Two-component (2K) curable adhesive composition

Abstract

The present invention relates to a curable and peelable two-component adhesive composition, wherein i) the first component contains a (meth)acrylate monomer, a copolymerizable acid, and an electrolyte, and ii) the second component contains a first curing agent for the monomer of the first component, a second curing agent for the monomer of the first component, a wax, and a solubilizing agent, and the two-component (2K) adhesive composition further contains a reinforcing agent, an oxygen scavenger, and a rheology control agent. Further, in the two-component adhesive composition, the electrolyte contains at least one salt described in Formula (I) or Formula (II), or consists of the salt. JPEG2025520529000024.jpg41141

Description

Technical Field

[0001] Technical Field of the Invention The present invention relates to an adhesive composition that can be peeled from a specifically coated substrate. More specifically, the present invention relates to a curable and peelable two-component (2K) adhesive composition that is particularly useful for bonding electronic components.

Background Art

[0002] Background of the Invention Adhesive bonding and polymer coating are generally used in the assembly and finishing of manufactured products. They are used in place of mechanical fasteners such as screws, bolts, and rivets, reducing machining costs and providing adhesion with higher adaptability in the manufacturing process. Adhesive bonding evenly distributes stress, reduces the possibility of fatigue, and blocks the joint from corrosion species.

[0003] Thus, adhesive bonding offers many advantages over mechanical fasteners, but when required in actual applications, it tends to be difficult to disassemble the adhesively bonded articles. Removal of the adhesive by mechanical processes such as sandblasting or wire brushing is generally excluded because, for one, the adhesive is placed between the substrates and thus cannot be accessed without damaging the surface of the substrate or is difficult to polish. Degradation by the application of chemicals and / or high temperatures as disclosed in U.S. Patent No. 4,171,240 (Wong), U.S. Patent No. 4,729,797 (Linde et al.), and US 20140287299 A1 (Krogdahl) may be effective but can be time-consuming and complex to implement. Further, the required aggressive chemicals or harsh conditions can damage the separated substrates and render them unsuitable for subsequent applications.

[0004] As an example, it is clear that components of electronic devices such as personal computers, laptops, and tablets are attached within the device using adhesives and thus it is desirable to remove, replace, and / or recycle them. However, such adhesives are typically strong in that they are designed to maintain adhesion both during drops and impacts and over a wide range of operating temperatures and other environmental conditions. Thus, without care, device components bonded with adhesives can be damaged or destroyed when removing the components by mechanical processes, application of chemicals, or high temperatures.

[0005] In view of these problems, certain authors have attempted to develop a detachable adhesive composition in which a cured composition acts to break the adhesion at the interface between the adhesive and the substrate by the flow of an electric current.

[0006] U.S. Patent No. 7,465,492 (Gilbert) describes a detachable composition that includes a matrix functionality, a free radical initiator, and an electrolyte that includes a monomer selected from the group consisting of acrylic, methacrylic, and combinations thereof, wherein the electrolyte provides the composition with sufficient ionic conductivity to support a Faraday reaction in the adhesion formed between the composition and a conductive surface, whereby the composition can be detached from the surface.

[0007] U.S. Patent Application Publication No. 2007 / 0269659 (Gilbert) describes a detachable adhesive composition at two interfaces, wherein the composition (i) includes a polymer and an electrolyte, (ii) facilitates the bonding of two surfaces, and (iii) detaches from both the anode and cathode surfaces in response to a voltage applied across both surfaces to form an anode interface and a cathode interface.

[0008] U.S. Patent Application Publication No. 2008 / 0196828 (Gilbert) describes a hot melt adhesive composition comprising a thermoplastic component and an electrolyte, wherein the electrolyte provides sufficient ionic conductivity to the composition to enable a Faraday reaction in the bond formed between the composition and a conductive surface, thereby enabling the composition to be peeled from the surface.

[0009] International Application Publication No. 2017 / 133864 (Henkel AG & Co. KGaA) describes a method for reversibly bonding a first and a second substrate, wherein at least the first substrate is a non-conductive substrate, and the method comprises: a) coating the surface of the non-conductive substrate with a conductive ink; b) applying an electrically peelable hot melt adhesive composition to the surface of the first substrate and / or the second substrate coated with the conductive ink; c) bringing the first substrate into contact with the second substrate such that the electrically peelable hot melt adhesive composition is interposed between the two substrates; d) forming an adhesive bond between the two substrates to provide an adhered substrate; e) applying a voltage to the adhered substrate, thereby substantially weakening the adhesion at at least one interface between the electrically peelable hot melt adhesive composition and the substrate surface.

[0010] European Patent Publication No. 3835381 (Henkel AG & Co. KGaA) describes a curable and peelable two-component (2K) adhesive composition comprising: i) a first component comprising a (meth)acrylate monomer, a copolymerizable acid and an electrolyte; and ii) a second component comprising a first curing agent for the monomer of the first component, a second curing agent for the monomer of the first component and a solubilizer.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

[0012] There is still a technical need to provide an adhesive composition that can be easily applied to the surface of a substrate to be adhered and can provide an effective bond within a composite structure including the substrate upon curing, but can be effectively peeled from those substrates by simply applying a potential to the entire cured adhesive. In particular, the inventors have recognized the need in the art to develop a peelable adhesive that can be applied to the surface of a substrate to be joined without deterioration of the joints within the composite structure even when the substrate is exposed to high humidity and high temperature conditions. Such a peelable adhesive would be advantageously utilized especially in electronic devices. [Means for Solving the Problems]

[0013] Description of the Invention According to a first aspect of the present invention, (meth)acrylate monomer, copolymerizable acid, and electrolyte a first component (A) containing a first curing agent for the monomer of the first component, a second curing agent for the monomer of the first component, wax, and solubilizer, A second component (B) containing A curable and peelable two-component (2K) adhesive composition is provided, wherein the two-component adhesive composition further comprises A reinforcing agent; An oxygen scavenger; and A rheology control agent; and comprises Furthermore, the two-component adhesive composition has the electrolyte being of formula (I) or formula (II): JPEG2025520529000002.jpg40139[wherein R 1 , R 2 , R 3 , R 4 and R 5 are independently selected from hydrogen, C1-C 18 alkyl, C3-C 18 cycloalkyl, C6-C 18 aryl, C7-C 24 aralkyl, C2-C 20 alkenyl, -C(O)R q , -C(O)OH, -CN or -NO2, and R q is C1-C6 alkyl, and X- is JPEG2025520529000003.jpg26133is a counter anion selected from the group consisting of (wherein R a and R b are independently selected from hydrogen, C1-C 12 alkyl, C5-C 12 cycloalkyl, C5-C 12 heterocycloalkyl, C6-C 18 aryl or C5-C 18 heteroaryl)] Characterized by containing or consisting of at least one salt as described in

[0014] The reinforcing agent, oxygen scavenger and rheology control agent may be included in one or both parts of the composition. However, it is preferable that the first component of the composition containing the reactive monomer also contains the reinforcing agent, oxygen scavenger and rheology control agent.

[0015] In an important aspect of the present invention, the two-component adhesive composition is as follows: Based on the weight of the first component: 20 to 80% by weight, preferably 30 to 60% by weight of (meth)acrylate monomer; 0.5 to 20% by weight, preferably 5 to 15% by weight of copolymerizable acid; and, 0.5 to 20% by weight, preferably 5 to 15% by weight of electrolyte; A first component (A) containing: Based on the weight of the second component: 5 to 40% by weight, preferably 10 to 40% by weight of a first curing agent; 0.01 to 2% by weight, preferably 0.01 to 1% by weight of a second curing agent; 5 to 30% by weight of wax, preferably 5 to 20% by weight; and 20 to 60% by weight of solubilizer, preferably 30 to 60% by weight, A second component (B) containing: including: Here, based on the total weight of the composition, the composition further contains 5 to 40% by weight, preferably 10 to 40% by weight of a reinforcing agent; 0.1 to 5% by weight, preferably 0.1 to 2% by weight of an oxygen scavenger; and 1 to 20% by weight of a rheology control agent.

[0016] The first component (A) and the second component (B) are usually blended at a weight ratio of A:B of 20:1 to 1:1, for example 15:1 to 5:1 or 12:1 to 8:1. A particularly preferred embodiment of the composition is a weight ratio of component A:component B of 10:1.

[0017] The composition according to these definitions has been demonstrated to provide excellent adhesion stability under high temperature and high humidity conditions. In the following examples, in particular, the stability at a relative humidity (RH) of 95% and 65 °C has been demonstrated. Furthermore, when a composite structure is formed using the cured adhesive composition, these structures can be easily peeled by applying a potential difference to the adhesive joint.

[0018] In the first component of the adhesive composition, the copolymerizable acid is preferably selected from the group consisting of methacrylic acid, acrylic acid, itaconic acid, maleic acid, aconitic acid, crotonic acid, fumaric acid, and mixtures thereof, and it is particularly noted that methacrylic acid is selected.

[0019] Separate from or in addition to this mention regarding the selection of the copolymerizable acid of the first component, the electrolyte is preferably 1-methylimidazolium bis(trifluoromethylsulfonyl)imide; 3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-propyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide; 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide; 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; tetraethylphosphonium bis(trifluoromethylsulfonyl)imide; tetrabutylphosphonium bis(trifluoromethylsulfonyl)imide; tridecyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; and mixtures thereof. In particular, it can be said that at least one of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide and 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide is preferred.

[0020] In the second component of the adhesive composition, the first curing agent is preferably a peroxide curing agent selected from the group consisting of tert-butyl peroxide, tert-butyl perbenzoate, cumene hydroperoxide, tert-butyl peroxybenzoate, diacetyl peroxide, benzoyl peroxide, tert-butyl peracetate, lauryl peroxide, and mixtures thereof, and the use of benzoyl peroxide is particularly preferred.

[0021] Separate from or in addition to this reference to the selection of the first curing agent, the second curing agent preferably consists of at least one compound which is any of a salt or complex of a transition metal selected from the group consisting of Fe, Co, V, Mn, and Cu. More preferably, the second curing agent comprises or consists of at least one iron-based compound selected from the group consisting of ferrocene, iron(II) acetylacetonate, and ammonium iron(3+) hexakis(cyano-C)ferrate(4-).

[0022] Separate from or in addition to this reference to the selection of the first and second curing agents, the solubilizer of the second component of the adhesive composition is a polyalkylene glycol or is preferably an epoxy resin selected from the group consisting of alicyclic epoxides, epoxy novolac resins, bisphenol-A-epoxy resins, bisphenol-F-epoxy resins, bisphenol-A epichlorohydrin-based epoxy resins, alkyl epoxides, limonene dioxide, polyepoxides, and mixtures thereof. Particular mention is made of the selection of a solubilizer comprising or consisting of bisphenol-A-epoxy resin.

[0023] According to a second aspect of the present invention, a first material layer having a conductive surface, and a second material layer having a conductive surface An adhesive structure is provided, wherein the curable and peelable two-component (2K) adhesive composition defined in the above and the appended claims is disposed between the first material layer and the second material layer.

[0024] According to a third aspect of the present invention, i) a step of applying a voltage to the entire surface of both sides to form an anode interface and a cathode interface, and ii) a step of peeling the above two surfaces is included A method for peeling the above-described and attached adhesive structure defined in the appended claims is provided.

[0025] Step i) of this method preferably a) an applied voltage of 0.5 to 100 V, and b) a voltage applied for 1 second to 60 minutes is characterized by at least one of them.

Brief Description of the Drawings

[0026]

Fig. 1a

Fig. 1b

Fig. 2a

Fig. 2b

Mode for Carrying Out the Invention

[0027] Definition As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

[0028] As used herein, the terms "comprising" and "comprised of" are synonymous with "including", "includes", "containing" or "contains", are inclusive or open-ended, and do not exclude additional, unrecited members, elements, or method steps.

[0029] As used herein, the term "consisting of" excludes unspecified elements, components, members, or method steps.

[0030] When a quantity, concentration, dimension, or other parameter is expressed in the form of a range, a preferred range, an upper limit, a lower limit, or a preferred upper limit and a limit value, any range obtained by combining any upper or preferred value with any lower or preferred value should be understood to be specifically disclosed, regardless of whether the resulting range is explicitly recited in the context.

[0031] Furthermore, according to standard understanding, a weight range expressed as "0 to x" specifically includes 0 weight %. The component defined by this range may not be present in the composition or may be present in the composition in an amount up to a maximum of x weight %.

[0032] The words "preferred", "preferably", "desirably" and "particularly" are frequently used herein to draw attention to embodiments of the present disclosure that may provide certain benefits under certain circumstances. However, the description of one or more preferred, preferable, desirable, or particular embodiments is not intended to imply that other embodiments are not useful, nor is it intended to exclude those other embodiments from the scope of the present disclosure.

[0033] As used in this application, the word "may" is used in a permissive sense, not an obligatory sense. That is, it means there is a possibility.

[0034] As used herein, room temperature is 23 °C plus or minus 2 °C. As used herein, "ambient conditions" means the temperature and pressure surrounding the composition or the substrate of the coating layer or the coating layer where the composition or the substrate is disposed.

[0035] In the context of the present invention, a "two-component (2K) composition" is understood to be a composition in which the first component (A) and the second component (B) must be stored in separate containers due to their (high) reactivity. The two components are mixed only immediately before application and then react to form an adhesive bond and thereby a polymer network, usually without additional activation. Herein, a higher temperature can be applied to accelerate the cross-linking reaction.

[0036] As used herein, the term "removable" means that after curing of the adhesive, when a potential of 5 V to 75 V is applied for 1 second to 60 minutes, the adhesive strength can be reduced by at least 50%. The cured adhesive is applied between two substrates adhered by the adhesive such that an electric current flows through the adhesive bond line. The adhesive strength is measured by a tensile lap shear (TLS) test based on the determination of the tensile lap shear strength of adhesive assemblies according to EN 1465:2009 (German version) adhesives, performed at room temperature.

[0037] As used herein, the term "monomer" refers to a substance that can undergo a polymerization reaction and contribute to the structural units of the polymer's chemical structure. The term "monofunctional" as used herein refers to the possession of one polymerizable moiety. The term "polyfunctional" as used herein refers to the possession of multiple polymerizable moieties.

[0038] As used herein, the term "equivalent (eq.)" relates to the relative number of reactive groups present in a reaction, as is common in chemical notation.

[0039] As used herein, the term "electrolyte" is used to refer to a substance that contains free ions capable of conducting electricity by the movement of charged carrier species, in accordance with its standard meaning in the art. This term is intended to encompass molten electrolytes, liquid electrolytes, semi-solid electrolytes, and solid electrolytes, at least one of the cationic or anionic components of their electrolyte structures being essentially free to move and thus acting as charge carriers.

[0040] The curable adhesive composition and the cured adhesive obtained therefrom of the present invention have "electrolyte functionality" in that the adhesive material enables the conduction of either or both of ions, anions, or cations. The electrolyte functionality is understood to be derived from the ability of the composition and the cured adhesive to solvate at least one polar ion.

[0041] As used herein, "(meth)acrylic" is a shortened form referring to "acrylic" and / or "methacrylic". Thus, the term "(meth)acrylamide" refers to acrylamide and methacrylamide collectively.

[0042] As used herein, "C1-C n alkyl" group refers to a monovalent group containing from 1 to n carbon atoms. This is a group of an alkane and includes linear and branched organic groups. Thus, "C1-C 18 alkyl" group refers to a monovalent group containing from 1 to 18 carbon atoms, which is a group of an alkane and includes linear and branched organic groups. Generally, an alkyl group containing from 1 to 12 carbon atoms (C1-C 12An alkyl group, for example an alkyl group containing from 1 to 8 carbon atoms (C1-C8 alkyl), is noted as being preferred. Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, and 2-ethylhexyl. In the present invention, such an alkyl group may be unsubstituted or substituted with one or more halogens. Where applicable to a given moiety (R), the allowable range of one or more non-halogen substituents within the alkyl group is described herein.

[0043] As used herein, the term "C1-C 18 hydroxyalkyl" refers to an HO-(alkyl) group having from 1 to 18 carbon atoms, with the point of attachment of the substituent being via an oxygen atom and the alkyl group being as defined above.

[0044] An "alkoxy group" refers to a monovalent group represented by -OA, where A is an alkyl group, and non-limiting examples thereof are a methoxy group, an ethoxy group, and an isopropyloxy group. As used herein, the term "C1-C 18 alkoxyalkyl" refers to an alkyl group having an alkoxy substituent as defined above and containing a total of from 1 to 18 carbon atoms in the (alkyl-O-alkyl) moiety. Such groups include methoxymethyl (-CH2OCH3), 2-methoxyethyl (-CH2CH2OCH3), and 2-ethoxyethyl. Similarly, as used herein, the term "C7-C 18 alkoxyaryl" refers to an aryl group having an alkoxy substituent as defined above, with the moiety (aryl-O-alkyl) having a total of from 7 to 18 carbon atoms.

[0045] As used herein, the term "C2-C4 alkylene" is defined as a saturated divalent hydrocarbon group having from 2 to 4 carbon atoms.

[0046] "C3-C 18The term "cycloalkyl" is understood to mean a saturated monocyclic or polycyclic hydrocarbon group having 3 to 18 carbon atoms. In the present invention, such a cycloalkyl group may be unsubstituted or substituted with one or more halogens. When applicable to a given moiety (R), the allowable range of one or more non-halogen substituents within the cycloalkyl group is described in the specification.

[0047] Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantane, and norbornane.

[0048] As used herein, the "C6-C 18 aryl" group, alone or as part of a larger moiety such as an "aralkyl group", refers to monocyclic, bicyclic, and tricyclic ring systems, where the monocyclic ring system is aromatic or at least one ring in the bicyclic or tricyclic ring system is aromatic. The bicyclic and tricyclic ring systems include benzo-fused 2- to 3-membered carbon rings. In the present invention, such an aryl group may be unsubstituted or substituted with one or more halogens. When applicable to a given moiety (R), the allowable range of one or more non-halogen substituents within the aryl group is described herein. Exemplary aryl groups include phenyl, (C1-C4)alkylphenyl (such as tolyl and ethylphenyl), indenyl, naphthalenyl, tetrahydronaphthalenyl, tetrahydroindenyl, tetrahydroanthracenyl, and anthracenyl. It is also noted that the phenyl group is preferred.

[0049] As used herein, "C2-C 20"Alkenyl" refers to a hydrocarbyl group having 2 to 20 carbon atoms and at least one unit of ethylenic unsaturation. The alkenyl group may be straight-chain, branched-chain or cyclic, and may optionally be substituted with one or more halogens. When applicable to a given moiety (R), the tolerance range of one or more non-halogen substituents within the alkenyl group is described herein. The term "alkenyl" also includes groups having "cis" and "trans" configurations, or "E" and "Z" configurations, as understood by those skilled in the art. However, generally, the selection of unsubstituted alkenyl groups containing 2 to 10 (C 2-10 ) or 2 to 8 (C 2-8 ) carbon atoms is noted. Examples of said C2-C 12 alkenyl groups include, but are not limited to: -CH=CH2; -CH=CHCH3; -CH2CH=CH2; -C(=CH2)(CH3); -CH=CHCH2CH3; -CH2CH=CHCH3; -CH2CH2CH=CH2; -CH=C(CH3)2; -CH2C(=CH2)(CH3); -C(=CH2)CH2CH3; -C(CH3)=CHCH3; -C(CH3)CH=CH2; -CH=CHCH2CH2CH3; -CH2CH=CHCH2CH3; -CH2CH2CH=CHCH3; -CH2CH2CH2CH=CH2; -C(=CH2)CH2CH2CH3; -C(CH3)=CHCH2CH3; -CH(CH3)CH=CHCH; -CH(CH3)CH2CH=CH2; -CH2CH=C(CH3)2; 1-cyclopent-1-enyl; 1-cyclopent-2-enyl; 1-cyclopent-3-enyl; 1-cyclohex-1-enyl; 1-cyclohex-2-enyl; and 1-cyclohexyl-3-enyl.

[0050] As used herein, "alkylaryl" refers to an alkyl-substituted aryl group, both groups being defined as above. Further, as used herein, "aralkyl" means an alkyl group substituted with an aryl group as defined above.

[0051] As used herein, the term "hetero" refers to a group or moiety containing one or more heteroatoms such as N, O, Si, and S. Thus, for example, "heterocyclic" refers to a cyclic group having, for example, N, O, Si, or S as part of the ring structure. "Heteroalkyl", "heterocycloalkyl", and "heteroaryl" moieties are, respectively, the alkyl, cycloalkyl, and aryl groups defined above that contain N, O, Si, or S as part of their structure.

[0052] As used herein, the term "equivalent weight" means the molecular weight divided by the number of corresponding functional groups. Thus, "epoxy equivalent weight" (EEW) means the weight in grams of a resin containing 1 equivalent of epoxy.

[0053] As used herein, the term "epoxide" refers to a compound characterized by the presence of at least one cyclic ether group, i.e., a group in which an ether oxygen atom is bonded to two adjacent carbon atoms, thereby forming a cyclic structure. This term is intended to encompass monoepoxide compounds, polyepoxide compounds (having two or more epoxide groups), and epoxide-terminated prepolymers. The term "monoepoxide compound" means an epoxide compound having one epoxide group. The term "polyepoxide compound" means an epoxide compound having at least two epoxide groups. The term "diepoxide compound" means an epoxide compound having two epoxide groups.

[0054] Epoxides may be unsubstituted or may be inertly substituted. Exemplary inert substituents include chlorine, bromine, fluorine, and phenyl.

[0055] The molecular weights referred to in this specification can be measured by gel permeation chromatography (GPC) using polystyrene calibration standards as performed in accordance with ASTM 3536.

[0056] As used herein, the term softening point (°C) as used with respect to the waxes herein is the Ring & Ball softening point and is measured in accordance with ASTM E28 unless otherwise specified.

[0057] Unless otherwise specified, the viscosity of the compositions described herein is measured using an Anton Paar viscometer, model MCR301, under standard conditions of 25 °C and 50% relative humidity (RH). The viscometer is calibrated once a year and inspected by service. The calibration is performed using special oils of known viscosities varying from 5,000 cps to 50,000 cps (shear rate s at parallel plates PP25 and 23 °C -1 ). Measurements of the compositions of the present invention are performed at different shear rates of 1.5 to 100 (s -1 ) using parallel plates PP25.

[0058] Detailed Description of the Invention First Component of Two - Component (2K) Composition The first component of the two - component (2K) composition necessarily includes a (meth)acrylate monomer, a copolymerizable acid, and an electrolyte.

[0059] (Meth)acrylate Monomer The first component of the composition typically contains a (meth)acrylate monomer in an amount of 20 - 80% by weight, based on the weight of the first component. The (meth)acrylate monomer preferably constitutes 30 - 60% by weight, for example, 35 - 50% by weight of the first component.

[0060] An amount exceeding 80% may have an adverse effect on the initial adhesiveness and peeling effect, while a small amount, mainly less than 20%, may lead to a decrease in the initial adhesiveness. Therefore, the amount of the (meth)acrylate monomer described above is preferred.

[0061] There is no intention to limit the (meth)acrylate esters useful in this specification, and it is considered that the (meth)acrylate monomer can be any ester of acrylic acid or methacrylic acid known in the art. That being said, exemplary (meth)acrylic monomers include, but are not limited to:

[0062] · C1-C 18 alkyl esters of meth(acrylic acid), such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate (all isomers), hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-dodecyl (meth)acrylate, and n-stearyl (meth)acrylate, etc.; · C3-C 18 cycloalkyl esters of meth(acrylic acid), such as cyclohexyl (meth)acrylate and isobornyl (meth)acrylate, etc.; · C6-C 18 aryl esters of meth(acrylic acid), such as phenyl (meth)acrylate and tolyl (meth)acrylate, etc.; · C7-C 24 aralkyl esters of meth(acrylic acid), such as benzyl (meth)acrylate, etc.; · C1-C 18 alkoxyalkyl esters of meth(acrylic acid), such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and 3-methoxybutyl (meth)acrylate, etc.; · fluorine-containing C1-C 18Alkyl esters, such as trifluoromethyl methyl (meth)acrylate, 2-trifluoromethyl ethyl (meth)acrylate, 2-perfluoroethyl ethyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutyl ethyl (meth)acrylate, 2-perfluoroethyl (meth)acrylate, perfluoromethyl (meth)acrylate, dipentafluoromethyl methyl (meth)acrylate, 2-perfluoromethyl-2-perfluoroethyl methyl (meth)acrylate, 2-perfluorohexyl ethyl (meth)acrylate, 2-perfluorodecyl ethyl (meth)acrylate, and 2-perfluorohexadecyl ethyl (meth)acrylate; · C1-C of (meth)acrylic acid 18 Hydroxyalkyl esters, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and pentaerythritol tri(meth)acrylate; · Di / polyesters of di / polyfunctional alcohols, such as ethylene glycol di(meth)acrylate, 1,3 or 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate; · C1-C of (meth)acrylic acid 18 Aminoalkyl esters, such as 2-aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and (meth)acryloxyethoxyethylamine; · C1-C of (meth)acrylic acid 18 Alkoxysilyl-containing alkyl esters, such as γ-(meth)acryloyloxypropyltrimethoxysilane; · Ethylene oxide or propylene oxide adducts of (meth)acrylic acid; and · (Meth)acrylate esters formed by alcohols having other functional groups, such as tetrahydrofurfuryl (meth)acrylate.

[0063] In order to achieve perfection, it is not excluded that the first component of the composition comprises a macromonomer component consisting of one or more oligomers selected from the group consisting of urethane (meth)acrylate, polyester (meth)acrylate, and polyether (meth)acrylate. However, although it can be monofunctional or polyfunctional with respect to the polymerizable (meth)acrylate functional group, such oligomeric compounds based on urethane, ester, and ether subunits of the repeating structure should usually not be constituted by more than 30% by weight of the total (meth)acrylate monomers in the above-mentioned first component.

[0064] As is known in the art, urethane (meth)acrylate oligomers can be prepared by the reaction of a polyfunctional (meth)acrylate having a hydroxyl group with the polyisocyanate defined above herein. In particular, the polyfunctional (meth)acrylate having a hydroxyl group can be selected from the group consisting of 2-hydroxyethyl (meth)acrylate; 2-hydroxyisopropyl (meth)acrylate; 4-hydroxybutyl (meth)acrylate; hydroxyethyl caprolactone (meth)acrylate; pentaerythritol tri(meth)acrylate; pentaerythritol tetra(meth)acrylate; dipentaerythritol penta(meth)acrylate; dipentaerythritol hexa(meth)acrylate; and combinations thereof.

[0065] A suitable polyester (meth)acrylate oligomer is obtained by reacting (meth)acrylic acid with a polyester prepared from a polybasic acid or its anhydride and a polyhydric alcohol. Examples of polybasic acids include, but are not limited to, phthalic acid; succinic acid; adipic acid; glutaric acid; sebacic acid; isosebacic acid; tetrahydrophthalic acid; hexahydrophthalic acid; dimer acid; trimellitic acid; pyromellitic acid; pimelic acid; and azelaic acid. Examples of polyhydric alcohols include, but are not limited to, 1,6 - hexanediol; diethylene glycol; 1,2 - propylene glycol; 1,3 - butylene glycol; neopentyl glycol; dipropylene glycol; polyethylene glycol; and polypropylene glycol.

[0066] As is known in the art, a polyether (meth)acrylate oligomer can be obtained by a transesterification reaction between a polyether and a (meth)acrylate ester such as ethyl methacrylate. Exemplary polyethers include polyethers obtained from ethoxylated or propoxylated trimethylolpropane, pentaerythritol, etc., or polyethers obtained by polyetherification of 1,4 - propanediol, etc.

[0067] In a preferred embodiment, the first component comprises at least one (meth)acrylate monomer selected from the group consisting of: methyl (meth)acrylate; ethyl (meth)acrylate; n-propyl (meth)acrylate; isopropyl (meth)acrylate; n-butyl (meth)acrylate; isobutyl (meth)acrylate; tert-butyl (meth)acrylate; n-pentyl (meth)acrylate; n-hexyl (meth)acrylate; cyclohexyl (meth)acrylate; n-heptyl (meth)acrylate; n-octyl (meth)acrylate; 2-ethylhexyl-(meth)acrylate; nonyl (meth)acrylate; decyl (meth)acrylate; dodecyl (meth)acrylate; phenyl (meth)acrylate; tolyl (meth)acrylate; benzyl (meth)acrylate; 2-methoxyethyl (meth)acrylate; 3-methoxybutyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate; 2-hydroxypropyl (meth)acrylate; stearyl (meth)acrylate; glycidyl (meth)acrylate; isobornyl (meth)acrylate; 2-aminoethyl (meth)acrylate; γ-(meth)acryloyloxypropyltrimethoxysilane; (meth)acrylic acid-ethylene oxide adduct; trifluoromethylmethyl (meth)acrylate; 2-trifluoromethylethyl (meth)acrylate; 2-perfluoroethylethyl (meth)acrylate; 2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate; 2-perfluoroethylethyl (meth)acrylate; perfluoromethyl (meth)acrylate; dipentafluoroethylmethyl (meth)acrylate; 2-perfluoromethyl-2-perfluoroethylmethyl (meth)acrylate; 2-perfluorohexylethyl (meth)acrylate; 2-perfluorodecylethyl (meth)acrylate; 2-perfluorohexadecylethyl (meth)acrylate; ethoxylated trimethylolpropane triacrylate; trimethylolpropane trimethacrylate; dipentaerythritol monohydroxypentaacrylate; pentaerythritol triacrylate; ethoxylated trimethylolpropane triacrylate; 1,6-hexanediol diacrylate;Neopentyl glycol diacrylate; pentaerythritol tetraacrylate; 1,2-butylene glycol diacrylate; trimethylolpropane ethoxylate tri(meth)acrylate; glyceryl propoxylate tri(meth)acrylate; trimethylolpropane tri(meth)acrylate; dipentaerythritol monohydroxy penta(meth)acrylate; tripropylene glycol di(meth)acrylate; neopentyl glycol propoxylate di(meth)acrylate; 1,4-butanediol di(meth)acrylate; triethylene glycol di(meth)acrylate; butylene glycol di(meth)acrylate; and ethoxylated bisphenol A di(meth)acrylate.;

[0068] Good results were obtained when the first component contained at least one (meth)acrylate monomer selected from the group consisting of methyl (meth)acrylate, ethyl (meth)acrylate, isobornyl (meth)acrylate, ethoxylated trimethylolpropane triacrylate and trimethylolpropane triacrylate. The use of methyl methacrylate in the first component is particularly preferred.

[0069] The above (meth)acrylate monomers are preferred because the size of the monomers results in the formation of an ideal polymer network, which is thought to increase ion transport.

[0070] In the art, it is known that incorporating certain additional non-polymerizable functional groups into (meth)acrylate monomers can improve the surface adhesion of the polymers derived therefrom. In this regard, anhydride, phosphate or phosphonate functional groups may be mentioned, and (meth)acrylate monomers having such functional groups may be used as the first component (first component) of the composition of the present invention. A list of such phosphorus compounds is described in U.S. Patent No. 4,223,115. Exemplary monomers include 2-monomethacryloxyethyl phosphate; bis(2-methacryloxyethyl) phosphate; 2-acryloyloxyethyl phosphate; bis-(2-acryloyloxyethyl) phosphate; methyl-(2-methacryloyloxyethyl) phosphate; ethyl methacryloyloxyethyl phosphate; methylacryloyloxyethyl phosphate; ethylacryloyloxyethyl phosphate; 2-hydroxyethyl methacrylate phosphate; 10-[(2-methylprop-2-onyl)oxy]decyl dihydrogen phosphate (10-methacryloyloxydecyl dihydrogen phosphate), and 4-methacryloxyethyl trimellitic anhydride.

[0071] Copolymerizable acid As described above, the first component of the composition contains a copolymerizable acid typically used in an amount of 0.5 to 20% by weight based on the weight of the first component: the copolymerizable acid may preferably constitute 5 to 15% by weight, for example 6 to 12% by weight of the first component. For the sake of completeness, such monomers are typically used in the form of the free acid, but the fact that the constituent acid groups of the monomers are partially or completely neutralized with a suitable base is not excluded if this does not impair their participation in the copolymerization.

[0072] The copolymerizable acid is considered to improve the curing rate and metal adhesiveness of the composition. The above amount of the copolymerizable acid is preferably such that an amount exceeding 20% by weight based on the weight of the first component may cause corrosion problems and gas generation, while an amount less than 0.5% by weight based on the weight of the first component may lead to incomplete curing and thus may reduce the initial adhesion properties.

[0073] Without intending to limit the present invention, the copolymerizable acid monomer is preferably selected from ethylenically unsaturated carboxylic acids; ethylenically unsaturated sulfonic acids; and vinylphosphonic acid. Suitable ethylenically unsaturated sulfonic acids are, for example, vinylsulfonic acid, styrenesulfonic acid, and acrylamidomethylpropanesulfonic acid.

[0074] Preferably, the copolymerizable acid of this component comprises or consists of ethylenically unsaturated carboxylic acids selected from the group consisting of α,β-monoethylenically unsaturated monocarboxylic acids; α,β-monoethylenically unsaturated dicarboxylic acids; C1-C6 alkyl half-esters of α,β-monoethylenically unsaturated dicarboxylic acids; α,β-monoethylenically unsaturated tricarboxylic acids; and C1-C6 alkyl esters of α,β-monoethylenically unsaturated tricarboxylic acids having at least one free carboxylic acid group; and mixtures thereof. In particular, the copolymerizable acid of this component comprises or consists of at least one acid selected from methacrylic acid, acrylic acid, itaconic acid, maleic acid, aconitic acid, crotonic acid, and fumaric acid.

[0075] The present invention can be copolymerized with (meth)acrylate monomers, such as styrene monomers like styrene, vinyltoluene, α-methylstyrene, and chlorostyrene; fluorine-containing vinyl monomers like perfluoroethylene, perfluoropropylene, and fluorinated vinylidene; silicon-containing vinyl monomers like vinyltrimethoxysilane and vinyltriethoxysilane; maleimide monomers like maleimide, methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide, hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide, phenylmaleimide, and cyclohexylmaleimide; nitrile group-containing vinyl monomers like acrylonitrile and methacrylonitrile; amide group-containing vinyl monomers like acrylamide and methacrylamide; vinyl esters like vinyl acetate, vinyl propionate, vinyl pivalate, vinyl benzoate, and vinyl cinnamate; alkenes like ethylene and propylene; conjugated dienes like butadiene and isoprene; and vinyl chloride, vinylidene chloride, allyl chloride, and allyl alcohol. It should be noted that the presence of vinyl monomers selected from the group consisting of these is not excluded in the first component. However, when included, such vinyl comonomers preferably constitute less than 40% by weight, preferably less than 20% by weight or less than 10% by weight, based on the total weight of the copolymerizable acid monomers.

[0076] Electrolyte The first component of the composition contains 0.5 to 20% by weight of an electrolyte, based on the weight of the first part, and the electrolyte may preferably constitute 5 to 15% by weight of the first component, such as 6 to 12% by weight. These amounts are preferred because when the amount of the electrolyte exceeds 20% by weight based on the weight of the first component, a good peeling effect may be obtained, but curing may be incomplete, and thus the initial adhesion properties may be adversely affected. Conversely, when the amount is less than 0.5% by weight based on the weight of the first component, the peeling effect may be impaired.

[0077] The electrolyte is of formula (I) or formula (II): JPEG2025520529000004.jpg40122[wherein, R 1 , R 2 , R 3 , R 4 and R 5 are independently selected from hydrogen, C1-C 18 alkyl, C3-C 18 cycloalkyl, C6-C 18 aryl, C7-C 24 aralkyl, C2-C 20 alkenyl, -C(O)R q , -C(O)OH, -CN or -NO2, and R q is C1-C6 alkyl, and X− is an JPEG2025520529000005.jpg28124counteranion selected from the group consisting of (wherein, R a and R b are independently selected from hydrogen, C1-C 12 alkyl, C5-C 12 cycloalkyl, C5-C 12 heterocycloalkyl, C6-C 18 aryl or C5-C 18 heteroaryl)]] contains or consists of at least one salt as described in

[0078] For the sake of completeness, in formula (I) and formula (II), the terms C1-C n alkyl, C3-C n cycloalkyl, C6-C 18 aryl, C7-C 24 aralkyl, C2-C 20 alkenyl explicitly include groups in which one or more hydrogen atoms are substituted with a halogen atom (e.g., C1-C 18 haloalkyl) or a hydroxyl group (e.g., C1-C 18 hydroxyalkyl). In particular, R 1 , R 2 , R 3 , R 4 and R 5 are hydrogen, C1-C18 alkyl, C1-C 18 haloalkyl, C1-C 18 hydroxyalkyl or C3-C 18 cycloalkyl, preferably independently selected. For example, R 1 , R 2 , R 3 , R 4 and R 5 may be independently selected from hydrogen, C1-C 18 alkyl or C1-C 18 haloalkyl.

[0079] Regarding the carboxylic acid imide, bis(sulfonyl)imide or sulfonylimide counter anion (X-) of formula (I) or formula (II), R a and R b are preferably independently selected from hydrogen, C1-C 12 alkyl or C1-C 12 haloalkyl. For example, R a and R b may be independently selected from hydrogen, C1-C8 alkyl or C1-C8 haloalkyl, or R a and R b may be independently selected from hydrogen, C1-C4 alkyl or C1-C4 haloalkyl. A particularly preferred counter anion (X-) is bis(trifluoromethylsulfonyl)imide.

[0080] The electrolyte in the first part is preferably 1-methylimidazolium bis(trifluoromethylsulfonyl)imide; 3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-propyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide; 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide; 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; tetraethylphosphonium bis(trifluoromethylsulfonyl)imide; tetrabutylphosphonium bis(trifluoromethylsulfonyl)imide; tridecyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide and mixtures thereof. It can be particularly preferred to use at least one of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide and trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide.

[0081] The presence of compatible electrolyte compounds not conforming to formula (I) or formula (II) in the electrolyte is not excluded. However, the compounds of formula (I) or formula (II) need to constitute at least 90% by weight, preferably at least 95%, more preferably at least 99% by weight, and most preferably 100% by weight of the electrolyte.

[0082] Second component of the two-component (2K) composition The second component of the two-component composition includes a first curing agent for the monomer of the first component, a second curing agent for the monomer of the first component, wax, and a solubilizing agent.

[0083] First curing agent As described above, the second component of the composition typically includes a first curing agent to be used in an amount of 5 to 40% by weight based on the weight of the second component. The first curing agent may preferably constitute 10 to 40% by weight, for example, 20 to 40% by weight of the second component.

[0084] When the amount exceeds 40% by weight based on the weight of the second component, the first curing agent may be excessive, and undesirable reactions may adversely affect the properties of the composition. On the other hand, when the amount is small, mainly less than 5% by weight, curing may be incomplete and the initial adhesiveness may be inferior. Therefore, the above amount of the first curing agent is preferred.

[0085] In an important aspect, the first curing agent comprises or consists of at least one free radical initiator that decomposes under the action of heat to provide free radicals. Exemplary thermally activated free radical initiators include peroxides such as ketone peroxides; hydroperoxides; peroxycarbonates; peracetic acid; azo compounds such as 2,2'-azobisisobutyronitrile (AIBN) or 2,2'-azobis(2,4-dimethylpentanenitrile), 4,4'-azobis(4-cyanovaleric acid), or 1,1'-azobis(cyclohexanecarbonitrile); tetrazine; and persulfate compounds such as potassium persulfate. A free radical initiator that is solid at room temperature is preferred. Independently of this, or in addition to what has been described as preferred, it is desirable that the free radical initiator has a half-life of at least 10 hours at a temperature of 60°C.

[0086] Certain peroxides, such as dialkyl and diaryl peroxides, have been disclosed as useful curing agents, inter alia, in U.S. Patent No. 3,419,512 (Lees) and U.S. Patent No. 3,479,246 (Stapleton), and are indeed useful herein. However, hydroperoxides also represent an important class of curing agents for the present invention. In this regard, hydrogen peroxide itself can be used, but it is preferred to use organic hydroperoxides. For completeness, the definition of hydroperoxides includes materials such as organic peroxides or organic peresters that decompose or hydrolyze in situ to form organic hydroperoxides. Examples of such peroxides and peresters include cyclohexyl and hydroxycyclohexyl peroxides and t-butyl perbenzoate, respectively.

[0087] Without intending to limit the present invention, representative hydroperoxide compounds generally have the formula:

Chemical formula

[0088] As a first curing agent, exemplary compounds that can be used alone or in combination include cumene hydroperoxide (CHP); paramethane hydroperoxide; t-butyl hydroperoxide (TBH); t-butyl perbenzoate; t-butyl peracetate; t-amyl hydroperoxide; 1,2,3,4-tetramethylbutyl hydroperoxide; lauryl peroxide; benzoyl peroxide (dibenzoyl peroxide, C 14 H 10O4 (also known as CAS No. 94-36-0); 1,3-bis(t-butylperoxyisopropyl)benzene; diacetyl peroxide; butyl 4,4-bis(t-butylperoxy)valerate; p-chlorobenzoyl peroxide; t-butyl cumyl peroxide; di-t-butyl peroxide; dicumyl peroxide; 2,5-dimethyl-2,5-di-t-butylperoxyhexane; 2,5-dimethyl-2,5-di-t-butyl-peroxyhex-3-yne; and 4-methyl-2,2-di-t-butylperoxypentane may be mentioned.

[0089] Preferably, the first curing agent is a peroxide or hydroperoxide compound selected from the group consisting of tert-butyl peroxide, tert-butyl perbenzoic acid, cumene hydroperoxide, tert-butyl peroxybenzoic acid, diacetyl peroxide, benzoyl peroxide, tert-butyl peracetic acid, lauryl peroxide, and mixtures thereof, and it is noted that benzoyl peroxide is particularly preferred.

[0090] When the first curing agent is an oxidizing agent (such as the aforementioned peroxides and hydroperoxide compounds), the composition may further contain an activator. When combined in appropriate proportions, the oxidizing agent and the activator (reducing agent) generate polymerization-initiating radicals even under mild conditions without an auxiliary energy source. Either the oxidizing agent alone or both the oxidizing agent and the reducing agent can generate polymerization-initiating radicals.

[0091] Exemplary activators or reducing agents may be selected from the group consisting of alkali metal sulfites, alkali metal bisulfites, alkali metal metabisulfites, formaldehyde sulfoxylate, alkali metal salts of aliphatic sulfinic acids, alkali metal hydrogen sulfides, salts of polyvalent metals, especially Co(II) salts and Fe(II) salts such as iron(II) sulfate, ammonium iron(II) sulfate, or iron(II) phosphate, dihydroxymaleic acid, benzoin, ascorbic acid, reducing amines, especially N,N-bis(2-hydroxyethyl)-p-toluidine (diethanol-p-toluidine, DE-p-T), 2-(4-dimethylaminophenyl)ethyl alcohol (DMAPE), 4-tert-butyldimethylaniline, 3-dimethylaminobenzoic acid, 4-dimethylaminobenzoic acid, ethyl 4-dimethylaminobenzoate (EDMAB), 2-ethylhexyl 4-dimethylaminobenzoate and aromatic tertiary amines such as 4-dimethylaminobenzoate, and reducing saccharides such as sorbose, glucose, fructose and / or dihydroxyacetone.

[0092] The activator (reducing agent) is generally included in the first component together with the polymerizable species. However, it is not precluded from adding the activator to the second component immediately before bringing the first and second components into contact.

[0093] The second curing agent As described above, the second component of the composition contains a second curing agent typically used in an amount of 0.01 to 2% by weight, based on the weight of the second component. The second curing agent may preferably constitute 0.01 to 1% by weight, for example, 0.01 to 0.5% by weight of the second component.

[0094] In an important aspect, the second curing agent comprises, or consists of, at least one compound that is a salt or complex of a transition metal, where the transition metal is selected from the group consisting of Fe, Co, V, Ti, Mn, Cu, Sn, Cr, Ni, Mo, Ge, Sr, Pd, Pt, Nb, Sb, Re, Os, Ir, Pt, Au, Hg, Te, Rb, and Bi, and is preferably selected from the group consisting of Fe, Co, V, Mn, and Cu in particular. It is noted that both Fe(II) complexes and Fe(III) complexes can be used.

[0095] It has been shown to be advantageous for the second agent to comprise, or consist of, at least one iron compound selected from the group consisting of iron carboxylates, 1,3-dioxoiron complexes; ammonium ferricyanide; and dicyclopentadienyliron complexes. Exemplary iron carboxylates in this regard include iron lactate, iron naphthenate, iron 2-ethylhexanoate (iron octanoate), iron formate, iron acetate, iron propionate, iron butyrate, iron pentanoate, iron hexanoate, iron heptanoate, iron nonanoate, iron decanoate, iron neodecanoate, and iron dodecanoate. Exemplary 1,3-dioxoiron complexes include iron acetylacetonate, and iron complexes of acetylacetone, benzoylacetone, dibenzoylmethane, and acetoacetates such as diethylacetoacetamide, dimethylacetoacetamide, dipropylacetoacetamide, dibutylacetoacetamide, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, and butyl acetoacetate. Examples of dicyclopentadienyliron complexes are complexes containing iron and two substituted or unsubstituted cyclopentadienyl ligands, where any substituent on the cyclopentadienyl ring is selected from the group consisting of C1-C 12 alkyl, C6-C 18 aryl, and C7-C 18 aralkyl groups. A specific example of a dicyclopentadienyliron complex is ferrocene (bis(η5-cyclopentadienyl)iron).

[0096] Among the second curing agents, or as further exemplary transition metal compounds that can be used as the second curing agent, salts and complexes of copper, cobalt, vanadium, and manganese may be specifically mentioned. In the present specification, cobalt compounds can be used as transition metals without legislative and toxicity problems because the amount used is small. Suitable counter anions present in the salts include halides; nitrates; sulfates; sulfonates; phosphates, phosphonates; oxides; or carboxylates such as lactates, 2-ethylhexanoates, acetates, propionates, butyrates, oxalates, laurates, oleates, linoleates, palmitates, stearates, acetylacetonates, octanoates, nonanoates, heptanoates, neodecanoates, or naphthenates.

[0097] Wax The presence of wax in the first component is not excluded, but the composition of the present invention is characterized in that the second component contains at least one wax in an amount of 5 to 30% by weight based on the weight of the components. The wax may constitute, for example, 5 to 20% by weight or 5 to 15% by weight of the second component. When the first component and the second component of the composition are mixed, the at least one wax serves to limit the evaporation of the monomers present, particularly (meth)acrylate monomers.

[0098] Although not intended to limit the present invention, the waxes useful in the present invention should have a softening point of 50 to 150 °C and include petroleum waxes such as polyethylene, paraffin wax, and microcrystalline wax having a number average molecular weight (Mn) of 500 to 7500, synthetic waxes made by polymerizing carbon monoxide and hydrogen such as Fischer-Tropsch wax, polyolefin waxes including functionalized polyolefin waxes such as maleated polyethylene, maleated polypropylene, and maleated poly(ethylene-co-propylene), and may include one or more of hydrogenated animal oils, fish oils, or vegetable oils.

[0099] Solubilizer The second component of the two-component (2K) composition necessarily contains a solubilizer that conventionally exists in an amount of 20 to 60% by weight based on the weight of the second component. Preferably, the solubilizer constitutes 30 to 60% by weight, for example, 40 to 60% by weight of the second component. If the amount of the solubilizer exceeds 60% by weight based on the receipt of the second component, the adhesiveness and curability of the composition may be adversely affected.

[0100] The solubilizer has a function of promoting the miscibility of electrolytes in the adhesive composition formed upon mixing of the two components. The solubilizer may or may not form part of the polymer matrix formed upon curing of the adhesive composition, but plays a role in promoting ion migration therein. The solubilizer itself is preferably a polar compound and desirably should be liquid at room temperature.

[0101] In a first embodiment, the solubilizer comprises or consists of one or more liquid epoxy resins. Epoxy resins used herein can include monofunctional epoxy resins, polyfunctional (multi- or polyfunctional) epoxy resins, and combinations thereof. The epoxy resin may be a pure compound, but may also be a mixture of epoxy-functional compounds such as a mixture of compounds having different numbers of epoxy groups per molecule. The epoxy resin may be saturated or unsaturated, aliphatic, alicyclic, aromatic or heterocyclic, and may be substituted. Further, the epoxy resin may be a monomer or a polymer.

[0102] Without intending to limit the present invention, exemplary monoepoxide compounds include the following. Alkylene oxides; epoxy-substituted alicyclic hydrocarbons such as cyclohexene oxide, vinylcyclohexene monooxide, (+)-cis-limonene oxide, (+)-cis,trans-limonene oxide, (-)-cis,trans-limonene oxide, cyclooctene oxide, cyclododecene oxide, and α-pinene oxide; epoxy-substituted aromatic hydrocarbons; monoepoxy-substituted alkyl ethers of monohydric alcohols or phenols such as glycidyl ethers of aliphatic, alicyclic, and aromatic alcohols; monoepoxy-substituted alkyl esters of monocarboxylic acids such as glycidyl esters of aliphatic, alicyclic, and aromatic monocarboxylic acids; monoepoxy-substituted alkyl esters of polycarboxylic acids in which other carboxy groups are esterified with alkanols; alkyl and alkenyl esters of epoxy-substituted monocarboxylic acids; epoxyalkyl ethers of polyhydric alcohols in which other OH groups are esterified or etherified with carboxylic acids or alcohols; and monoesters of polyhydric alcohols and epoxy monocarboxylic acids in which other OH groups are esterified or etherified with carboxylic acids or alcohols.

[0103] By way of example, the following glycidyl ethers may be mentioned as monoepoxide compounds suitable for use herein. Methyl glycidyl ether; ethyl glycidyl ether; propyl glycidyl ether; butyl glycidyl ether; pentyl glycidyl ether; hexyl glycidyl ether; cyclohexyl glycidyl ether; octyl glycidyl ether; 2-ethylhexyl glycidyl ether; allyl glycidyl ether; benzyl glycidyl ether; phenyl glycidyl ether; 4-tert-butylphenyl glycidyl ether; 1-naphthyl glycidyl ether; 2-naphthyl glycidyl ether; 2-chlorophenyl glycidyl ether; 4-chlorophenyl glycidyl ether; 4-bromophenyl glycidyl ether; 2,4,6-trichlorophenyl glycidyl ether; 2,4,6-tribromophenyl glycidyl ether; pentafluorophenyl glycidyl ether; o-cresyl glycidyl ether; m-cresyl glycidyl ether; and p-cresyl glycidyl ether.

[0104] In certain embodiments, the monoepoxide compound conforms to formula (III) below herein. TIFF2025520529000007.tif35149[wherein R w 、R x 、R y and R z may be the same or different and are independently selected from hydrogen, a halogen atom, a C1-C8 alkyl group, a C3-C 10 cycloalkyl group, a C2-C 12 alkenyl, a C6-C 18 aryl group or a C7-C 18 aralkyl group, provided that at least one of R y and R z is not hydrogen.]

[0105] R w 、R x and R y are hydrogen, and R zis preferably a phenyl group or a C1-C8 alkyl group, more preferably a C1-C4 alkyl group.

[0106] In view of these embodiments, exemplary monoepoxides include ethylene oxide, 1,2-propylene oxide (propylene oxide); 1,2-butylene oxide; cis-2,3-epoxybutane; trans-2,3-epoxybutane; 1,2-epoxypentane; 1,2-epoxyhexane; 1,2-heptylene oxide; decene oxide; butadiene oxide; isoprene oxide; and styrene oxide.

[0107] In the present invention, mention is made of using at least one monoepoxide compound selected from the group consisting of ethylene oxide; propylene oxide; cyclohexene oxide; (+)-cis-limonene oxide (+)-cis, trans-limonene oxide; (-) cis, trans-limonene oxide; cyclooctene oxide; and cyclododecene oxide.

[0108] Again, without intending to limit the present invention, suitable polyepoxy compounds can be liquids, solids, or solutions in solvents. Further, such polyepoxide compounds should have an epoxide equivalent of 100 to 700 g / eq, for example, 120 to 320 g / eq. Further, generally, diepoxide compounds having an epoxide equivalent of less than 500 g / eq, and further less than 400 g / eq are preferred. This is mainly from the perspective of cost, because in their production, etc., low molecular weight epoxy resins require more limited treatment in purification.

[0109] Examples of types or groups of polyepoxy compounds that can be polymerized in the present invention include glycidyl ethers of polyhydric alcohols and polyhydric phenols; glycidyl esters of polycarboxylic acids; and epoxidized polyethylene-based unsaturated hydrocarbons, esters, ethers, and amides.

[0110] Suitable diglycidyl ether compounds can be inherently aromatic, aliphatic, or alicyclic and can thus be derived from dihydric phenols and dihydric alcohols. And useful classes of such diglycidyl ethers are diglycidyl ethers of aliphatic and alicyclic diols such as 1,2-ethanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,12-dodecanediol, cyclopentanediol, and cyclohexanediol; bisphenol A-based diglycidyl ethers; bisphenol F diglycidyl ethers; polyalkylene glycol-based diglycidyl ethers, particularly, polypropylene glycol diglycidyl ether; and polycarbonate diol-based glycidyl ethers.

[0111] Further exemplary polyepoxy compounds include, but are not limited to, glycerol polyglycidyl ether; trimethylolpropane polyglycidyl ether; pentaerythritol polyglycidyl ether; diglycerol polyglycidyl ether; polyglycerol polyglycidyl ether; and sorbitol polyglycidyl ether.

[0112] The glycidyl esters of polycarboxylic acids useful in the present invention are derived from polycarboxylic acids containing at least two carboxylic acid groups and no other groups reactive with epoxide groups. The polycarboxylic acids can be aliphatic, alicyclic, aromatic and heterocyclic. Preferred polycarboxylic acids contain 18 or fewer carbon atoms per carboxylic acid group, and suitable examples thereof include oxalic acid; sebacic acid; adipic acid; succinic acid; pimelic acid; suberic acid; glutaric acid; dimer acids and trimer acids of unsaturated fatty acids, such as dimer acids and trimer acids of linseed fatty acids; phthalic acid; isophthalic acid; terephthalic acid; trimellitic acid; trimesic acid; phenylenediacetic acid; chlorendic acid; hexahydrophthalic acid, particularly hexahydroorthophthalic acid (1,2-cyclohexanedicarboxylic acid); diphenic acid; naphthalic acid; polyacid terminal esters of dibasic acids and aliphatic polyols; polymers and copolymers of (meth)acrylic acid; and crotonic acid, but are not limited thereto.

[0113] Other suitable diepoxides that may be further mentioned include diepoxides of double unsaturated fatty acids C1-C 18 diepoxides of alkyl esters; butadiene diepoxide; polybutadiene diglycidyl ether; vinylcyclohexene diepoxide; and limonene diepoxide.

[0114] Examples of preferred polyepoxide compounds include bisphenol A epoxy resins such as DER™ 331, DER™ 332, DER™ 383, JER™ 828, and Epotec YD128; bisphenol F epoxy resins such as DER™ 354; bisphenol A / F epoxy resin blends such as DER™ 353; aliphatic glycidyl ethers such as DER™ 736; polypropylene glycol diglycidyl ethers such as DER™ 732; epoxy novolak resins such as DEN™ 438; brominated epoxy resins such as DER™ 542; castor oil triglycidyl ether such as ERISYS™ GE-35H; polyglycerol-3-polyglycidyl ether such as ERISYS™ GE-38; sorbitol glycidyl ether such as ERISYS™ GE-60; and bis(2,3-epoxypropyl) cyclohexane-1,2-dicarboxylate available as Lapox Arch-11. In particular, the selection of a solubilizer comprising or consisting of a bisphenol A epoxy resin is noted.

[0115] When the solubilizer of the second component of the composition is based on one or more epoxy resins, the present invention does not exclude the solubilizer further comprising one or more cyclic compounds selected from the group consisting of oxetane, cyclic carbonate, cyclic anhydride, and lactone. The following cited disclosures may be useful in disclosing suitable cyclic carbonate functional compounds: U.S. Patent No. 3,535,342, U.S. Patent No. 4,835,289, U.S. Patent No. 4,892,954, British Patent Application Publication No. 1,485,925, and European Patent Application Publication No. 0119840. However, such additional cyclic compounds preferably constitute less than 20% by weight, more preferably less than 10% by weight or less than 5% by weight, based on the total weight of the epoxide compound.

[0116] In another embodiment not intended to mutually exclude the above, the solubilizer of the second component is liquid at room temperature and comprises at least one polymer selected from the group consisting of polyphosphazene; polymethylene sulfide; polyoxyalkylene glycol; and polyethyleneimine. Particular mention may be made of the selection of polyoxy(C2-C3)alkylene glycols having a weight average molecular weight of 350 to 10,000 g / mol, for example 500 to 5,000 g / mol.

[0117] Reinforcing agent The composition of the present invention comprises a reinforcing agent which may be present in either or both of its first component (A) and second component (B). However, it is preferred that the first component (A) contains a reinforcing agent. Separately, the presence of a reinforcing agent in the composition is advantageous for the peeling of the cured adhesive. Without wishing to be bound by theory, the reinforcing agent promotes phase separation in the cured adhesive under the application of a potential.

[0118] Preferably, the reinforcing agent is included in the composition in an amount of 5 to 40% by weight, for example 10 to 40% by weight or 20 to 40% by weight, based on the total weight of the composition. These amounts of the reinforcing agent are preferred because amounts exceeding 40% by weight may result in insufficient adhesion properties, while amounts less than 5% by weight may result in insufficient peeling effect and the composition may become too flexible.

[0119] Good results were obtained when the composition of the present invention comprised at least one reinforcing agent selected from the group consisting of non-reactive elastomers and core-shell rubber particles. It is preferred that a non-reactive elastomer is present in the composition. It is particularly noted that it is particularly preferred to include a reinforcing agent comprising or consisting of at least one non-reactive elastomer in the first component of the composition.

[0120] The term "non-reactive" as applied to the elastomeric component of the present composition means that the polymer does not contain activated double bonds capable of free radical polymerization. The term "elastomeric" is defined as having the ability of a polymer to return to approximately its initial length after being stretched to a breaking point or less when provided as a strip.

[0121] Examples of non-reactive elastomers useful in the present invention include, but are not limited to: i) elastomeric homopolymers of dienes, such as homopolymers of 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2-chloro-1,3-butadiene (chloroprene), 2,3-dimethyl-1,3-butadiene, 1,4-dimethyl-1,3-butadiene, 1,3-piperylene, 1,3-hexadiene, 2-methyl-1,3-pentadiene, 2-methyl-3-butyl-1,3-butadiene, and 2,3-diethyl-1,3-butadiene; ii) elastomeric copolymers of dienes and at least one modified ethylenically unsaturated comonomer, such as ethylene, propylene, isobutylene, styrene, α-(C1-C4-alkyl)styrene, (meth)acrylonitrile, and methyl methacrylate, wherein the comonomer typically may constitute 5 to 40% by weight of the copolymer; iii) (meth)acrylic elastomeric polymers, such as all acrylic thermoplastic elastomers (TPE); iv) natural rubber; and v) polyethylene, polypropylene, and ethylene-propylene copolymers.

[0122] Specific examples of non-reactive elastomers include the following: ethylene / propylene / diene terpolymers; (meth)acrylonitrile-butadiene copolymers; (meth)acrylonitrile-styrene copolymers; (meth)acrylonitrile-butadiene-styrene copolymers; styrene-isoprene-styrene copolymers; styrene-butadiene-styrene copolymers; and A-B-A triblock copolymers composed of C1-C8 alkyl (meth)acrylates having different glass transition temperatures (Tg) for blocks A and B, for example, PMMA-PnBA-PMMA and PMMA-P(nBA / 2-EHA)-PMMA triblock copolymers based on methyl (meth)acrylate (MMA), n-butyl acrylate (nBA), and 2-ethylhexyl acrylate (2-EHA). Examples of these commercially available products include EUROPRENE (registered trademark) available from Enichem Elastomers Americas, Inc., Hypro 200X 168LC VTB available from Huntsman, Kraton D1155 ES available from Kraton Corporation, Kurarity LA 4285, a PMMA-PnBA-PMMA triblock copolymer available from Kuraray Co., Ltd., Blendex 338 available from Galata Chemicals, and Nipol 1472 X available from Zeon Chemicals.

[0123] As described above, the composition may optionally include reinforcing rubber in the form of core-shell particles dispersed in the polymer matrix. The term "core-shell rubber" or CSR is used according to its standard meaning in the art to denote a rubber particle core formed of a polymer containing an elastic or rubbery polymer as a main component, and a shell layer formed of a polymer graft-polymerized on the core. The shell layer partially or completely covers the surface of the rubber particle core in the graft polymerization step. By weight, the core must constitute at least 50% by weight of the core-shell rubber particles.

[0124] The core polymer material has a glass transition temperature (Tg) of 0 °C or lower, preferably -20 °C or lower, more preferably -40 °C or lower, and even more preferably -60 °C or lower. The shell polymer is a non-elastic, thermoplastic or thermosetting polymer having a glass transition temperature (Tg) higher than room temperature, preferably higher than 30 °C, more preferably higher than 50 °C.

[0125] Without intending to limit the present invention, the core can be composed of a diene homopolymer, such as a homopolymer of 1,3-butadiene or 2-methyl-1,3-butadiene (isoprene); a diene copolymer, such as a copolymer of 1,3-butadiene or isoprene and one or more ethylenically unsaturated monomers, such as a vinyl aromatic monomer, (meth)acrylonitrile or (meth)acrylate; a polymer based on a (meth)acrylate monomer, such as polybutyl acrylate; and a polysiloxane elastomer, such as polydimethylsiloxane and crosslinked polydimethylsiloxane.

[0126] Similarly, without intending to limit the present invention, the shell can be composed of a polymer or copolymer of one or more monomers selected from (meth)acrylates, such as methyl methacrylate; vinyl aromatic monomers, such as styrene; vinyl cyanides, such as acrylonitrile; unsaturated acids and anhydrides, such as acrylic acid; and (meth)acrylamides. The polymer or copolymer used in the shell can have ionically crosslinked acid groups through the formation of metal carboxylates, particularly salts of divalent metal cations. The shell polymer or copolymer can also be covalently crosslinked by a monomer having two or more double bonds per molecule.

[0127] The core-shell rubber particles contained preferably have an average particle size (d50) of 10 nm to 300 nm, for example, 50 nm to 250 nm. The particle size refers to the diameter or the maximum dimension of the particles in the particle size distribution and is measured by dynamic light scattering. To be complete, this application does not exclude the presence of two or more core-shell rubber (CRS) particles having different particle size distributions in the composition in order to provide a balance of important properties of the resulting cured product, such as shear strength, peel strength, and resin fracture toughness.

[0128] The core-shell rubber can be selected from commercially available products, examples of which include Paraloid EXL2650A, EXL2655, and EXL2691A available from Dow Chemical Company; Clearstrength® XT100 available from Arkema; Kane Ace® MX series, particularly MX120, MX125, MX130, MX136, MX551, MX553 available from Kaneka Corporation; and METABLEN SX-006 available from Mitsubishi Rayon.

[0129] Rheology control agent The two-component (2K) composition of the present invention is characterized by the presence of a rheology control agent. Such an agent may be contained in either the first component (A) or the second component (B) of the composition, or both. When the rheology control agent is provided in both components of the composition, the nature of the agent in each part is determined independently and may be the same or different in each part. It is preferable that the first component (A) of the composition contains a rheology control agent.

[0130] The rheology control agent may consist of a non-conductive filler, a conductive filler, or a mixture thereof.

[0131] The presence of non-conductive fillers in the composition can help relax the viscosity of the composition and reduce the coefficient of thermal expansion of the adhesive. Generally, there is no special intention to limit the shape of the particles used as non-conductive fillers, and needle-shaped, spherical, elliptical, cylindrical, bead-shaped, cubic or platelet-shaped particles can be used alone or in combination. Furthermore, it is considered that aggregates of multiple types of particles can be used. Similarly, there is no special intention to limit the particle size used as the non-conductive filler. However, such non-conductive fillers conventionally have an average volume particle size of 0.01 to 1500 μm, for example 0.1 to 1000 μm or 0.1 to 500 μm, as measured by the laser diffraction / scattering method.

[0132] Exemplary non-conductive fillers include, but are not limited to, chalk, lime powder, precipitated silica, fumed silica, zeolite, bentonite, magnesium carbonate, diatomaceous earth, alumina, clay, talc, sand, quartz, flint, mica, glass powder, zinc oxide and other crushed mineral substances. Short fibers, such as glass fibers, glass filaments, polyacrylonitrile, carbon fibers, polyethylene fibers, etc. can also be added.

[0133] In the composition of the present invention, it is preferable to use precipitated silica and / or fumed silica as the rheology control agent. Such precipitated silica or fumed silica desirably has a BET surface area of 25 to 500 m 2 / g, for example 100 to 250 m 2 / g, as measured by the nitrogen adsorption method according to DIN 66131. A commercially available product of such fumed (pyrogenic) silica is Aerosil 200 available from Evonik Industries.

[0134] Suitable as the non-conductive filler are hollow spheres having a mineral shell or a plastic shell. These may be, for example, hollow glass spheres commercially available under the trade name Glass Bubbles (registered trademark). Plastic-based hollow spheres such as Expancel (registered trademark) and Dualite (registered trademark) may also be used, as described in European Patent No. 0520426. They are composed of inorganic or organic substances and have a diameter of 1 mm or less, preferably 500 μm or less, and preferably 100 μm to 200 μm, respectively.

[0135] Non-conductive fillers that impart thixotropic properties to the composition can be useful in certain applications. Such fillers are also called rheology aids and include, for example, hydrogenated castor oil, fatty acid amides, or swelling plastics such as PVC.

[0136] As described above, the composition of the present invention may further contain a conductive filler as at least a part of the rheology control agent. Generally, there is no intention to particularly limit the shape of the particles used as the conductive filler, and particles in the shape of needles, spheres, ellipses, cylinders, beads, cubes, or plates may be used alone or in combination. Furthermore, the use of aggregates of one or more particle types is also envisaged. Similarly, there is no intention to particularly limit the size of the particles used as the conductive filler. However, such conductive fillers usually have an average volume particle size measured by the laser diffraction / scattering method of 1 to 500 μm, for example, 1 to 200 μm.

[0137] Exemplary conductive fillers include silver, copper, gold, palladium, platinum, nickel, nickel coated with gold or silver, carbon black, carbon fiber, graphite, aluminum, indium tin oxide, copper coated with silver, aluminum coated with silver, glass spheres coated with metal, fillers coated with metal, polymers coated with metal, fibers coated with silver, spheres coated with silver, antimony-doped tin oxide, conductive nanospheres, nano silver, nano aluminum, nano copper, nano nickel, carbon nanotubes, carbon nanostructures, and mixtures thereof, but are not limited thereto. As the conductive filler, it is preferable to use particulate silver and / or carbon black and / or carbon nanostructures.

[0138] The total amount of the rheology control agent present in the composition of the present invention is preferably 1 to 20% by weight, more preferably 1 to 10% by weight based on the total weight of the composition. The desired viscosities of the components of the two-component (2K) composition and the desired viscosity of the curable composition formed by mixing the components usually determine the total amount of the rheology control agent added. Each component of the two-component composition desirably has a viscosity of 3000 to 150,000, for example 5000 to 100,000, and within such a viscosity range, each component should be easily extrudable from a suitable dispensing device such as a tube.

[0139] Oxygen scavenger The two-component (2K) composition of the present invention is characterized by the presence of at least one oxygen scavenger. The composition may contain 0.1 to 5% by weight of the oxygen scavenger based on the weight of the composition. The composition preferably contains 0.1 to 2% by weight, for example 0.1 to 1% by weight of the oxygen scavenger.

[0140] The oxygen scavenger may be included in either the first component (A) or the second component (B) of the composition, or in parts of both of them. When the oxygen scavenger is included in both components of the composition, the properties of the oxygen scavenger in each component are determined independently, and thus may be the same or different for each component. In the present specification, it is preferable that the first component of the composition contains an oxygen scavenger.

[0141] The oxygen scavenger should be reactive with active oxygen species and stable upon contact with oxygen or air at room temperature. Suitable examples of oxygen scavengers include the following: alkylated phenols; alkylated bisphenols; alkylidene bis, tris and polyphenols; thio, bis, tris and polyalkylated phenols; sulfur-containing esters; organic phosphines; organic phosphites; organic phosphates; hydroquinone; metals, especially inorganic compounds such as sulfates, sulfites, phosphites and nitrites of Group 1 and Group 2 and the first row transition metals of the periodic table, zinc and tin; sulfur-containing compounds such as thiodipropionic acid and its esters and salts, and thio-bis(ethylene glycol β-aminocrotonic acid); amino acids such as cysteine and methionine; and nitrogen-containing compounds capable of reacting with active oxygen including primary, secondary and tertiary amines. The oxygen scavenger is preferably selected from the group consisting of triphenylphosphine, triethyl phosphite, triisopropyl phosphite, triphenyl phosphite, tris(nonylphenyl) phosphite, butylated hydroxytoluene, butylated hydroxyanisole, tris(2,4-di-tert-butylphenyl) phosphite, dilauryl thiodipropionate, 2,2-methylenebis-(6-t-butyl-p-cresol), tetrakis(2,4-d-tert-butylphenyl) 4,4'-biphenylenediphosphonate, poly(4-vinylpyridine), and mixtures thereof.

[0142] It is noted that the oxygen scavenger can take the form of a polymer or an oligomer. Such forms can be prepared by covalently bonding a compound such as the listed oxygen scavenger to a monomer or comonomer. The limitation on the molecular size of the oxygen scavenger, if any, is determined by the effect it has on the functional properties of the other polymers it is combined with.

[0143] Additives and auxiliary components The composition obtained in the present invention usually further comprises adjuvants and additives that can impart improved properties to these compositions. For example, the adjuvants and additives can impart one or more of improved elastic properties, improved elastic recovery, longer processing time, faster curing time, and lower residual tack. Such adjuvants and additives can be included, independently of each other, in a single component or both components of a two-component (2K) composition, and include activators, plasticizers, stabilizers including UV stabilizers, reactive diluents, non-reactive diluents, desiccants, adhesion promoters, bactericides, flame retardants, dyes, and coloring pigments or coloring pastes.

[0144] Such adjuvants and additives can be used in the desired combinations and proportions as long as they do not adversely affect the nature and essential properties of the composition. Although there may be exceptions, these adjuvants and additives should not exceed 50% by weight of the entire composition in total, and preferably should not exceed 20% by weight of the composition.

[0145] To be complete, it is noted that auxiliary materials and additives containing reactive groups are generally blended into the appropriate components of a two-component (2K) composition to ensure their storage stability. Non-reactive materials can be incorporated into either or both of the two components.

[0146] The "plasticizer" in the present invention is a substance that reduces the viscosity of the composition and thereby improves its processability. Here, the plasticizer may account for up to 10% by weight or up to 5% by weight, based on the total weight of the composition, and preferably is selected from the group consisting of polydimethylsiloxane (PDMS), diurethane, ethers of monofunctional, linear or branched C4-C16 alcohols such as Cetiol OE (available from Cognis Deutschland GmbH, Dusseldorf), abietic acid, butyric acid, thiobutyric acid, acetic acid, esters of propionic acid and citric acid, esters based on nitrocellulose and polyvinyl acetate, fatty acid esters, dicarboxylic acid esters, esters of fatty acids having an OH group or epoxidized, glycolic acid esters, benzoic acid esters, phosphoric acid esters, sulfonic acid esters, trimellitic acid esters, epoxidized plasticizers, polyether plasticizers such as end-capped polyethylene or polypropylene glycol, polystyrene, hydrocarbon plasticizers, chlorinated paraffins, and mixtures thereof. In principle, phthalic acid esters can be used as plasticizers, but it should be noted that these are not preferred due to the potential toxicity. The plasticizer preferably contains or consists of one or more polydimethylsiloxanes (PDMS).

[0147] The "stabilizer" in the present invention is understood to be an antioxidant, a UV stabilizer, or a hydrolysis stabilizer. Here, the stabilizer may in total account for up to 10% by weight or up to 5% by weight, based on the total weight of the composition. Standard commercially available examples of stabilizers suitable for use here include sterically hindered phenols, thioethers, benzotriazoles, benzophenones, benzoates, cyanoacrylates, acrylates, hindered amine light stabilizer (HALS) type amines, phosphorus, sulfur, and mixtures thereof.

[0148] To further extend the shelf life, it is often recommended to further stabilize the composition of the present invention against moisture penetration using a desiccant. Also, there is sometimes a need to lower the viscosity of the adhesive composition of the present invention for specific applications by using a reactive diluent. The total amount of reactive diluent present is usually from 0 to 15 wt%, for example 0 to 5 wt%, based on the total weight of the composition.

[0149] In certain embodiments, it may be beneficial to include a dye within a two - component (2K) composition. Desirably, the added dye should be included in the first component of the composition. One of ordinary skill in the art would be able to select a suitable dye based on the desired color of the cured adhesive as well as its lightfastness, cost, toxicity profile, and solubility of the dye in the carrier medium. Generally, suitable dyes are selected from the classes of azo, anthraquinone, and triphenylmethane - type dyes, and the dyes can be chemically modified to enhance their solubility in the carrier medium or to reduce adsorption by the substrate surface onto which the adhesive is applied. Exemplary dyes that may be mentioned include PV Fast Blue BG and PV Fast Red B available from Clariant K.K.

[0150] The presence of solvents and non-reactive diluents in the composition of the present invention is also not excluded when their viscosities can be effectively suppressed thereby. For example, for illustrative purposes only, the composition may include one or more of the following: xylene; 2-methoxyethanol; dimethoxyethanol; 2-ethoxyethanol; 2-propoxyethanol; 2-isopropoxyethanol; 2-butoxyethanol; 2-phenoxyethanol; 2-benzyloxyethanol; benzyl alcohol; ethylene glycol; ethylene glycol dimethyl ether; ethylene glycol diethyl ether; ethylene glycol dibutyl ether; ethylene glycol diphenyl ether; diethylene glycol; diethylene glycol-monomethyl ether; diethylene glycol-monoethyl ether; diethylene glycol-mono-n-butyl ether; diethylene glycol dimethyl ether; diethylene glycol diethyl ether; diethylene glycol di-n-butyryl ether; propylene glycol butyl ether; propylene glycol phenyl ether; dipropylene glycol; dipropylene glycol monomethyl ether; dipropylene glycol dimethyl ether; dipropylene glycol di-n-butyl ether; N-methylpyrrolidone; diphenylmethane; diisopropylnaphthalene; petroleum fractions, such as Solvesso® products (available from Exxon); alkylphenols, such as tert-butylphenol, nonylphenol, dodecylphenol, and 8,11,14-pentadecatrienylphenol; styrenated phenol; bisphenol; aromatic hydrocarbon resins, especially those containing phenolic groups, such as ethoxylated or propoxylated phenol; adipate; sebacate; phthalate; benzoate; organic phosphates or sulfonic acid esters; and sulfonamides.

[0151] Separately from the above, the non-reactive diluent preferably constitutes less than 10% by weight, particularly less than 5% by weight or less than 2% by weight, in total, based on the total weight of the composition.

[0152] Exemplary embodiments of two-component (2K) compositions In an exemplary embodiment of the present invention, the two-component (2K) adhesive composition comprises Based on the weight of the first component, 30 to 60 wt%, preferably 35 to 50 wt% of a (meth)acrylate monomer, wherein the (meth)acrylate monomer comprises at least one C1-C6 alkyl ester of (meth)acrylic acid, 5 to 15 wt%, preferably 6 to 12 wt% of a copolymerizable acid, wherein the copolymerizable acid is selected from the group consisting of methacrylic acid, acrylic acid, itaconic acid, maleic acid, aconitic acid, crotonic acid, fumaric acid, and mixtures thereof, and 5 to 15 wt%, preferably 6 to 12 wt% of an electrolyte, wherein the electrolyte is selected from the group consisting of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, and mixtures thereof, a first component (A) comprising Based on the weight of the second component, a first curing agent comprising or consisting of 10 to 40 wt%, preferably 20 to 40 wt% or 30 to 55 wt%, preferably 30 to 45 wt% of at least one free radical initiator that decomposes under the action of heat to provide free radicals, a second curing agent consisting of at least one compound that is a salt or complex of a transition metal selected from the group consisting of Fe, Co, V, Mn, and Cu, 0.01 to 1 wt%, preferably 0.01 to 0.5 wt%, and 5 to 20 wt%, preferably 5 to 15 wt% of a wax, and 30 to 60 wt%, preferably 40 to 60 wt% of a solubilizer a second component (B) comprising and comprising wherein the first component (A) of the two-component (2K) adhesive composition further comprises, based on the total weight of the composition, 10 to 40 wt%, preferably 20 to 40 wt% of a reinforcing agent selected from the group consisting of non-reactive elastomers, core-shell rubber particles, and mixtures thereof, 0.1 to 2% by weight, preferably 0.1 to 1% by weight, of an oxygen scavenger, and 1 to 10% by weight of a rheology control agent comprising Furthermore, the first component (A) and the second component (B) are mixed at a weight ratio of A:B of 15:1 to 5:1, preferably 12:1 to 8:1, and most preferably 10:1.

[0153] In this embodiment, the first curing agent is preferably a peroxide or hydroperoxide compound selected from the group consisting of tert-butyl peroxide, tert-butyl perbenzoate, cumene hydroperoxide, tert-butyl peroxybenzoate, diacetyl peroxide, benzoyl peroxide, tert-butyl peracetate, lauryl peroxide and mixtures thereof. In particular, the selection of benzoyl peroxide is noted. Apart from or in addition to this mention of the selection of the first curing agent, the second curing agent preferably comprises or consists of at least one iron-based compound selected from the group consisting of ferrocene, iron(II) acetylacetonate and ammonium iron (3+) hexakis (cyano-C) ferrate(4-).

[0154] In this embodiment, it is more preferable that the reinforcing agent comprises or consists of at least one non-reactive elastomer.

[0155] Methods and Applications To form a defined two - component (2K) curable composition, the reactive components are brought together and mixed in such a way as to induce their curing. The reactive compounds need to be mixed under sufficient shear force to preferably produce a homogeneous mixture without the generation of foam during mixing. This is considered achievable without special conditions or special equipment. However, suitable mixing devices may include magnetic stir bar devices; wire whisks; augers; batch mixers; planetary mixers; C.W. Brabender or Banburry® type mixers; and high - shear mixers such as blade - type mixers and rotary impellers, etc.

[0156] For small - scale applications where a volume of usually less than 2 liters is used, a preferred packaging of the two - component (2K) composition is a side - by - side double - cartridge or co - axial cartridge where two tubular chambers (usually of equal volume) are arranged side - by - side or one inside the other and sealed with pistons. By driving these pistons, the components can be advantageously extruded from the cartridge using a closely attached static or dynamic mixer. For larger - scale applications, the two components of the composition can be advantageously stored in drums or pails. In this case, the two components are extruded using a hydraulic press, particularly via a follower plate, and supplied to a mixing device through a pipeline, thereby ensuring a fine and homogeneous mixing of the two components. In any case, for any package, it is important to seal - arrange the components with an airtight and moisture - proof seal so that both components can be stored for a long period, ideally for more than 12 months.

[0157] Non - limiting examples of two - component dispensing devices and methods suitable for the present invention include those described in U.S. Patent No. 6,129,244 and U.S. Patent No. 8,313,006.

[0158] Depending on the desired properties of the hardening composition, the two components are usually mixed at a weight ratio of component A: component B of 20:1 to 1:1, for example 15:1 to 5:1 or 12:1 to 8:1. A particularly preferred embodiment of the composition is a weight ratio of component A: component B of 10:1.

[0159] According to the broadest method aspect of the present invention, the above composition is applied to a material layer and then cured in place. Before applying the composition, it is often recommended to pretreat the relevant surface to remove foreign matter therefrom. This step, if applicable, facilitates the subsequent adhesion of the composition. Such treatments are known in the art and include, for example, etching treatment with an acid suitable for the substrate and, optionally, an oxidizing agent; ultrasonic treatment; plasma treatment such as chemical plasma treatment, corona treatment, atmospheric plasma treatment and flame plasma treatment; immersion in an aqueous alkaline degreasing bath; treatment with an aqueous cleaning emulsion; treatment with a cleaning solvent such as carbon tetrachloride or trichloroethylene; and one or more of rinsing with water, preferably deionized water or desalted water, in a one-step or multi-step method. When using an aqueous alkaline degreasing bath, it is desirable to remove the degreasing agent remaining on the surface by rinsing the substrate surface with deionized water or degreased water.

[0160] Next, the composition is preferably applied to the surface of the pretreated substrate by conventional coating methods such as brush coating; roll coating; doctor blade coating; printing methods; and spraying methods including, but not limited to, air spray, air-assisted spray, airless spray and high volume low pressure spray.

[0161] As described above, the present invention provides an adhesive structure including a first material layer having a conductive surface and a second material layer having a conductive surface, wherein a cured and peelable two-component (2K) adhesive composition defined in the foregoing and the appended claims is disposed between the first and second material layers. To manufacture such a structure, the adhesive composition is applied to the inner surface of at least one of the first material layer and / or the second material layer, and then the two layers are brought into contact such that the curable and peelable adhesive composition of the present invention is interposed between the two layers.

[0162] The composition is preferably applied to the surface with a wet film thickness of 10 to 500 μm. Applying to a thinner layer within this range is more economical and reduces the possibility of harmful thick cured regions. However, in order to avoid the formation of a discontinuous cured film, high-precision control must be performed when applying a thinner coating or layer.

[0163] Curing of the applied composition of the present invention typically occurs in the temperature range of 20°C to 200°C, preferably 25°C to 100°C, such as 25°C to 80°C or 25°C to 65°C. The appropriate temperature depends on the specific compounds present and the desired curing rate and can be determined in individual cases by those skilled in the art using simple preliminary tests as necessary. Naturally, curing at a lower temperature within the aforementioned range is advantageous because it does not require substantial heating or cooling of the mixture from the normal ambient temperature. However, where applicable, the temperature of the mixture formed from each component of the two-component (2K) composition can be raised to a temperature above the mixing temperature and / or the application temperature using conventional means such as microwave induction.

[0164] The present invention will be described with reference to the following accompanying drawings.

[0165] As shown in Figure 1a attached to this specification, an adhesive structure is provided in which a layer of a curable adhesive (10) is disposed between two conductive substrates (11). A layer of a non-conductive material (12) can be disposed on the conductive substrate (11) to form a more complex adhesive structure as shown in Figure 1b. Each layer of the conductive substrate (11) is in electrical contact with a power source (13) which can be a battery or an AC-driven direct current (DC) source. The positive and negative terminals of the power source (13) are shown in one fixed position, but of course those skilled in the art will recognize that the polarity of the system can be reversed.

[0166] The two conductive substrates (11) are shown in the form of layers that can be constituted by, among other things, a metal film; a metal sheet; a metal mesh or grid; deposited metal particles; a resin material made conductive by conductive elements disposed therein; or a conductive oxide layer. Exemplary conductive elements can include silver filaments, single-walled carbon nanotubes, and multi-walled carbon nanotubes. Exemplary conductive oxides can include doped indium oxide, such as indium tin oxide (ITO); doped zinc oxide; antimony tin oxide; cadmium stannate; and zinc stannate. Apart from the selection of the conductive material, those skilled in the art will recognize that if the conductive substrate (11) is in the form of a grid or mesh that limits contact with the layer of the curable adhesive (10), the effectiveness of the peeling operation can be reduced.

[0167] When a voltage is applied between each conductive substrate (11), a current is supplied to the adhesive composition (10) disposed therebetween. This induces an electrochemical reaction at the interface between the substrate (11) and the adhesive composition. This electrochemical reaction is understood to be oxidative at the positively charged or anodic interface and reductive at the negatively charged or cathodic interface. The reaction is thought to weaken the adhesive bond between the substrates and allow the composition that can be peeled from the substrates to be easily removed.

[0168] As depicted in FIGS. 2a and 2b, delamination occurs at the positive interface, which is the interface between the adhesive composition (10) and the conductive surface (11) in electrical contact with the positive electrode. By reversing the direction of the current before separating the substrates, the adhesive bond can be weakened at both substrate interfaces.

[0169] However, it should be noted that the composition of the adhesive layer (10) can be adjusted so that delamination occurs at either the positive or negative interface, or simultaneously from both. For some embodiments, the voltage applied to both surfaces to form the anode and cathode interfaces causes delamination to occur simultaneously at both the anode and cathode adhesive / substrate interfaces. In another embodiment, if the composition does not respond to direct current at both interfaces, reverse polarity can be used to delaminate both substrate / adhesive interfaces simultaneously. The current can be applied in any suitable waveform, provided that the total time allowed for delamination to occur at each polarity is sufficient. Sinusoidal, rectangular, and triangular waveforms may be appropriate in this regard and can be applied from a controlled voltage or current source.

[0170] Without intending to limit the present invention, it is believed that the delamination operation can be effectively performed when at least one, preferably both, of the following conditions are caused: a) an applied voltage of 0.5 to 100 V; and, b) a voltage applied for a period of 1 second to 60 minutes. If the delamination of the conductive substrate from the cured adhesive is facilitated by the application of a force exerted, for example, by a weight or a spring, the potential only requires an application on the order of a few seconds. In some embodiments, a potential of 5 V for 10 minutes is sufficient to have a delamination effect.

[0171] After delamination, it is desirable that the adhesive composition be present only on the first or second substrate, which means that one of the substrates is substantially free of the adhesive.

[0172] The following examples are illustrative of the present invention and are not intended to limit the scope of the present invention in any way.

Example

[0173] Examples In the examples, the following materials were used: 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide: Available from Sigma Aldrich 1-Dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide: Available from Sigma Aldrich Trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide: Available from Sigma Aldrich Cyphos IL 109: Available from Solvay Methyl methacrylate: Available from Sigma Aldrich Methacrylic acid: Available from Acros Organics 2-Hydroxyethyl methacrylate phosphate ester: Available from Sigma Aldrich 2,2’-(4-Methylphenylimino)diethanol: Available from Sigma Aldrich Garamite 1958: A powder rheology additive based on organophilic phyllosilicate, available from BYK Aerosil 200: Hydrophilic fumed silica, available from Evonik Industries Zinc oxide nanopowder: Available from Sigma Aldrich Kraton D 1155 ES: A linear block copolymer based on styrene and butadiene with a mass of bound styrene of 40%, available from Kraton Corporation Kurarity LA 4285: An all-acrylic block copolymer (MAM), available from Kuraray Co., Ltd. Nipol 1472 X: Acrylonitrile-butadiene rubber, available from Zeon Chemicals Hypro 2000X168 LC VTB: Methacrylate-terminated polybutadiene rubber, available from Huntsman Blendex 338: Ultra-high rubbery acrylonitrile butadiene rubber (ABS) resin, available from Galata Chemicals Pluracol V10: Ethylene oxide-propylene oxide copolymer ether with trimethylolpropane (CAS No. 52624-57-4), available from BASF SE Benzoflex 2088: Blend of diethylene glycol benzoate, dipropylene glycol benzoate and triethylene glycol benzoate, available from Eastman Chemical Company Triphenylphosphine: Available from Merck KGaA Wax component: Paraffin wax, available from International Group Inc Ferrocene: Available from Merck DER 331: Bisphenol A epoxy resin, available from Olin Corporation Benzoyl peroxide (75%): Powder, available from Arkema Inc.

[0174] The following test methods were used for the property evaluation of the two-component preparation: Tensile Lap Shear (TLS) Test: The substrates tested were nickel (thickness 1.5 mm), aluminum (AA6016, thickness 1.25 mm) and stainless steel (1.4301, thickness 1.5 mm). The substrates were cut to a size of 2.5 cm × 10 cm for tensile testing. The tensile lap shear (TLS) test was carried out at room temperature based on EN 1465:2009 (German version) Adhesives - Determination of Tensile Lap - shear Strength of Bonded Assemblies. The adhesive overlap area for each described substrate was 2.5 cm × 1.0 cm (1” × 1”) and the adhesive thickness was 150 microns. The applied two - component (2K) adhesive composition was cured at 80 °C for 30 minutes in the overlap area. The test specimens were placed in the grips of a universal testing machine and pulled at a speed of 10 mm per minute until failure occurred. The grips fixing the ends of the assembly need to be aligned so that the applied force passes through the center line of the test specimen. The type of failure is either an adhesive failure where the adhesive separates from one of the substrates or a cohesive failure where the adhesive ruptures internally.

[0175] Test over Time: The substrates tested were aluminum (AA6016, thickness 1.25 mm) and stainless steel (1.4301, thickness 1.5 mm). The substrates were cut to a size of 2.5 cm × 10 cm for tensile testing. The adhesive overlap area for each substrate was 2.5 cm × 1.0 cm and the adhesive thickness was 150 microns. The applied two - component (2K) adhesive composition was cured at 45 °C (Example 1) or 80 °C (Example 2) for 20 minutes in the overlap area. The test specimens were stored in an artificial climate chamber with a relative humidity of 90% and a temperature of 65 °C. At specific time points during storage (1 day, 7 days, 14 days, 21 days), a tensile lap shear (TLS) test was carried out at room temperature based on the above - mentioned method (EN 1465:2009, German version). The test specimens were placed in the grips of a universal testing machine and pulled at 10 mm / min until failure occurred.

[0176] Thin Bond Line Test: The substrate tested was stainless steel (1.4301, thickness 1.5 mm). The substrate was cut into a size of 2.5 cm × 10 cm for tensile testing. The adhesive overlap area of each substrate was 2.5 cm × 0.25 cm, and the adhesive thickness was 150 microns. The two-component (2K) adhesive composition applied was cured at 80 °C for 20 minutes in the overlap area. The tensile lap shear (TLS) test was carried out at room temperature based on the above method (EN1465:2009, German version). The test specimens were placed in the grips of a universal testing machine and pulled at a rate of 10 mm / min until failure occurred.

[0177] T-Peel Resistance (N / mm): The test for this parameter is based on the following standards: ASTM D1876 Peel Resistance of Adhesives; ISO 11339 Adhesives 180° Peel Test for Flexible-to-Flexible Bonded Assemblies; DIN 53282 Testing of Adhesives for Metals and Adhesively Bonded Metal Joints. For each test point, at least three test specimens were assembled and tested. The adhesion was prepared using an aluminum peel substrate wiped with acetyl acetate to remove dirt and grease. The composition to be evaluated was applied to both sides of the peel strip test specimens. Starting from one end, a spreading stick was used to spread the composition to ensure coverage of a 25 × 50 mm area. Next, the second peel strip test specimen was combined with the coated peel strip test specimen. The resulting assembly was clamped with a total of three clamps, one clamp on each side of the assembly and one clamp at the end of the assembly, so that the clamping load was evenly distributed. Next, the composition was cured in the assembly at 80 °C for 20 minutes. After 24 hours, the clamps were removed and the adhesion part was pulled to calculate the T-peel results.

[0178] Impact resistance (N / mm): The test for this parameter is based on the following standard: ASTM 3762 Standard Test Method for Adhesive-Bonded Surface Durability of Aluminum (Wedge Test). In this test, aluminum test specimens were prepared according to ASTM D1002. According to these standards, a pendulum impact tester was used. This tester is equipped with a retaining bolt, an active strain gauge and a hammer fin, and further equipped with instruments for measuring force-time curves and force-deflection curves. For each test specimen, the applied two-component (2K) adhesive composition was cured at 80 °C for 20 minutes in the overlap area. The test specimen was inserted into the wedge test fixture with the non-bonded end protruding just enough to wedge between the adherends. Next, the test fixture was assembled onto the test specimen retaining bolt, first tightened by hand and then further tightened by 1 / 4 turn using a suitable tool. Next, after stabilizing the test specimen at 25 °C and 50% relative humidity, an impact was applied with the impact speed specified at 2.3 m / s -1 The transducer signal was automatically and non-selectively detected and recorded by the microprocessor during the impact event. Thereafter, the force-time (or force-displacement) data were individually manipulated.

[0179] Film properties: The elastic modulus (MPa), elongation at break and tensile strength (MPA) of the adhesive film were tested according to ASTM D638 - 14 Standard Test Method for Tensile Properties of Plastics. An adhesive film with a thickness of 2.3 mm was prepared by curing the two-component (2K) adhesive composition at 80 °C for 20 minutes.

[0180] Viscosity: The measurement of the exemplified compositions was carried out at a shear rate of 20 s -1 The components (B) of the two-component compositions of Compositions 1 to 6 were prepared according to Table 1 below.

[0181]

[0182] ​

Table 1

[0183] Example 1 Component (A) of Composition 1 of Example 1 was prepared according to Table 2 below.

[0184]

Table 2

[0185] The components were filled into separate compartments of a 50 g cartridge at a weight ratio (A:B) of 10:1, and both ends were sealed. Next, the cartridge was loaded into a cartridge gun, and a mixing tip was attached to the front end. By applying a constant pressure to the trigger, the two components were pushed into the mixing tip, thoroughly mixed, and then applied to a specified substrate.

[0186] For each substrate, tests of tensile lap shear strength, over time, peel strength, wedge impact, and film properties were carried out as described above. The applied two-component (2K) adhesive composition was cured in the overlap region by applying the temperature conditions described in each test. When applicable, the samples were stored in an artificial climate chamber before the test.

[0187] The results are listed in Table 3 below.

[0188]

Table 3

[0189] For the adhesively bonded stainless steel substrate, the lap shear strength (MPa) under the peeling conditions shown in Table 4 below, specifically when a potential was applied across the entire bonding area and when no potential was applied, was investigated. When applicable, the aged test specimens were stored in an artificial climate chamber at 90% relative humidity and 65 °C, and a constant potential (30 V) was applied across the entire overlap bonding area for 20 minutes.

[0190]

Table 4

[0191] Example 2 Component (A) of the composition of Example 2 was prepared according to Table 5 below.

[0192]

Table 5

[0193] The components were loaded into separate compartments of a 50 g cartridge at a weight ratio (A:B) of 10:1, and both ends were sealed. The cartridge was loaded into a cartridge gun, and a mixing tip was attached to the front end. By applying a constant pressure to the trigger, the two components were pushed into the mixing tip, thoroughly mixed, and then applied to the specified substrate.

[0194] For each substrate, tensile lap shear strength, over time, peel resistance, wedge impact, and film property tests were performed in the same manner as above. The applied two-component (2K) adhesive composition was cured in the overlap area by applying the temperature conditions described in each test. When applicable, the samples were stored in an artificial climate chamber before the test.

[0195] The test results of Composition 2 are shown in Table 6 below.

[0196]

Table 6

[0197] The test results of Composition 3 are shown in Table 7 below.

[0198]

Table 7

[0199] The test results of Composition 4 are shown in Table 8 below.

[0200]

Table 8

[0201] The test results of Composition 5 are shown in Table 9 below.

[0202]

Table 9

[0203] The test results of Composition 6 are shown in Table 10 below.

[0204]

Table 10

[0205] Example 3 The compositions 7, 9, and 9 of Example 4 were prepared according to Table 11 below.

[0206]

Table 11

[0207] The individual component A of the adhesive was prepared by adding all the raw materials to a single pot and stirring overnight to dissolve all the raw materials. The final adhesive was obtained by adding the individual components A and B at a ratio of 10:1 respectively and speed mixing at 3000 rpm for 15 seconds.

[0208] The coating substrate of the composition was stainless steel (EN 1.4301), cut into pieces of 2.5 cm × 10 cm in size, and had a thickness of 1.50 mm. In order to control the thickness of the coating composition applied between both substrates, glass beads with a diameter of 100 - 200 microns were used as spacers. Based on EN 1465:2009 (German version) Based on Adhesives - Determination of tensile Lap Shear strength of bonded assemblies, a tensile lap shear (TLS) test was carried out at room temperature.

[0209] The adhesive overlap area of each substrate was 2.5 cm × 1.0 cm, and the adhesive thickness was 0.1 cm (40 mil). The applied adhesive composition was first left to stand under ambient conditions for 1 hour and then cured in the overlap area by keeping it at a temperature of 80 °C for 30 minutes. Next, the joined structure was stored at room temperature for 24 hours and then the first tensile test was carried out, or it was stored in an artificial climate chamber at 65 °C and a relative humidity of 90% to conduct an accelerated aging test.

[0210] After the 24-hour storage period, the values of the tensile lap shear strength after storage in an artificial climate chamber at 65 °C and a relative humidity of 90% were collected both before and after applying a constant potential of 50 V across the adhesive layer for 30 minutes. The results are shown in Table 12 below.

[0211]

Table 12

[0212] Table 12 summarizes the results obtained for different ionic liquids (BMIM NTf2, DDMIM NTf2, and Cyphos IL 109). Compositions 7 - 9 all show good stability after storage at 65 °C and a relative humidity of 90% for 3 weeks, with Composition 9 using Cyphos IL 109 being the most excellent. The electrochemical delamination performance varies. DDMIM NTf2 of Composition 9 showed the best overall delamination performance. BMIM NTf2 had a poor initial delamination process but still showed a reduction of more than 50% compared to the same system using MMA as the acrylic monomer. When stored under conditions of 65 °C and a relative humidity of 90%, surprisingly, the delamination deteriorated after 1 week but improved dramatically after 3 weeks. On the other hand, Cyphos IL 109 showed very good initial interlayer delamination but exhibited the opposite behavior of deteriorating when stored at 65 °C and a relative humidity of 90% for 3 weeks.

[0213] Example 4 Compositions 10 - 13 of Example 5 were prepared according to Table 13 below. R1 is the reference composition.

[0214]

Table 13

[0215] Starting from the good performance of Composition 9 of Example 4, the composition was reproduced by varying the amount of the ionic liquid Cyphos IL 109 (0, 4.26, 6.25, 8.16 and 10 wt%). The individual component A of the adhesive was prepared by first adding all the raw materials into one pot and stirring overnight to dissolve all the raw materials. The final adhesive was obtained by adding the individual components A and B at a ratio of 10:1 respectively and speed mixing at 3000 rpm for 15 seconds.

[0216] The coating substrate of the preparation was stainless steel (EN 1.4301), cut into a size of 2.5 cm × 10 cm, and had a thickness of 1.50 mm. Glass beads with a diameter of 100 - 200 microns were used as spacers to control the thickness of the coating composition applied between the two substrates. Based on EN 1465:2009 (German version) Based on Adhesives - Determination of tensile Lap Shear strength of bonded assemblies, a tensile lap shear (TLS) test was carried out at room temperature.

[0217] The bonded overlap area of each substrate was 2.5 cm × 1.0 cm, and the adhesive thickness was 0.1 cm (40 mil). The applied adhesive composition was first left at ambient conditions for 1 hour and then cured in the overlap area by keeping it at a temperature of 80 °C for 30 minutes. Then, the bonded structure was stored at room temperature for 24 hours and then the first tensile test was carried out, or it was stored in an artificial climate chamber at 65 °C and a relative humidity of 90% to carry out an accelerated aging test.

[0218] After the 24 - hour storage period, the values of the tensile lap shear strength after storage in an artificial climate chamber at 65 °C and a relative humidity of 90% were collected both before and after applying a constant potential of 50 V across the adhesive layer for 30 minutes. The results are described in Table 14 below.

[0219]

Table 14

[0220] The reference composition R1 showed a strong increase in the lap shear strength value after being stored at 65°C and 90% relative humidity for 1 week. However, overall, after being stored at 65°C and 90% relative humidity for 3 weeks, only a slight increase was observed from the initial lap shear strength.

[0221] As the content of Cyphos IL 109 increased, the lap shear strength at the start was observed to gradually decrease from 20 MPa or more (Composition 10) to 15 MPa (Composition 13). Also, in all compositions, an increase in the lap shear strength was observed after being stored at 65°C and 90% relative humidity for 1 week, but as the content of Cyphos IL 109 increased, the increase became smaller. Finally, after being stored at 65°C and 90% relative humidity for 3 weeks, a decrease in the lap shear strength was seen in all compositions. Overall, the decrease in the lap shear strength after being stored at 65°C and 90% relative humidity for 3 weeks was small compared to the initial value, meaning that all compositions were very stable after being stored at 65°C and 90% relative humidity. Finally, the electrochemical delamination performance was worst in Composition 10 with 4.26 wt% of Cyphos IL 109 added. Nevertheless, the decrease in the lap shear strength was still more than 50%, which was much better compared to the system using MMA as the acrylic monomer. When the content of Cyphos IL 109 was higher than 4.26 wt%, excellent delamination performance was shown, but when stored at 65°C and 90% relative humidity, a decrease in performance was observed, and the final delamination performance still maintained more than 50%, which was much superior compared to the system using MMA as the acrylic monomer.

[0222] Considering the foregoing description and examples, it will be apparent to those skilled in the art that equivalent changes can be made without departing from the scope of the appended claims.

Claims

1. (Meth)acrylate monomer, Copolymerizable acids, and electrolyte The first component (A) includes, The first curing agent of the monomer of the first component, A second curing agent for the monomer of the first component, wax, and Solubilizer, The second component (B) includes and A curable and peelable two-component adhesive composition comprising: Here, the two-component adhesive composition further, Reinforcement agent; Oxygen scavengers; and Rheology control agents; Includes, Furthermore, the two-component adhesive composition contains an electrolyte of formula (I) or formula (II): [wherein, R １ , R ２ , R ３ , R ４ and R ５ are each independently selected from hydrogen, C １ -C １８ alkyl, C ３ -C １８ cycloalkyl, C ６ -C １８ aryl, C ７ -C ２４ aralkyl, C ２ -C ２０ alkenyl, -C(O)R ｑ , -C(O)OH, -CN or -NO ２ and R ｑ is C １ -C ６ alkyl, and X- is It is a pair anion selected from the group consisting of (wherein R, ａ and R ｂ is hydrogen, C １ -C １２ Alkyl, C ５ -C １２ Cycloalkyl, C ５ -C １２ Heterocycloalkyl, C ６ -C １８ Aryl or C ５ -C １８ (Selected independently of heteroaryls) A curable and peelable two-component adhesive composition characterized by containing or comprising at least one salt described in [the relevant text].

2. The (meth)acrylate monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl-(meth)acrylate, and nonyl (meth)acrylate. Decyl (meth)acrylate, dodecyl (meth)acrylate, phenyl (meth)acrylate, tolyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, stearyl (meth)acrylate, glycidyl (meth)acrylate, isobornyl (meth)acrylate, 2-aminoethyl (meth)acrylate, γ-(meth)acryloyloxypropyl trimethoxyacrylate Sisilane, (meth)acrylic acid-ethylene oxide adduct, trifluoromethylmethyl (meth)acrylate, 2-trifluoromethylethyl (meth)acrylate, 2-perfluoroethylethyl (meth)acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate, 2-perfluoroethyl (meth)acrylate, perfluoromethyl (meth)acrylate, diperfluoromethylmethyl (meth)acrylate, 2-perfluoromethyl-2-perfluoroethylmethyl (meth)acrylate, 2-perfluorohex Silethyl (meth)acrylate, 2-perfluorodecylethyl (meth)acrylate, 2-perfluorohexadecylethyl (meth)acrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, dipentaerythritol monohydroxypentaacrylate, pentaerythritol triacrylate, ethoxylated trimethylolpropane triacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, pentaerythritol tetraacrylate, 1,2-Butylene glycol diacrylate, trimethylolpropane ethoxylate tri(meth)acrylate, glyceryl propoxylate tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, tripropylene glycol di(meth)acrylate, neopentyl glycol propoxylate di(meth)acrylate, 1,4-butanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, A curable and peelable two-component adhesive composition according to claim 1, wherein the (meth)acrylate monomer is selected from the group consisting of ethylene glycol di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate and mixtures thereof, preferably, the (meth)acrylate monomer is selected from the group consisting of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, isobornyl methacrylate, isobornyl acrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane triacrylate and mixtures thereof.

3. The curable and peelable two-component adhesive composition according to claim 1, wherein the (meth)acrylate monomer component is present in an amount of 20 to 80% by weight, preferably 30 to 60% by weight, and more preferably 35 to 50% by weight of the total weight of the first component.

4. The curable and peelable two-component adhesive composition according to claim 1, wherein the copolymerizable acid is selected from the group consisting of methacrylic acid, acrylic acid, itaconic acid, maleic acid, aconitic acid, crotonic acid, fumaric acid, and mixtures thereof, preferably the copolymerizable acid is methacrylic acid.

5. The curable and peelable two-component adhesive composition according to claim 1, wherein the copolymerizable acid is present in an amount of 0.5 to 20% by weight, preferably 5 to 15% by weight, and more preferably 6 to 12% by weight, of the total weight of the first component.

6. The electrolytes are: 1-methylimidazolium bis(trifluoromethylsulfonyl)imide; 3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-propyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide; 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide; 1-decyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide A curable and peelable two-component adhesive composition according to claim 1, preferably selected from the group consisting of butylsulfonyl)imide, 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, tetraethylphosphonium bis(trifluoromethylsulfonyl)imide, tetrabutylphosphonium bis(trifluoromethylsulfonyl)imide, tridecyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide and mixtures thereof.

7. The curable and peelable two-component adhesive composition according to claim 1, wherein the electrolyte is present in an amount of 0.5 to 20% by weight, preferably 5 to 15% by weight, and more preferably 6 to 12% by weight, of the total weight of the first component.

8. The first curing agent is a peroxide curing agent, The curable and peelable two-component adhesive composition according to claim 1, wherein the peroxide curing agent is preferably selected from the group consisting of tert-butyl peroxide, tert-butyl perbenzoate, cumene hydroperoxide, tert-butyl peroxybenzoate, diacetyl peroxide, benzoyl peroxide, tert-butyl peracetate, lauryl peroxide, and mixtures thereof, and more preferably the peroxide curing agent is benzoyl peroxide.

9. The curable and peelable two-component adhesive composition according to claim 1, wherein the first curing agent is present in an amount of 5 to 40% by weight of the total weight of the second component.

10. The curable and peelable two-component adhesive composition according to claim 1, wherein the second curing agent is a metal compound selected from salts and complexes of iron, copper, cobalt, vanadium, and manganese, and the second curing agent is preferably an iron-based compound selected from the group consisting of ferrocene, iron(II) acetylacetonate, ammonium iron ferrocyanide, and mixtures thereof.

11. The curable and peelable two-component adhesive composition according to claim 1, wherein the second curing agent is present in an amount of 0.01 to 2% by weight, preferably 0.01 to 1% by weight, and more preferably 0.01 to 0.5% by weight, of the total weight of the second component.

12. The curable and peelable two-component adhesive composition according to claim 1, wherein the solubilizer is polyethylene glycol, or an epoxy resin selected from the group consisting of alicyclic epoxides, epoxy novolac resins, bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol A epichlorohydrin epoxy resins, alkyl epoxides, limonene dioxides, polyepoxides, and mixtures thereof, preferably the solubilizer is a bisphenol A epoxy resin.

13. The curable and peelable two-component adhesive composition according to claim 1, wherein the solubilizer is present in an amount of 20 to 60% by weight, preferably 30 to 60% by weight, and more preferably 40 to 60% by weight, of the total weight of the second component.

14. The curable and peelable two-component adhesive composition according to claim 1, wherein the reinforcing agent is present in an amount of 5 to 40% by weight, preferably 10 to 40% by weight, and more preferably 20 to 40% by weight, of the total weight of the composition.

15. The curable and peelable two-component adhesive composition according to claim 1, wherein the first component (A) and the second component (B) are blended in a weight ratio A:B of 20:1 to 1:1, preferably 15:1 to 5:1, and more preferably 12:1 to 8:

1.

16. A first material layer having a conductive surface, and Second material layer having a conductive surface An adhesive structure including, An adhesive structure in which a cured, peelable two-component adhesive composition according to any one of claims 1 to 15 is disposed between the first material layer and the second material layer.

17. i) A step of applying a voltage to both surfaces to form an anode interface and a cathode interface, and ii) Step of peeling off both surfaces A method for peeling off the adhesive structure according to claim 16, including the following:

18. The method according to claim 17, wherein the voltage applied in step i) is 0.5 to 100V, and the voltage is preferably applied for a period of 1 second to 60 minutes.

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