CN115820169B

CN115820169B - Adhesive, adhesive tape, preparation method of adhesive and adhesive tape and electrochemical device

Info

Publication number: CN115820169B
Application number: CN202210016169.0A
Authority: CN
Inventors: 祁少伟; 陆阳; 杨献伟; 靳超; 任苗苗; 齐晨; 叶永煌
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-01-07
Filing date: 2022-01-07
Publication date: 2024-03-26
Anticipated expiration: 2042-01-07
Also published as: CN115820169A

Abstract

The present disclosure relates to the field of lithium-ion power batteries, and more particularly, to a binder, an adhesive tape, a method of preparing the same, and an electrochemical device including the adhesive tape. The binder at least comprises a supermolecular compound, a cationic additive, an adhesive and a curing agent, wherein the supermolecular compound is calixarene. The adhesive acts on the polyethylene terephthalate film subjected to hydroxylation treatment, and the adhesion with the polyethylene terephthalate film is improved through a crosslinking reaction. Meanwhile, the supermolecular compound has high-temperature stability and reduced hydrophilicity after being coordinated with the cationic additive, so that the adhesive can maintain the adhesive property in a high-temperature environment and a humid environment for a long time.

Description

Adhesive, adhesive tape, preparation method of adhesive and adhesive tape and electrochemical device

Technical Field

The present disclosure relates to the field of lithium-ion power batteries, and more particularly, to a binder, an adhesive tape, a method of preparing the same, and an electrochemical device including the adhesive tape in a power battery.

Background

Compared with the traditional secondary batteries such as lead-acid batteries, nickel-hydrogen batteries and the like, the lithium ion power battery has the advantages of high energy density, high output voltage, low self-discharge, no memory effect, environmental friendliness and the like, and is widely applied and developed. In the process of assembling, in order to ensure the insulativity of the lithium ion power battery shell, the surface of the battery shell needs to be coated with an insulating layer, and then the large surface and the side surface of the battery of the coating film are coated with an adhesive for connecting with a heat insulation pad and a side plate of the module. The failure of the insulating film and the adhesive can seriously affect the stability and the safety of the battery, and hidden trouble is brought to the daily life of people.

Disclosure of Invention

After the lithium ion power battery is assembled, the temperature of the battery increases due to the discharge of the battery and the like. The insulating film and the adhesive wrapped on the surface of the battery can fail in advance after being in a high-temperature environment for a long time. In addition, the lithium ion battery inevitably works in a humid environment, and in the humid environment, moisture gradually permeates into a bonding interface between the batteries, and bonding failure of the lithium ion battery is also caused in advance. In order to solve the above problems, the present disclosure provides a binder, an adhesive tape, a method of preparing the same, and an electrochemical device including the adhesive tape, which can maintain adhesion under high temperature and high humidity environments, improve structural stability of a power battery, and improve safety of the battery.

In a first aspect, the present disclosure provides a binder comprising a supramolecular compound that is a calixarene having a structure represented by the following formula (1),

wherein R is independently selected from alkyl, ester, ketone, ether, carboxyl, sulfo or amide groups;

n is selected from integers greater than 3.

In the technical scheme of the embodiment of the disclosure, calixarene is a cyclic oligomer obtained by methylene bridging phenol units, and has better high-temperature stability. Different functional groups are respectively introduced into the upper edge and the lower edge of the calixarene structure, so that the chemical reaction or coordination of the calixarene with organic molecules, cations and the like is realized. Specifically, the upper edge of the calixarene structure is a substituent connected with a benzene ring, and the substituent can be subjected to chemical reaction with an organic molecule or form a complex through hydrogen bond, van der Waals force, electrostatic action and steric hindrance, so that the cohesiveness of the complex is improved. The lower edge of the calixarene structure is hydrophilic phenolic hydroxyl, and after the hydrophilic phenolic hydroxyl and a cation or a cation compound form a coordination compound through the cation-pi action and pi-pi stacking action, the swelling failure of the binder caused by water molecules can be reduced. Therefore, the calixarene can improve the high temperature resistance and the humidity resistance of the adhesive.

In some embodiments of the present disclosure, the R group of the supramolecular compound is an alkyl group; alternatively, t-butyl.

In the technical scheme of the embodiment of the disclosure, the R group type at the upper edge of the supermolecular compound calixarene can influence the bonding strength of the calixarene, the adhesive and the curing agent, and the tertiary butyl group has higher steric hindrance, so that the adhesive has stable bonding effect.

In some embodiments of the present disclosure, n of the supramolecular compound is an integer greater than 3 and less than or equal to 6; alternatively, n is 4.

In the technical scheme of the embodiment of the disclosure, the increase or decrease of the number of supermolecule groups can lead to the decrease of the cohesive force of the adhesive under the high-temperature and high-humidity environment. When n is 4, that is, the supermolecular compound is calix [4] arene, the adhesive shows better adhesive force in high temperature and high humidity environment.

In some embodiments of the present disclosure, the mass fraction of the supramolecular compound in the binder is 15% -25%; alternatively, 17% -23%; still alternatively, 20%.

In the technical scheme of the embodiment of the disclosure, the long-term stability of the binder in a high-temperature and high-humidity environment can be obviously reduced when the content of the supermolecular compound is too high or too low. When the mass fraction of the supermolecular compound is in a proper range, the adhesive has better initial adhesion and long-term stability in a high-temperature and high-humidity environment.

In some embodiments of the present disclosure, the binder further comprises one or more of a cationic additive, an adhesive, a curing agent, a solvent.

In the technical scheme of the embodiment of the disclosure, the cationic additive can coordinate with the hydrophilic phenolic hydroxyl at the lower edge of the calixarene, so that the hydrophilicity of the calixarene is reduced, water molecules are difficult to diffuse in the adhesive, and the adhesive still has good adhesive effect in a humid environment. The adhesive can be combined with the substituent group on the upper edge of calixarene through hydrogen bond, van der Waals force or electrostatic action, so that the bonding effect of the adhesive is enhanced. The curing agent can react with the polyethylene terephthalate film (PET film), the substituent group of the upper edge of the calixarene and the adhesive, and can also form a complex with the substituent group of the upper edge of the calixarene through steric hindrance, so that the PET film, the calixarene and the adhesive are better connected. The solvent can better disperse each component uniformly, and each component is dissolved in the solvent, so that the coating performance of the adhesive is improved.

In some embodiments of the present disclosure, the cation of the cationic additive is selected from a metal cation or an organic cation; optionally, the cation is Li ⁺ 、Na ⁺ 、K ⁺ 、NH ₄ ⁺ One or more of the following; still optionally, the cation is Li ⁺ 。

In the technical scheme of the embodiment of the disclosure, the cationic additive mainly plays a role in coordinating with the hydroxyl at the lower edge of calixarene, so that the hydrophilicity of the hydroxyl is reduced, and the stability of the adhesive in a humid environment is further improved.

In some embodiments of the present disclosure, the adhesive is one or more of polyacrylic acid, polyurethane, epoxy, polyimide; alternatively, polyacrylic acid.

In the technical scheme of the embodiment of the disclosure, the adhesive is selected according to the bonding performance of the adhesive and the reactivity of the adhesive with the supermolecular compound and the curing agent. The upper edge substituent groups of the polyacrylic acid and the supermolecular compound are combined through hydrogen bonds, van der Waals force or electrostatic action, so that the adhesive can keep the adhesive property under the high-temperature and high-humidity environment.

In some embodiments of the present disclosure, the curing agent is one or more of a mono-isocyanate, a di-isocyanate, and a polyisocyanate; alternatively, a diisocyanate.

In the technical scheme of the embodiment of the disclosure, the isocyanate groups in isocyanate can react with the terminal hydroxyl groups on the PET film, the upper edge substituent groups of the supermolecular compound and the hydroxyl groups of the adhesive, and can also form a complex with the upper edge substituent groups of the supermolecular compound through steric hindrance, so that good connection effect is achieved.

In some embodiments of the present disclosure, the solvent comprises one or more of carbon tetrachloride, ethyl acetate, methyl formate, ethanol, toluene; optionally, the solvent is toluene.

In the technical scheme of the embodiment of the disclosure, the selected solvent can enable the supermolecular compound, the curing agent, the adhesive and the cationic additive to form a uniformly dispersed system, so that the coating performance of the adhesive is improved, and the adhesive and the surface of the matrix film are facilitated to react.

In a second aspect, the present disclosure provides the use of the adhesive in the preparation of a tape.

In a third aspect, the present disclosure provides an adhesive tape characterized in that the adhesive tape comprises an adhesive and a matrix as in the present disclosure.

In some embodiments of the present disclosure, the substrate is a hydroxylated PET film.

By introducing hydroxyl functional groups on the surface of the matrix film, the reactivity of the film surface can be improved, and favorable conditions are created for the adhesion of the binder and the PET film.

In a fourth aspect, the present disclosure provides a method for preparing an adhesive tape according to the present disclosure, the method comprising the steps of:

mixing a supermolecular compound, a cationic additive, an adhesive, a curing agent and a solvent to obtain a binder, and coating the obtained binder on at least part of the surface of the PET film.

In some embodiments of the present disclosure, the PET film is subjected to a hydroxylation treatment, the hydroxylating agent being 98 mass% H ₂ SO ₄ Aqueous solution, piranha solution, 10 mass% FeSO ₄ 30% by mass of H ₂ O ₂ One or more of the aqueous solutions, optionally a piranha solution; the adhesive is applied at a thickness of 50-100 μm, alternatively 50 μm.

In the technical scheme of the embodiment of the disclosure, hydroxyl is introduced under the acidic condition, so that the damage to ester bonds in the polymer film can be avoided; the reasonable coating thickness can improve the binding force between the PET film and the binder, and is also beneficial to improving the high temperature resistance and the moisture resistance of the adhesive tape.

In a fifth aspect, the present disclosure provides an electrochemical device comprising a tape as described in the present disclosure.

The foregoing description is merely an overview of the technical solutions of the present disclosure, and may be implemented according to the content of the specification in order to make the technical means of the present disclosure more clearly understood, and in order to make the above and other objects, features and advantages of the present disclosure more clearly understood, the following specific embodiments of the present disclosure are specifically described.

Drawings

Fig. 1 is a fourier infrared spectrum of a PET film before and after hydroxylation.

Fig. 2 is a fourier infrared spectrum of the hydroxylated PET film before and after reaction with a curing agent.

FIG. 3 is a Fourier infrared spectrum of a tape containing calixarene and adhesive in different proportions, and a tape containing calixarene with different upper edge substituents.

Fig. 4 is a fourier infrared spectrum of an adhesive tape with or without a cationic additive.

Detailed Description

Embodiments of the technical scheme of the present disclosure will be described in detail below. The following examples are only for more clearly illustrating the technical aspects of the present disclosure, and thus are merely examples, not to limit the scope of the present disclosure.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure; the terms "comprising" and "having" and any variations thereof in the description and claims of the present disclosure and in the description of the figures above are intended to cover a non-exclusive inclusion. The terms "plurality" and "a plurality" of the present disclosure mean two and more.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present disclosure. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

For simplicity, only a few numerical ranges are explicitly disclosed herein. However, any lower limit may be combined with any upper limit to form a range not explicitly recited; and any lower limit may be combined with any other lower limit to form a range not explicitly recited, and any upper limit may be combined with any other upper limit to form a range not explicitly recited. Furthermore, each point or individual value between the endpoints of the range is included within the range, although not explicitly recited. Thus, each point or individual value may be combined as a lower or upper limit on itself with any other point or individual value or with other lower or upper limit to form a range that is not explicitly recited.

The term optionally refers to embodiments of the invention that may provide certain benefits in certain circumstances. However, other embodiments may be optional under the same or other circumstances. In addition, recitation of one or more alternative embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

"high temperature" in the present disclosure means a temperature higher than the normal operating temperature of the battery, and is generally considered to be a high temperature higher than 35 ℃.

"high temperature" in the present disclosure means higher than the normal operating humidity of the battery, and it is generally considered that 95% -100% humidity is high humidity.

At present, a lithium ion power battery is a main energy source of new energy automobile power. In the process of assembling the lithium ion power battery, in order to ensure insulativity, an insulating film needs to be coated on the surface of the battery, and an adhesive is coated on the surface of the insulating film for bonding with other components of the power battery. Because the power battery is usually in a high-temperature and high-humidity environment in the use process, the insulating film coated on the surface of the battery shell is easy to generate interface delamination with the adhesive layer, so that the adhesive property is reduced sharply. In particular to a common polyethylene terephthalate film (PET film), the molecular chain has no hydrophilic group, and the molecular chain has high rigidity and crystallization capability, has poor compatibility with most polymers, and is more likely to cause failure with the adhesive. Failure of the PET film and the adhesive can seriously affect the safety of the battery, which has become an important limiting factor for the application of the adhesive in the field of bonding of power batteries.

In order to solve the above-described problems, the present inventors have conducted intensive studies and found that an adhesive can be provided. The binder comprises a supermolecular compound which is a cyclic oligomer obtained by bridging phenol units with methylene, also known as calixarene, and has high temperature stability. The upper edge of the calixarene is a substituent group connected with a benzene ring, the substituent group can be combined with the adhesive through hydrogen bond, van der Waals force or electrostatic action, and can be subjected to chemical reaction with a curing agent or form a complex through steric hindrance, so that the PET film and the adhesive can have better adhesive force in an environment with increased temperature. Meanwhile, the lower edge of the calixarene is hydrophilic phenolic hydroxyl, and after the coordination compound is formed with the cationic additive, the swelling failure of the adhesive caused by water molecules can be reduced. The adhesive at least comprises a supermolecular compound, a cationic additive, an adhesive, a curing agent and a solvent, acts on the hydroxylated PET film, can achieve the effects of high temperature resistance and high humidity resistance, and improves the structural stability and the safety of the power battery.

The adhesive and the adhesive tape disclosed by the embodiment of the disclosure can be used for any scene needing bonding or fixing in a battery, including monomer-monomer bonding, monomer-module bonding, monomer-battery pack bonding and module-battery pack bonding; the battery can be a hard shell battery or a soft package battery; in addition, the adhesive can be bonded with parts such as a heat insulation pad, a side plate and the like; the adhesive and the adhesive tape disclosed by the embodiment of the disclosure can act on a metal surface or a plastic surface; the adhesive tape disclosed by the embodiment of the disclosure can be provided with the adhesive on both sides or one side, or other adhesives are used on the other side; the bonding site may be the whole surface, or may have one or several points.

The electrochemical devices disclosed in the embodiments of the present disclosure may be used in, but are not limited to, electrical devices for vehicles, ships, or aircraft.

Adhesive agent

According to one embodiment of the present disclosure, there is provided a binder comprising a supramolecular compound which is a calixarene having a structure represented by the following formula (1),

n is selected from integers greater than 3.

The term "alkyl" refers to a saturated aliphatic hydrocarbon group which is a fully saturated branched or unbranched hydrocarbon group comprising 1 to 20 carbon atoms. Alkyl may particularly refer to hydrocarbon moieties having 1 to 16 carbon atoms, 1 to 10 carbon atoms, 1 to 7 carbon atoms, or 1 to 4 carbon atoms. Representative examples of alkyl groups include, but are not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, sec-butyl, n-pentyl, 1-dimethylpropyl, 1, 2-dimethylpropyl, 2-dimethylpropyl, 1-ethylpropyl, 2-methylbutyl, 3-methylbutyl, n-hexyl, 1-ethyl-2-methylpropyl, 1, 2-trimethylpropyl, 1-dimethylbutyl, 1, 2-dimethylbutyl, 2-dimethylbutyl, 1, 3-dimethylbutyl, 2-ethylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 2, 3-dimethylbutyl, n-heptyl, 2-methylhexyl 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 2, 3-dimethylpentyl, 2, 4-dimethylpentyl, 2-dimethylpentyl, 3-dimethylpentyl, 2-ethylpentyl, 3-ethylpentyl, n-octyl, 2, 3-dimethylhexyl, 2, 4-dimethylhexyl, 2, 5-dimethylhexyl, 2-dimethylhexyl, 3-dimethylhexyl, 4-dimethylhexyl, 2-ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 2-methyl-2-ethylpentyl, 2-methyl-3-ethylpentyl, n-nonyl, 2-methyl-2-ethylhexyl, 2-methyl-3-ethylhexyl, 2, 2-diethylpentyl, n-decyl, 3-diethylhexyl, 2-diethylhexyl, and various branched isomers thereof, and the like. The alkyl group may be substituted or unsubstituted, and when substituted, the substituent may be substituted at any useful point of attachment including, but not limited to, one or more groups independently selected from alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halogen, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, carboxy, carboxylate, and the like.

The term "ester group" means-C (O) OR ₁ Wherein R is ₁ Is a non-hydrogen group and specifically includes, but is not limited to, substituents independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halogen, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, and the like.

The term "keto" refers to-CO-R ₂ Wherein R is ₂ Substituents include, but are not limited to, substituents independently selected from the group consisting of alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halo, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxyA group, a cycloalkylthio group, a heterocycloalkylthio group, an oxo group, and the like.

The term "ether group" means-O-R ₃ Wherein R is ₃ Substituents include, but are not limited to, substituents independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halogen, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, and the like.

The term "carboxy" refers to-R ₄ -COOH. Wherein R is ₄ Substituents include, but are not limited to, substituents independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halogen, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, and the like.

The term "amide group" refers to-C (O) -NH ₂ or-C (O) -NH-R ₅ or-C (O) -NR ₅ (R ₆ ) Wherein R is ₅ Substituents include, but are not limited to, substituents independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halogen, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, and the like; r is R ₆ Substituents include, but are not limited to, substituents independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halogen, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, and the like.

The term "sulfo" refers to-R ₇ -SO ₃ H. Wherein R is ₇ Substituents include, but are not limited to, substituents independently selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthio, alkylamino, halo, mercapto, hydroxy, nitro, cyano, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, cycloalkoxy, heterocycloalkoxy, cycloalkylthio, heterocycloalkylthio, oxo, and the like。

Calixarene is a macrocyclic compound composed of methylene bridged phenol units, has flexible and changeable structure and is easy to modify. The upper edge of the calixarene is a substituent connected with a benzene ring, and different substituents can be introduced by controlling different reaction conditions, so that the calixarene has various reaction activities. When alkyl, ester, ketone, ether, carboxyl, sulfo or amide groups are introduced, the calixarene can form a complex with the adhesive, and can react chemically with the curing agent or form a complex through steric hindrance, so that the cohesiveness of the adhesive is improved. The hydrophilic phenolic hydroxyl group is arranged at the lower edge of the calixarene structure, and after the coordination compound is formed with cations and cationic compounds, the swelling failure of the adhesive caused by water molecules can be reduced. Meanwhile, the calixarene disclosed by the invention has better high-temperature stability. Therefore, the calixarene can improve the high temperature resistance and the humidity resistance of the adhesive

In some embodiments of the present disclosure, the R group of the supramolecular compound is an alkyl group; alternatively, the R group of the supramolecular compound is a tert-butyl group.

The R group type at the upper edge of the calixarene of the supermolecular compound can influence the bonding strength of the calixarene, an adhesive and a curing agent, and the tertiary butyl group has higher steric hindrance, so that the adhesive has stable bonding effect.

In some embodiments of the present disclosure, n of the supramolecular compound is an integer greater than 3 and less than or equal to 6, alternatively n of the supramolecular compound is 4. An increase or decrease in the number of supramolecular groups results in a decrease in the adhesion of the adhesive in high temperature and high humidity environments. When n is 4, the adhesive shows better adhesive force under high-temperature and high-humidity environment.

In some embodiments of the present disclosure, the mass fraction of supramolecular compounds in the binder is 15% -25%; alternatively, 17% -23%; still alternatively, 20%.

In the technical scheme of the embodiment of the disclosure, the long-term stability of the binder in a high-temperature and high-humidity environment can be obviously reduced when the content of the supermolecular compound is too high or too low. When the mass fraction of the supermolecular compound is in a proper range, the adhesive has stronger initial adhesive force and long-term stability in a high-temperature and high-humidity environment.

The cationic additive is a compound capable of coordinating with the phenolic hydroxyl groups of calixarene. The cations in the cationic additive may be selected from metal cations, organic cations, and the like.

Adhesives include, but are not limited to, epoxies, polyurethanes, silicones, polyimides, polyacrylates, polymethacrylates, methylates, phenolic-epoxies, and the like.

Curing agents refer to a class of substances that enhance or control the curing reaction. Curing agents include, but are not limited to, isocyanates, isocyanate-terminated prepolymers formed from the reaction of isocyanates with polyols, aliphatic polyamines, aliphatic amine adducts, amidoamines, aminopolyamide resins, cycloaliphatic amines, aromatic amines, araliphatic amines, mannich bases, ketimines, dicyandiamide, peroxides, and the like.

Solvents include, but are not limited to, ethers, acetates, esters, ketones, aromatic hydrocarbons, amides or alcohols. More specifically, the process is carried out, examples thereof include ethanol, gamma-butyrolactone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol, monoethyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol monomethyl ether, tripropylene ether, tetrahydrofuran, dioxane, acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, 2-heptanone, 3-heptanone, diacetone alcohol, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl glycolate, methyl 2-hydroxy-3-methylbutyrate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, methyl formate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl formate, n-butyl acetate, ethyl butyrate, n-propyl butyrate, isobutyric acid, isopropyl butyrate, N-butyl butyrate, methyl pyruvate, ethyl pyruvate, N-propyl pyruvate, methyl acetoacetate, ethyl 2-oxobutyrate, aromatic compounds (e.g., toluene, xylene), amides (e.g., one or more of hydrocarbyl, N-methylpyrrolidone, N, N-dimethylformamide, and N, N-dimethylacetamide).

The cationic additive in the present disclosure can coordinate with the hydrophilic phenolic hydroxyl group at the lower edge of calixarene, reduce the hydrophilicity of the calixarene, make water molecules difficult to diffuse in the binder, and make the binder still have good binding effect in a humid environment. The adhesive is combined with the substituent group on the upper edge of calixarene through hydrogen bond, van der Waals force or electrostatic action, so that the bonding effect of the adhesive is enhanced. The curing agent can react with the upper edge substituent groups of the PET film and the calixarene and the adhesive, and can also form a complex with the upper edge substituent groups of the calixarene through steric hindrance, so that the PET film, the calixarene and the adhesive are better connected. The solvent can better fully and uniformly disperse each component, and each component is dissolved in the solvent, so that the coating performance of the adhesive is improved.

In some embodiments of the present disclosure, the cation of the cationic additive is selected from a metal cation or an organic cation, alternatively, the cation is Li ⁺ 、Na ⁺ 、K ⁺ 、NH ₄ ⁺ One or more of the following; still alternatively, the cation is Li ⁺ 。

In some embodiments of the present disclosure, the cationic additive is present in the binder in a mass fraction of 1% to 10%; alternatively, 1% -5%; still alternatively, 3%.

The cationic additive has the main function of coordinating with the hydroxyl at the lower edge of calixarene, reducing the hydrophilicity of the hydroxyl, and further improving the stability of the adhesive in a humid environment.

In some embodiments of the present disclosure, the adhesive is one or more of polyacrylic acid, polyurethane, epoxy, polyimide, optionally the adhesive is polyacrylic acid.

The term "polyacrylic acid" is a water-soluble high molecular polymer having the chemical formula (C ₃ H ₄ O ₂ ) _n N is a number greater than 0.

The term "polyurethane" is a high molecular polymer, which is known as polyurethane, and has the chemical formula (OCONH) _n N is a number greater than 0.

The term "epoxy resin" is a high molecular polymer, in particular a polymer of the type containing more than two epoxy groups, of the formula (C ₁₁ H ₁₂ O ₃ ) _n N is a number greater than 0.

The term "polyimide" is a class of polymers containing imide rings in the backbone, including but not limited to aliphatic polyimides, semiaromatic polyimides, aromatic polyimides, and the like.

In some embodiments of the present disclosure, the mass fraction of the adhesive in the binder is 30% -40%; alternatively, 32% -38%; still alternatively, 35%.

In some embodiments of the present disclosure, the curing agent includes one or more of a mono-isocyanate, a di-isocyanate, and a polyisocyanate, optionally the curing agent is a di-isocyanate.

The term "isocyanate" is a generic term for various esters of isocyanic acid. Isocyanates include, but are not limited to, monoisocyanates, diisocyanates, polyisocyanates, and the like.

The term "monoisocyanate" includes, but is not limited to, methyl isocyanate, n-butyl isocyanate, t-butyl isocyanate, phenyl isocyanate, p-chlorophenyl isocyanate, 3, 4-dichlorophenyl isocyanate, 3, 5-dichlorophenyl isocyanate, p-methylphenyl isocyanate, 3-chloro-4-methylphenyl isocyanate, p-isopropylphenyl isocyanate, p-bromophenyl isocyanate, p-nitrophenyl isocyanate, 4- (p-chlorophenoxy) -phenyl isocyanate, and the like.

The term "diisocyanate" includes, but is not limited to, toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, and the like.

The term "polyisocyanate" includes, but is not limited to, triphenylmethane triisocyanate, 4, -triisocyanato phenyl phosphate, 4, -triisocyanato phenyl thiophosphate, and the like.

In some embodiments of the present disclosure, the mass fraction of the curing agent in the binder is 1% -5%; alternatively, 2% -4%; still alternatively, 2%.

The isocyanate group in the isocyanate can react with the terminal hydroxyl group on the PET film, the upper edge substituent group of the supermolecular compound and the hydroxyl group of the adhesive, and can also form a complex with the upper edge substituent group of the supermolecular compound through steric hindrance, thereby playing a good role in connection. The curing agent with reasonable range can optimize the reaction proportion of each component, coordinate the functions of each component and lead the adhesive to achieve good bonding performance.

In some embodiments of the present disclosure, the mass fraction of solvent in the binder is 30% -50%; alternatively, 35% -45%; still alternatively, 40%.

In the technical scheme of the embodiment of the disclosure, the selected solvent can enable the supermolecular compound, the curing agent, the adhesive and the cationic additive to form a uniformly dispersed system, so that the coating performance of the adhesive is improved, and the adhesive and the surface of the matrix film are facilitated to react. Too high a solvent mass fraction can cause too thin of the binder, which is unfavorable for adhesion of the binder to the surface of the substrate film, and too low a solvent mass fraction can cause too thick of the binder and uneven distribution of components, which can reduce the coating performance of the binder.

According to one embodiment of the present disclosure, the present disclosure provides a use of an adhesive in the preparation of a tape.

Adhesive tape

According to one embodiment of the present disclosure, the present disclosure provides an adhesive tape comprising an adhesive and a substrate as disclosed herein.

In some embodiments of the present disclosure, the PET film has a hydroxyl number of 40-400mg/g, defined as: the quality of NaOH required for neutralizing the generated acetic acid is obtained after the unit mass of PET film is subjected to acetylation and hydrolysis.

By introducing hydroxyl functional groups on the surface of the matrix film, the reactivity of the film surface can be improved, and favorable conditions are created for the adhesion of the binder and the matrix film.

The degree of hydroxylation can influence the combination degree of the PET film and the binder, and too high hydroxylation degree can influence the hydrolysis degree of the PET film, so that the PET film is decomposed and failed and is excessively hydrophilic. The reasonable hydroxyl value range is set, so that a certain number of hydroxyl groups are left on the surface of the PET film, and meanwhile, the stability of the polymer film is not affected. The hydroxyl value is calculated as follows:

wherein:

i (OH) is the hydroxyl number in mg/g;

v1 is the volume of NaOH solution consumed in blank test, and the unit is mL;

V2 is the volume of NaOH solution consumed by the sample, per mL;

c is the concentration of NaOH solution, and the unit mol/L;

40 is the molar mass of NaOH;

m is the mass of the sample, and is the unit g;

x is the pH value of the sample, and is measured according to the method specified in GB/T6365, if the value is smaller than 0.3 and can be ignored, the arithmetic average value of the two measurement results is taken.

Preparation method of adhesive tape

According to an embodiment of the present disclosure, the present disclosure further provides a method for preparing an adhesive tape, the method comprising the steps of:

the organic supermolecular compound, the cationic additive, the adhesive, the curing agent and the solvent are mixed, and the resulting adhesive is coated on at least part of the surface of the PET film.

In some embodiments of the present disclosure, the PET film is subjected to a hydroxylation treatment with a hydroxylation reagent of 98% H by mass ₂ SO ₄ Aqueous solution, piranha solution, 10 mass% FeSO ₄ 30% by mass of H ₂ O ₂ One or more of the aqueous solutions, optionally a piranha solution; the adhesive is applied at a thickness of 50-100 μm, alternatively 50 μm.

In some embodiments of the present disclosure, a method of preparing an adhesive tape further comprises the steps of:

(1) Pretreatment: soaking a PET film in a cleaning agent for 10-20min at normal temperature (25 ℃ and the same below) by using one of alcohol, ethyl acetate or methyl formate as the cleaning agent, flushing with deionized water for 3 times after the soaking is finished, and naturally airing at normal temperature to obtain a sample A;

(2) Hydroxylation treatment: mixing the prepared piranha solution (concentrated H ₂ SO ₄ And 30 mass% of H ₂ O ₂ Uniformly coating the solution on one side surface of a sample A in a volume ratio of 3:1-7:1, reacting for 10-20min at normal temperature, washing the surface of the sample A by deionized water until the surface is nearly neutral (measured by pH test paper, the pH range is 6.5-7.0), and performing reaction under normal temperature conditionsNaturally airing to obtain a sample B;

(3) Coating of the adhesive: mixing 30-40% of adhesive, 15-20% of calixarene, 30-50% of solvent, 1-5% of curing agent and 1-5% of cationic additive, uniformly coating on the surface of sample B subjected to hydroxylation treatment, and coating the surface with the thickness of 50-100 mu m to obtain the adhesive tape.

In the technical scheme of the embodiment of the disclosure, the PET film has an ester functional group, and if an alkaline reagent is used for carrying out the reduction reaction of the ester, the PET substrate is easy to break. Hydroxyl is introduced under the acidic condition, and the hydroxyl is generated by utilizing the radical substitution reaction, namely, the ester bond reaction of oxygen radicals and the PET film, so that the damage to the ester bond in the PET film can be avoided. The reasonable coating thickness can improve the binding force between the PET film and the binder, and is also beneficial to the high temperature resistance and the moisture resistance of the adhesive tape.

According to one embodiment of the present disclosure, the present disclosure also provides an electrochemical device comprising the adhesive tape as disclosed herein.

The technical aspects of the present disclosure will be more clearly and clearly illustrated below by way of example in conjunction with examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure in any way. The scope of the present disclosure is limited only by the claims.

Examples

Unless otherwise indicated, the reagents and equipment used in the examples below are all conventional products commercially available. Unless otherwise indicated, experiments were performed under conventional conditions or conditions suggested by the manufacturer.

Example 1

(1) Pretreatment: using alcohol as a cleaning agent, soaking a PET film in alcohol for 15 minutes at normal temperature (25 ℃ and the same below), flushing with deionized water for 3 times after soaking, and naturally airing at normal temperature to obtain a sample A;

(2) Hydroxylation treatment: the piranha solution (concentrated H) ₂ SO ₄ And 30 mass% of H ₂ O ₂ The volume ratio of the solution is 5:1) is evenly coated on one side surface of the sample A, after reaction for 15 minutes at normal temperature, deionized water is used for flushing until the surface of the sample A is nearly neutral (measured by using pH test paper, the pH range is 6.5-7.0), and the sample B is obtained by natural airing at normal temperature;

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Example 2

(2) Hydroxylation treatment: the piranha solution (concentrated H) ₂ SO ₄ And 30 mass% of H ₂ O ₂ The volume ratio of the solution is 3:1) is evenly coated on one side surface of the sample A, after reaction for 15 minutes at normal temperature, deionized water is used for flushing until the surface of the sample A is nearly neutral (measured by using pH test paper, the pH range is 6.5-7.0), and the sample B is obtained by natural airing at normal temperature;

Example 3

(2) Hydroxylation treatment: the piranha solution (concentrated H) ₂ SO ₄ And 30 mass% of H ₂ O ₂ The volume ratio of the solution is 7:1) is evenly coated on one side surface of the sample A, after reaction for 15 minutes at normal temperature, deionized water is used for flushing until the surface of the sample A is nearly neutral (measured by using pH test paper, the pH range is 6.5-7.0), and the sample B is obtained by natural airing at normal temperature;

(3) Coating of the adhesive: the surface of sample B subjected to hydroxylation treatment is uniformly coated with the adhesive tape with the thickness of 50 mu m, wherein the mass fraction of the adhesive tape is 35 percent of polyacrylic acid, the mass fraction of the para-tertiary butyl calix [4] arene is 20 percent, the mass fraction of LiCl is 3 percent, the mass fraction of toluene is 40 percent, and the mass fraction of diisocyanate is 2 percent.

Example 4

(3) Coating of the adhesive: the adhesive tape is prepared by mixing 38% by mass of polyacrylic acid, 17% by mass of p-tert-butylcalix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m.

Example 5

(3) Coating of the adhesive: the method comprises the steps of mixing 32% by mass of polyacrylic acid, 23% by mass of p-tert-butylcalix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Example 6

(3) Coating of the adhesive: the method comprises the steps of mixing 32% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 6% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Example 7

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 3% by mass of NaCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Example 8

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 40 mu m to obtain the adhesive tape.

Example 9

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 60 mu m to obtain the adhesive tape.

Example 10

(3) And (3) coating a binder. The specific method comprises the following steps: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-sulfonic calix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Example 11

(2) Hydroxylation treatment: the piranha solution (concentrated H) ₂ SO ₄ And 30 percent ofMass) H ₂ O ₂ The volume ratio of the solution is 5:1) is evenly coated on one side surface of the sample A, after reaction for 15 minutes at normal temperature, deionized water is used for flushing until the surface of the sample A is nearly neutral (measured by using pH test paper, the pH range is 6.5-7.0), and the sample B is obtained by natural airing at normal temperature;

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [6] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Example 12

(1) Pretreatment: using alcohol as a cleaning agent, soaking a PET film in alcohol for 15 minutes at normal temperature (25 ℃ and the same below), flushing the soaking position with deionized water for 3 times, and naturally airing at normal temperature to obtain a sample A;

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [8] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Comparative example 1

(3) Coating of the adhesive: the methacrylate structural adhesive with the trade name ERGO 1665 is uniformly coated on the surface of the sample B subjected to hydroxylation treatment, and the coating thickness is 50 mu m, so that the adhesive tape is obtained.

Comparative example 2

(2) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on one side surface of a sample A, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Comparative example 3

(3) Coating of the adhesive: the adhesive tape is prepared by mixing 38% by mass of polyacrylic acid, 20% by mass of p-tert-butylcalix [4] arene, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m.

Comparative example 4

(3) Coating of the adhesive: the adhesive tape is prepared by mixing 35% by mass of polyacrylic acid, 23% by mass of p-tert-butylcalix [4] arene, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m.

Comparative example 5

(1) Pretreatment: soaking a PET film in alcohol for 15 minutes under the condition of normal temperature (25 ℃ and the same below) by using one of the alcohol as a cleaning agent, flushing with deionized water for 3 times after the soaking is finished, and naturally airing at normal temperature to obtain a sample A;

(3) Coating of the adhesive: the method comprises the steps of mixing 35% by mass of polyacrylic acid, 20% by mass of calix [4] arene without upper edge substituent, 3% by mass of LiCl, 40% by mass of toluene and 2% by mass of diisocyanate, uniformly coating the mixture on the surface of a sample B subjected to hydroxylation treatment, and coating the mixture to a thickness of 50 mu m to obtain the adhesive tape.

Comparative example 6

(3) Coating of sample B with 0.5g of diisocyanate on the hydroxylated surface

To further illustrate the variation in content between samples, the sample parameters of the above examples and comparative examples are summarized in table 1 below:

table 1 summary of example and comparative parameters table

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Test method

Fourier infrared spectrum testing (FTIR), long term adhesion at different temperatures (25 ℃, 60 ℃) and long term adhesion at different humidity (50%, 90%, 100%) were performed for the above examples and comparative examples.

1. Fourier infrared spectroscopy experiments

Experimental method

Solid film sample: fixing the film or the film coated with the adhesive between two KBr salt sheets for measurement;

solid powder sample: crushing 0.5 mg-1.0 mg of powder sample and about 150mg of KBr, pressing into transparent slices by a tablet press, and measuring;

liquid sample: two KBr salt plates were used, 1-2 drops of liquid were placed on the salt plates, and the salt plates were sandwiched between the other plates, and after fixing, the measurement was performed with care being taken not to allow air bubbles to mix in.

Experimental sample

(1) Characterization of PET film before and after hydroxylation: the samples from which step 1-2 of example 1 were completed were compared with the PET film that was not hydroxylated and the FTIR data were tested.

(2) Reaction characterization of hydroxylated PET film with diisocyanate: the sample obtained from step 1-2 of example 1 was compared with the sample obtained from comparative example 6 and the test FTIR data was compared.

(3) Reaction characterization of calixarene with polyacrylic acid and diisocyanate: the test FTIR data were taken for comparison of example 1, example 5 and example 10.

(4) Calixarene reaction characterization with cationic additives: the test FTIR data were taken for comparison of example 1 with comparative example 3.

Experimental results and discussion

(1) Characterization of PET film before and after hydroxylation

After hydroxylation of the surface of the PET film, more hydroxyl (-OH) groups are introduced into the PET molecular chain, and hydrogen bonds are very easy to form among the hydroxyl groups. However, since the PET film is a solid film, there is a large steric hindrance between the hydroxyl groups (-OH) on the surface of the PET film, and as can be seen from FIG. 1, the hydroxyl groups are 3200-3300cm ^-1 The position shows a sharp stretching vibration peak; at 2890cm ^-1 A stronger absorption peak appears at the position, which corresponds to the aromatic C-H stretching vibration peak in PET.

(2) Hydroxylated PET film and diisocyanate reaction characterization

As can be seen from FIG. 2, 3200 to 3300cm was found after the reaction of the hydroxylated PET film with diisocyanate ^-1 The hydroxyl vibration peak at the position is obviously enhanced and the width is increased, which indicates that the diisocyanate and PET have the bonding effect of hydrogen bonds; is influenced by diisocyanate of 2890cm ^-1 The aromatic C-H vibration peak at the position shifts to high wave number and differentiation occurs, 1750 cm to 1850cm ^-1 The reaction is carried out on the antisymmetric stretching vibration peak corresponding to the diisocyanate N=C=O, and the vibration peak at the antisymmetric stretching vibration peak is obviously enhanced.

(3) Reaction characterization of calixarene and polyacrylic acid and diisocyanate

As can be seen from FIG. 3, the results of comparative examples 1 and 5 show that 3200-3300cm after increasing the calixarene ratio and decreasing the polyacrylic acid ratio ^-1 The hydroxyl vibration peak at the position is obviously weakened, and the hydrogen bond formed by polyacrylic acid and calixarene is reduced after the proportion is changed; comparative example 1 and example 10, after the substitution of the calixarene upper edge group with a sulfonic acid group, the shift of the hydroxyl vibration peak to low wavenumber occurs and the intensity is reduced, since the sulfonic acid group tends to form intramolecular hydrogen bonds; at 900cm ^-1 The absorption peak appearing at this point corresponds to the S-O stretching vibration in the sulfonic acid group.

(4) Calixarene and cationic additive reaction characterization

As is clear from FIG. 4, the results of comparative examples 1 and 3 show that the cationic additive was added at 2280cm ^-1 Calixarene and Li appear at the site ⁺ Symmetrical stretching vibration peak of coordination between 700 cm and 1600cm ^-1 A series of absorption peaks associated with the diisocyanate-NCO appear, indicating that the cationic additive significantly enhances the calixarene-diisocyanate combination.

2. Adhesion test at 25℃and 60 ℃

Experimental method

(1) The sample tapes of examples 1-12 and comparative examples 1-5 were prepared as standard samples 150mm long and 20mm wide, and simultaneously prepared as an aluminum sheet (1 mm thick) of the same size;

(2) The surfaces of the standard samples were bonded to aluminum sheets 150mm long and 20mm wide in full overlap and stored at 25℃and 60℃for 2 hours, 24 hours and 48 hours, respectively. After the storage time was reached, the aluminum sheet bonded with the standard sample and the standard sample were torn 10mm in the longitudinal direction, and the aluminum sheet and the standard sample separated by 10mm were clamped into a CMT6104 type universal testing machine (manufacturer: metts (MTS)) to conduct a tensile test (tensile speed: 20mm/min, tensile direction perpendicular to the ground), and the maximum value of the tensile curve was taken as the bonding force of the standard sample (modified tape).

Experimental results and discussion

The test results are shown in Table 2.

Table 2 data for different temperature adhesion test

According to the test results in Table 2 above, the adhesion of examples 1 to 12 was better than that of comparative example 1 after storage at 25℃and 60℃for 2, 24 and 48 hours (50% humidity), with the adhesion of example 1 being the best. From example 1 and comparative examples 2 to 5, it is understood that if the PET film is not subjected to hydroxylation treatment, the binder is not added with a cationic additive or the R group of calixarene is not substituted, the adhesive strength of the adhesive tape is reduced under a high temperature environment. As can be seen from examples 1 and 4 to 5, if the mass fraction of the polyacrylic acid is increased, the mass fraction of the calixarene is reduced in the adhesive, which is favorable for improving the initial adhesive force of the adhesive tape, but the long-term high-temperature stability is reduced; conversely, if the mass fraction of polyacrylic acid is reduced and the mass fraction of calixarene is increased, the initial adhesion of the tape is reduced. From examples 1 and 6, it is seen that increasing the proportion of cationic additive reduces the long-term stability of the tape in high temperature environments. From examples 1 and 7, it is understood that the initial adhesion and long-term stability of the adhesive tape at high temperature are reduced by replacing the cationic additive. From examples 1 and 8 to 9, it is understood that the increase in the adhesive coating thickness reduces the long-term temperature property of the adhesive tape under a high-temperature environment. From examples 1, 11-12, it is seen that as the number of supermolecular groups of calixarene increases, the adhesive power and long-term stability of the adhesive tape decrease with increasing temperature. In summary, it is clear that the tape of example 1 has an optimal degree of surface hydroxylation of the PET film, polyacrylic acid and calixarene content, and cationic additive content, and the calixarene upper edge substituent group type and the phenol unit number are good.

3. Adhesion test at 90-100% humidity

Experimental method

(1) The sample tape in the above example was prepared into a standard sample 150mm long and 20mm wide, and an aluminum sheet (thickness 1 mm) of the same size was prepared at the same time;

(2) The surfaces of the standard samples were bonded to aluminum sheets 150mm long and 20mm wide in a completely overlapping manner, and stored at 50%, 90% and 100% humidity for 2 hours, 24 hours and 48 hours, respectively. After the storage time was reached, the aluminum sheet bonded with the standard sample and the standard sample were torn 10mm in the longitudinal direction, and the aluminum sheet and the standard sample separated by 10mm were clamped into a CMT6104 type universal testing machine (manufacturer: metts (MTS)) to conduct a tensile test (tensile speed: 20mm/min, tensile direction perpendicular to the ground), and the maximum value of the tensile curve was taken as the bonding force of the standard sample (modified tape).

Experimental results and discussion

The test results are shown in table 3:

table 3 different humidity adhesion test data

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According to the test results in Table 3 above, the adhesion of examples 1-12 was better than that of comparative example 1 after storage at 50%, 90% and 100% humidity (25 ℃) for 2, 24 and 48 hours, with example 1 being the most adhesive. From example 1 and comparative examples 2 to 5, it is understood that if the PET film is not subjected to hydroxylation treatment and the R group to which the cationic additive or calixarene is not added in the adhesive is not substituted, the adhesive strength of the adhesive tape in a high humidity environment is reduced. From examples 1 to 3, it is understood that the increase in the degree of hydroxylation of the surface of the PET film results in a decrease in the long-term stability of the adhesive tape under a high humidity environment. As can be seen from examples 1 and 4 to 5, if the mass fraction of the polyacrylic acid is increased, the mass fraction of the calixarene is reduced in the adhesive, which is favorable for improving the initial adhesive force of the adhesive tape, but the long-term high-humidity stability is reduced; conversely, if the mass fraction of polyacrylic acid is reduced and the mass fraction of calixarene is increased, the initial adhesion of the tape is reduced. From examples 1 and 6, it is understood that increasing the proportion of cationic additive reduces both the initial adhesion and the long-term stability of the tape in a high-humidity environment. From examples 1 and 7, it is evident that the replacement of the cationic additive reduces the initial adhesion of the tape in a high humidity environment. As is evident from examples 1, 8-9, an increase in the adhesive coating thickness resulted in a certain increase in the adhesive strength of the tape, but reduced the long-term stability of the tape in a high humidity environment. From examples 1, 11-12, it is seen that as the number of supermolecular groups of calixarene increases, the adhesive power and long-term stability of the adhesive tape decrease with increasing humidity. In summary, the adhesive tape of example 1 has the optimal degree of hydroxylation on the surface of the PET film, the content of polyacrylic acid and calixarene and the content of cationic additive under the high humidity environment, and the upper edge substituent species of the calixarene and the number of phenol units are better.

Claims

1. A binder comprising a supermolecular compound which is a calixarene having a structure represented by the following formula (1) and an adhesive,

n is selected from integers greater than 3;

the mass fraction of the supermolecule compound in the binder is 15% -25%, and the mass fraction of the adhesive in the binder is 30% -40%.

2. The binder of claim 1, wherein the R group in the supramolecular compound is an alkyl group.

3. The binder of any of claims 1-2, wherein the R group in the supramolecular compound is a tert-butyl group.

4. The binder of any one of claims 1-3, wherein n in the supramolecular compound is an integer greater than 3 and less than or equal to 6.

5. The binder of any one of claims 1-4, wherein n in the supramolecular compound is 4.

6. The binder of any of claims 1-5, wherein the supramolecular compound is present in the binder in a mass fraction of 17% -23%.

7. The binder of claim 6, wherein the supramolecular compound is present in the binder in an amount of 20% by mass.

8. The binder of any of claims 1-7, wherein the binder further comprises one or more of a cationic additive, a curing agent, a solvent.

9. The binder of claim 8, wherein the cation of the cationic additive is a metal cation or an organic cation.

10. The binder of claim 8, wherein the cation is Li ⁺ 、Na ⁺ 、K ⁺ 、NH ₄ ⁺ One or more of the following.

11. The binder of claim 8, wherein the cation is Li ⁺ 。

12. The adhesive of claim 1, wherein the adhesive is one or more of polyacrylic acid, polyurethane, epoxy, polyimide.

13. The adhesive of claim 1 wherein the adhesive is polyacrylic acid.

14. The adhesive of claim 8, wherein the curing agent is one or more of a mono-isocyanate, a di-isocyanate, and a polyisocyanate.

15. The adhesive of claim 8 wherein the curing agent is a diisocyanate.

16. The binder of claim 8, wherein the solvent comprises one or more of carbon tetrachloride, ethyl acetate, methyl formate, ethanol, toluene.

17. The adhesive of claim 8 wherein the solvent is toluene.

18. Use of the adhesive according to any one of claims 1 to 17 for the preparation of adhesive tape.

19. A tape comprising the adhesive of any one of claims 1-17 and a substrate.

20. The tape of claim 19, wherein the substrate is a hydroxylated polyethylene terephthalate film.

21. A method of making the tape of claim 19, the method comprising the steps of:

mixing a supermolecular compound, a cationic additive, an adhesive, a curing agent and a solvent to obtain a binder, and coating the obtained binder on at least part of the surface of the polyethylene terephthalate film.

22. The production method according to claim 21, wherein the polyethylene terephthalate film is subjected to hydroxylation treatment, and a hydroxylating agent98% by mass of H ₂ SO ₄ Aqueous solution, piranha solution, 10% by mass FeSO ₄ -30% by mass H ₂ O ₂ One or more of the solutions; the coating thickness of the adhesive is 50-100 mu m.

23. The method of manufacture of claim 22, wherein the hydroxylating agent is a piranha solution; the adhesive was applied to a thickness of 50 μm.

24. An electrochemical device comprising the tape of claim 19.