embodiment provides a corrosion-resistant, electrically conductive, non-sticky tape, including an adhesive layer and release layers attached to both sides of the adhesive layer;

[0057] The adhesive layer is made from the following raw materials measured in parts by weight:

[0058] 40 parts butyl acrylate;

[0059] 12 parts of methyl methacrylate;

[0060] 3 parts of modified monomer;

[0061] 1.5 parts of 1-vinyl-3-methylimidazolium dinitrile ammonium salt;

[0062] 0.5 parts of azobisisobutyronitrile;

[0063] 70 parts of ethyl acetate;

[0064] 4 parts of carbon nanotubes;

[0065] 0.8 parts of lithium tetrafluoroborate;

[0066] The method for preparing the electrically conductive anti-adhesive tape includes the following steps:

[0067] Step 1: Weigh out each ingredient according to the specified weight proportions and set aside.

[0068] Step 2: Add butyl acrylate, methyl methacrylate, 1-vinyl-3-methylimidazolium dinitrile, modified monomer and azobisisobutyronitrile to ethyl acetate, start stirring, mix evenly, start heating, maintain the temperature at 75℃, keep stirring at this temperature for 9 hours, then reduce the temperature to 35℃, then add lithium tetrafluoroborate and carbon nanotubes, and continue stirring for 30 minutes to obtain the adhesive layer precursor material.

[0069] The third step is to evenly coat the adhesive layer precursor material onto one side of the release film. After coating, place it in a 75°C environment for 10 minutes to form an adhesive layer. Control the thickness of the adhesive layer to 50μm. Then attach another release film to the coated surface to obtain the electrostatically conductive anti-adhesive tape.

[0070] The preparation method of the modified monomer is the same as that in Example 1.

[0071] Example 3:

[0072] This embodiment provides a corrosion-resistant, electrically conductive, non-sticky tape, including an adhesive layer and release layers attached to both sides of the adhesive layer;

[0073] The adhesive layer is made from the following raw materials measured in parts by weight:

[0074] 50 parts butyl acrylate;

[0075] 15 parts of methyl methacrylate;

[0076] 3.5 parts of modified monomer;

[0077] 2 parts of 1-vinyl-3-methylimidazolium dinitrile ammonium salt;

[0078] 0.6 parts of azobisisobutyronitrile;

[0079] 80 parts of ethyl acetate;

[0080] 5 parts of carbon nanotubes;

[0081] One part of lithium tetrafluoroborate;

[0082] The method for preparing the electrically conductive anti-adhesive tape includes the following steps:

[0083] Step 1: Weigh out each ingredient according to the specified weight proportions and set aside.

[0084] Step 2: Add butyl acrylate, methyl methacrylate, 1-vinyl-3-methylimidazolium dinitrile, modified monomer and azobisisobutyronitrile to ethyl acetate, start stirring, mix evenly, start heating, maintain the temperature at 75℃, keep stirring at this temperature for 9 hours, then reduce the temperature to 35℃, then add lithium tetrafluoroborate and carbon nanotubes, and continue stirring for 30 minutes to obtain the adhesive layer precursor material.

[0085] The third step is to evenly coat the adhesive layer precursor material onto one side of the release film. After coating, place it in a 75°C environment for 10 minutes to form an adhesive layer. Control the thickness of the adhesive layer to 50μm. Then attach another release film to the coated surface to obtain the electrostatically conductive anti-adhesive tape.

[0086] The preparation method of the modified monomer is the same as that in Example 1.

[0087] Comparative Example 1

[0088] The difference between this comparative example and Example 2 is that the modified monomer is replaced with 2,4-diamino-6-diallylamino-1,3,5-triazine, otherwise they are the same.

[0089] Comparative Example 2

[0090] The difference between this comparative example and Example 1 is that no modified monomer is added; all other aspects are the same.

[0091] The performance of the electrically conductive anti-adhesion tapes provided in the above embodiments and comparative examples was tested using the following methods:

[0092] (1) According to standard GB / T 2792-2014, the tape sample was attached to a stainless steel plate and the adhesion performance was tested;

[0093] (2) Attach the tape sample to a stainless steel plate, then bake it in an oven at 150°C for 4 hours, and then peel off the tape by heat. Observe whether there is any residue and evaluate the high temperature resistance of the tape.

[0094] (3) Attach the tape sample to the surface of aluminum foil, then immerse it in lithium battery electrolyte at a temperature of 80°C for 24 hours, and then take it out to observe the adhesive layer phenomenon and evaluate the corrosion resistance of the tape.

[0095] The performance test data above are shown in Table 1.

[0096] Table 1 Performance Test Results

[0097]

[0098] As can be seen from the above, the electrically conductive anti-adhesive tape prepared in the embodiments of the present invention has good adhesion, high temperature resistance, and corrosion resistance. Replacing the modified monomer with 2,4-diamino-6-diallylamino-1,3,5-triazine results in the absence of highly hydrophobic perfluorinated chains in the adhesive molecular chain, leading to insufficient hydrophobicity of the tape surface and thus reduced corrosion resistance. Furthermore, it can be observed that the presence of the crosslinking agent also has a positive effect on the adhesion performance of the adhesive layer. This is because increasing the crosslinking density increases the cohesive energy of the adhesive, thereby exhibiting higher adhesion performance.

[0099] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention, including the best mode, and also to enable any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A corrosion-resistant, electrically-conductive, adhesion-reducing tape, characterized by, The adhesive layer is prepared by using the following raw materials in the amount of parts by weight: The adhesive layer is prepared by using the following raw materials in the amount of parts by weight: Soft monomer 35-50 parts; Hard monomer 10-15 parts; Modified monomer 1-3.5 parts; Ionic liquid monomer 1-2 parts; Initiator 0.3-0.6 parts; Polymerization medium 60-80 parts; Conductive additive 3-5 parts; Lithium metal salt 0.5-1 part; The soft monomer is butyl acrylate or isooctyl acrylate; the hard monomer is methyl methacrylate or butyl methacrylate; the ionic liquid monomer is 1-vinyl-3-methyl imidazole dicyanamide salt or 1-allyl-3-vinyl imidazole dicyanamide salt; the initiator is azobisdimethyl isobutyronitrile or azobisdimethyl isohexyl nitrile; the polymerization medium is ethyl acetate; the conductive additive is carbon nanotube or graphene; the lithium metal salt is any one of lithium itaconate, lithium tetrafluoroborate or lithium bisoxalate borate; The modified monomer is prepared by the following method: 2,4-diamino-6-diallyl amino-1,3,5-triazine and N,N-dimethyl formamide are added to a nitrogen-filled polymerization kettle, stirring is started, after a uniform reaction liquid is formed, a chain extension agent is added to the polymerization kettle, heating is started, the temperature is controlled at 70-80℃, after 6-9h of temperature control and stirring at this temperature, an acid binding agent is added, after the addition is completed, stirring is continued for 8-16h, the solvent is evaporated and removed, the product is collected, and the modified monomer is obtained through a purification process; The chain extension agent is prepared by the following method: Perfluorinated diol compound and tetrahydrofuran are added to a reaction kettle, nitrogen is introduced for protection, stirring is started, after mixing is uniform, the reaction kettle is placed in an ice bath environment, halogenated modification reagent and pyridine are then added to the reaction kettle, after the addition is completed, the ice bath is removed, stirring is continued at a temperature of 30-40℃ for 3-6h, the solvent is evaporated and removed, the product is collected, and the chain extension agent is obtained through a purification process; The perfluorinated diol compound is any one of 1H,1H,2H,3H,3H-perfluorononane-1,2-diol, 1H,1H,9H,9H-perfluoro-1,9-nonanediol or hexadecafluoro-1,10-decanediol; The halogenated modification reagent is any one of chloroacetyl chloride, bromoacetyl bromide or 4-bromobutyryl chloride.

2. The corrosion-resistant, electrically-conductive adhesive tape of claim 1, wherein, The molar ratio of 2,4-diamino-6-diallyl amino-1,3,5-triazine to the chain extension agent is 1:

1.

3. The corrosion resistant, electrically conductive adhesive tape of claim 1, wherein, The molar ratio of the perfluorinated diol compound to the halogenated modification reagent is 1:

2.

4. The corrosion resistant, electrically conductive adhesive tape of claim 1, wherein, The acid binding agent is sodium hydroxide aqueous solution with a mass fraction of 10-20%.

5. A method of preparing the corrosion-resistant, electrically-conductive, adhesion-reducing tape of claim 1, wherein, The method comprises the following steps: First step, each raw material is weighed according to the amount of parts by weight and is prepared for use; Second step, the soft monomer, the hard monomer, the ionic liquid monomer, the modified monomer and the initiator are added to the polymerization medium, stirring is started, after mixing is uniform, heating is started, the temperature is maintained at 70-75℃, after 6-12h of temperature control and stirring, the temperature is reduced to 30-40℃, then the lithium metal salt and the conductive additive are added, stirring is continued for 20-30min, and the adhesive layer precursor is obtained. Third step, the adhesive layer precursor is evenly coated on one side of the release film, after coating, it is placed in a temperature environment of 70-80℃ for 5-10min, forming the adhesive layer, then another layer of release film is attached on the coated surface, and the electrically conductive adhesive tape is obtained.

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