One-component (1K) curable adhesive composition

Abstract

The present invention relates to an epoxy resin, a curing agent for the epoxy resin, an electrolyte, and d) a non-conductive filler; and at least one of e) a combination of a solubilizer and a toughening agent; and f) conductive particles.

Description

Technical Field

[0001] The present invention relates to an adhesive composition that can be peeled off from a specific coated substrate. More specifically, the present invention relates to a curable, one-component (1K) peelable adhesive composition.

Background Art

[0002] 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 shields the joint from corrosive species.

[0003] Accordingly, 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 located between the substrates and cannot be accessed without damaging the surface of the substrates 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) and U.S. Patent No. 4,729,797 (Linde et al.), may be effective but can be time-consuming and complex to implement. Furthermore, the required aggressive chemicals or harsh conditions can damage the separated substrates and render them unsuitable for subsequent applications.

[0004] Taking these problems into consideration, certain authors have attempted to develop a peelable adhesive composition in which a cured composition acts to break the adhesion at the interface between the adhesive and the substrate by passing an electric current.

[0005] U.S. Patent No. 7,465,492 (Gilbert) describes an electrically releasable composition that includes a matrix functionality, a free radical initiator, and an electrolyte, the monomer being selected from the group consisting of acrylic, methacrylic, and combinations thereof, the electrolyte providing 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 peeled from the surface.

[0006] U.S. Patent Application Publication No. 2007 / 0269659 (Gilbert) describes an adhesive composition that is releasable at two interfaces, the composition including (i) a polymer and an electrolyte, (ii) facilitating the bonding of two surfaces, and (iii) peeling 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.

[0007] U.S. Patent Application Publication No. 2008 / 0196828 (Gilbert) describes a hot melt adhesive composition that includes a thermoplastic component and an electrolyte, the electrolyte providing the composition with sufficient ionic conductivity 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.

[0008] 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 said 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 adhesive substrate; e) applying a voltage to the adhesive substrate, thereby substantially weakening the adhesion at at least one interface between the electrically peelable hot melt adhesive composition and the substrate surface.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0010] There remains a technical need to provide an adhesive composition that can be easily applied to the surface of a substrate to be joined and, upon curing, provide an effective bond within the composite structure including the substrate, but can be effectively peeled from those substrates by simply applying a potential across the entire cured adhesive.

Means for Solving the Problems

[0011] According to a first aspect of the present invention, a) an epoxy resin; b) a curing agent for the epoxy resin; c) an electrolyte; and, d) a non-conductive filler; comprising, e) a combination of a solubilizer and a strengthening agent, and, f) conductive particles there is provided a curable and peelable one-component (1K) adhesive composition containing at least one of.

[0012] In an important embodiment of the present invention, the peelable one-component (1K) adhesive composition is, based on the total weight of the composition, 15 to 75% by weight, preferably 20 to 65% by weight, of the epoxy resin a), 0.01 to 25% by weight, preferably 0.1 to 23% by weight, of the curing agent b) for the epoxy resin, 2.0 to 25% by weight, preferably 3 to 20% by weight, of the electrolyte c), and, 1 to 50% by weight, preferably 1.5 to 48% by weight, of the non-conductive filler d), comprising, when the adhesive composition contains the combination of the solubilizer and the strengthening agent, the composition contains 1 to 15% by weight, preferably 2 to 10% by weight, of the solubilizer, 5 to 40% by weight, preferably 10 to 25% by weight, of the strengthening agent, comprising, furthermore, when the adhesive composition contains the conductive particles, the composition contains 0.1 to 5% by weight, preferably 0.5 to 4% by weight, of the conductive particles f).

[0013] In some embodiments, the curing agent comprises, or consists of, tris-(3-mercaptopropionate) (TMP), pentaerythritol tetra(3-mercaptopropionate), di-pentaerythritol hexa(3-mercaptopropionate), pentaerythritol tetra(3-mercaptopropionate), tris(2-(mercaptopropionyloxy)ethyl) isocyanate, and mixtures thereof. In this regard, the use of tris-(3-mercaptopropionate) may be preferred.

[0014] Alternatively, the curing agent may comprise, or consist of, an amine-based curing agent, preferably an amine-based curing agent selected from the group consisting of alicyclic amines, aliphatic amines, dicyandiamide, polyetheramines, and mixtures thereof. In this regard, the use of polyetheramines, dicyandiamide, and mixtures thereof may be preferred.

[0015] 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 comprising a curable and peelable one-component (1K) adhesive composition as defined in the above and the appended claims is provided between the first material layer and the second material layer.

[0016] According to a third aspect of the present invention, i) applying a voltage across the entire surface to form an anode interface and a cathode interface, and ii) peeling the two surfaces as described above A method of peeling the adhesive structure as defined in the above and the appended claims is provided.

[0017] Step i) of this method preferably a) an applied voltage of 0.5 to 200 V, and b) a voltage applied for 1 second to 120 minutes, preferably 1 second to 60 minutes characterized by at least one of the following.

Brief Description of the Drawings

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Modes for Carrying Out the Invention

[0019] <Definitions> As used herein, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

[0020] As used herein, the terms "comprising" and "comprised of" are synonymous with "including", "includes", "containing", or "contains", and are inclusive or open-ended and do not exclude additional, unrecited members, elements, or method steps.

[0021] As used herein, the term "consisting of" excludes elements, components, members, or method steps not specified.

[0022] When expressing a quantity, concentration, dimension, or other parameter in the form of a range, preferred range, upper limit value, lower limit value, or preferred upper limit value and limit value, any range obtained by combining any upper limit or preferred value with any lower limit or preferred value should be understood to be specifically disclosed, regardless of whether the resulting range is clearly recited in the context.

[0023] 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 %.

[0024] 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.

[0025] 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.

[0026] As used herein, room temperature is 23°C plus or minus 2°C. As used herein, "ambient conditions" means the temperature and pressure of the surroundings in which the composition is placed, or in which the coating layer or the substrate of the coating layer is placed.

[0027] As used herein, the term "peelable" means that after curing of the adhesive, applying a potential of 10 V to 75 V for 20 minutes ~60 minutes can reduce the adhesive strength by at least 50%. The cured adhesive is applied between two substrates adhered by the adhesive such that current flows through the adhesive bond line. The adhesive strength is measured by a tensile lap shear (TLS) test based on EN 1465:2009 (German version) Adhesives - Determination of tensile lap shear strength of bonded assemblies, performed at room temperature. The overlap area of the bond was 25 mm × 10 mm and had an adhesive thickness of approximately 150 μm.

[0028] 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.

[0029] 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.

[0030] As used herein, the term "electrolyte" is used in accordance with its standard meaning in the art as a substance that contains free ions capable of conducting electricity by the movement of charged carrier species. 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.

[0031] The curable adhesive composition of the present invention and the cured adhesive obtained therefrom 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.

[0032] As used herein, "(meth)acrylic" is a shortened form that refers to "acrylic" and / or "methacrylic". Thus, the term "(meth)acrylamide" refers collectively to acrylamide and methacrylamide.

[0033] 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 alkanes and includes straight-chain and branched-chain organic groups. Thus, "C1-C 30The term "alkyl" refers to a monovalent group containing 1 to 30 carbon atoms, which is a group of alkanes and includes linear and branched organic groups. 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 substituents such as halo, nitro, cyano, amide, amino, sulfonyl, sulfinyl, sulfanyl, sulfoxy, urea, thiourea, sulfamoyl, sulfamide, and hydroxy. When applicable, the selection of a given substituent is noted in the specification. However, generally, an alkyl group containing 1 to 18 carbon atoms (C1-C 18 alkyl), for example, an alkyl group containing 1 to 12 carbon atoms (C1-C 12 alkyl) or an alkyl group containing 1 to 6 carbon atoms (C1-C6 alkyl) is noted.

[0034] As used herein, the term "C1-C 18 hydroxyalkyl" refers to an HO-(alkyl) group having 1 to 18 carbon atoms, where the point of attachment of the substituent is via an oxygen atom and the alkyl group is as defined above.

[0035] "Alkoxy group" refers to a monovalent group represented by -OA (where A is an alkyl group), and non-limiting examples thereof are methoxy group, ethoxy group, and 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 1 to 18 carbon atoms in the (alkyl-O-alkyl) moiety. Such groups include methoxymethyl (-CH2OCH3), 2-methoxyethyl (-CH2CH2OCH3), and 2-ethoxyethyl.

[0036] As used herein, the term "C2-C4 alkylene" is defined as a saturated divalent hydrocarbon group having 2 to 4 carbon atoms.

[0037] "C3-C 30 The term "cycloalkyl" is understood to mean a saturated, monocyclic, bicyclic or tricyclic hydrocarbon group having 3 to 30 carbon atoms, which may be substituted. Generally, preference is given to cycloalkyl groups (C3-C 18 cycloalkyl groups) containing 3 to 18 carbon atoms. Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantane, and norbornane.

[0038] As used herein, the term "C6-C 18 aryl" when used alone or as part of a larger moiety, such as in an "aralkyl group", refers to monocyclic, bicyclic and tricyclic ring systems which may be substituted, wherein the monocyclic ring system is aromatic or at least one of the rings of the bicyclic or tricyclic ring system is aromatic. Bicyclic and tricyclic ring systems include benzo-fused 2- to 3-membered carbocyclic rings. Exemplary aryl groups include phenyl; (C1-C4)alkylphenyl, such as tolyl and ethylphenyl; indenyl; naphthalenyl, tetrahydronaphthyl, tetrahydroindenyl; tetrahydroanthracenyl; and anthracenyl. Preference may be given to the phenyl group.

[0039] 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 be substituted. The term "alkenyl" also encompasses groups having "cis" and "trans" configurations, or "E" and "Z" configurations, as understood by those skilled in the art. However, generally, 2 to 10 (C 2-10 ) or 2 to 8 (C 2-8) The selection of an unsubstituted alkenyl group containing carbon atoms is noted. The C2-C 12 Examples of the alkenyl group 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.

[0040] As used herein, "alkylaryl" refers to an alkyl-substituted aryl group, and "substituted alkylaryl" refers to an alkylaryl group further having one or more substituents as described above. Further, as used herein, "aralkyl" means an alkyl group substituted with an aryl group as defined above.

[0041] The term "hetero" as used herein 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 group, cycloalkyl group, and aryl group as defined above that contain N, O, Si, or S as part of their structure.

[0042] 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.

[0043] 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.

[0044] Epoxides may be unsubstituted or may be inertly substituted. Exemplary inert substituents include chlorine, bromine, fluorine, and phenyl.

[0045] As used herein, the term "latent" refers to an inert functional group that can be selectively converted to a reactive functional group at an appropriate point in the synthetic procedure. The event triggering this conversion can be, inter alia, moisture, heat, or irradiation.

[0046] As used herein, the term "accelerator" refers to a chemical agent that is co-reactive with a curing agent and shortens the curing time of a composition compared to what can be achieved with the curing agent alone under equivalent conditions.

[0047] 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.

[0048] Unless otherwise specified, the viscosity of the composition described in this specification 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 (parallel plates PP25 and shear rate of 1 / s at 23°C). The measurement of the composition of the present invention is performed at different shear rates from 1.5 (1 / s) to 100 (1 / s) using parallel plates PP20.

[0049] <Epoxy resin> The composition contains an epoxy resin typically present in an amount of 15 to 75% by weight, based on the weight of the composition. The epoxy resin preferably constitutes 20 to 65% by weight, for example, 23 to 61% by weight of the composition.

[0050] Above 75%, it may have an adverse effect on lap shear strength and peel effect, while a small amount, mainly less than 15%, may result in a decrease in adhesion properties. Therefore, the above amount of epoxy resin is preferred.

[0051] Examples of the epoxy resin used in this specification 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.

[0052] 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.

[0053] As an example, the following glycidyl ethers can be mentioned as monoepoxide compounds particularly suitable for use in this specification. 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.

[0054] In one embodiment, the monoepoxide compound conforms to the following formula (I) herein. JPEG0007704753000001.jpg42159(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.)

[0055] R w , R x and R y are hydrogen, and R z is preferably a phenyl group or a C1-C8 alkyl group, more preferably a C1-C4 alkyl group.

[0056] Considering this embodiment, 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.

[0057] 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.

[0058] 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 epoxy equivalent of 100 to 700 g / eq, for example, 120 to 320 g / eq. Further, generally, diepoxide compounds having an epoxy 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 and the like, low molecular weight epoxy resins require more limited treatment in purification.

[0059] 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.

[0060] Suitable glycidyl 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 glycidyl ethers are glycidyl 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 glycidyl ethers; bisphenol F glycidyl ethers; diglycidyl o-phthalate, diglycidyl isophthalate, and diglycidyl terephthalate; polyalkylene glycol-based glycidyl ethers, especially polypropylene glycol diglycidyl ether; and polycarbonate diol-based glycidyl ethers. Other suitable diepoxides that may be mentioned further include diepoxides of double unsaturated fatty acid C1-C 18 alkyl esters; butadiene diepoxide; polybutadiene glycidyl ether; vinylcyclohexene diepoxide; and limonene diepoxide.

[0061] 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.

[0062] Also, examples of highly preferred polyepoxy compounds include bisphenol A epoxy resins such as DER™ 331, DER™ 330, DERTM 337, and DER™ 383; 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; solid bisphenol A epoxy resins such as DER™ 661 and DER™ 664 UE; solutions of bisphenol A solid epoxy resins such as DER™ 671-X75; epoxy novolac 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 the like.

[0063] Alternatively, in certain embodiments, the composition may include a glycidoxyalkylalkoxysilane having the following formula. JPEG0007704753000002.jpg945[wherein each R is independently selected from methyl or ethyl, and n is from 1 to 10.]

[0064] Exemplary silanes include, but are not limited to, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxyethyltrimethoxysilane, γ-glycidoxymethyltrimethoxysilane, γ-glycidoxymethyltriethoxysilane, γ-glycidoxyethyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, and 8-glycidoxyoctyltrimethoxysilane. When present, the epoxy-functional silane may constitute less than 20% by weight, preferably less than 10% by weight, or less than 5% by weight, based on the total weight of the epoxy compound.

[0065] The present invention also does not exclude that the curable composition further contains one or more cyclic monomers 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 comonomers 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 epoxy compound.

[0066] <Hardener> In the present invention, there is no particular intention to limit the hardeners that may be useful. For example, the hardener may include, or consist of, a reactive hardener that is a compound having at least two epoxy-reactive groups per molecule. Similarly, the hardener may include, or consist of, a latent hardener that includes a photo-latent hardener. Combinations of reactive and latent hardeners are contemplated in the present invention. Separately, the amount of hardener present in the composition must be sufficient to effect curing of the epoxy resin.

[0067] The reactive hardener may particularly include one or more of: i) at least one polyamine having at least two amine hydrogens reactive with an epoxy group; ii) at least one mercapto compound having at least two mercapto groups reactive with an epoxy group; and iii) at least one Mannich base.

[0068] At least one polyamine having at least two amine hydrogens reactive with an epoxy group particularly includes a primary amine group and / or a secondary amine group, and has an equivalent weight of 150 g / equivalent or less, preferably 125 g / eq or less, per primary amine group or secondary amine group.

[0069] Suitable polyamines that can be used alone or in combination include, but are not limited to, the following.

[0070] i) Aliphatic, alicyclic or arylaliphatic primary diamines that can be exemplified as follows: 2,2-dimethyl-1,3-propanediamine; 1,3-pentanediamine (DAMP); 1,5-pentanediamine; 1,5-diamino-2-methylpentane (MPMD); 2-butyl-2-ethyl-1,5-pentanediamine (C11-neodiamine); 1,6-hexanediamine (hexamethylenediamine, HMDA); 2,5-dimethyl-1,6-hexanediamine; 2,2,4- and / or 2,4,4-trimethylhexamethylenediamine; 1,7-heptanediamine; 1,8-octanediamine; 1,9-nonanediamine; 1,10-decanediamine; 1,11-undecanediamine; 1,12-dodecanediamine; 1,2-, 1,3- and 1,4-diaminocyclohexane; bis(4-aminocyclohexyl)methane; bis(4-amino-3-methylcyclohexyl)methane; bis(4-amino-3-ethylcyclohexyl)methane; bis(4-amino-3,5-dimethylcyclohexyl)methane; bis(4-amino-3-ethyl-5-methylcyclohexyl)methane; 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane (isophoronediamine, IPDA); 2- and / or 4-methyl-1,3-diaminocyclohexane; 1,3-bis(aminomethyl)-cyclohexane; 1,4-bis(aminomethyl)cyclohexane; 2,5(2,6)-bis(aminomethyl)-bicyclo[2.2.1]heptane (norbornanediamine, NBDA); 3(4),8(9)-bis(aminomethyl)tricyclo[5.2.1.0(2,6)]-decane (TCD-diamine); 1,4-diamino-2,2,6-trimethylcyclohexane (TMCDA); 1,8-menthanediamine; 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5.5]undecane; and, 1,3-bis(aminomethyl)benzene (MXDA).

[0071] ii) Tertiary amine group-containing polyamines having two or three primary aliphatic amine groups, which can include the following specific examples: N,N'-bis(aminopropyl)-piperazine; N,N-bis(3-aminopropyl)methylamine; N,N-bis(3-aminopropyl)ethylamine; N,N-bis(3-aminopropyl)propylamine; N,N-bis(3-aminopropyl)cyclohexylamine; N,N-bis(3-aminopropyl)-2-ethyl-hexylamine; tris(2-aminoethyl)amine; tris(2-aminopropyl)amine; tris(3-aminopropyl)amine; and products from the dicyanoethylation of fatty amines derived from natural fatty acids followed by reduction, such as N,N-bis(3-aminopropyl)dodecylamine and N,N-bis(3-aminopropyl)tallow alkylamine, which are commercially available as Triameen® Y12D and Triameen® YT (manufactured by Akzo Nobel).

[0072] iii) Ether group-containing aliphatic primary polyamines that can include the following specific examples: bis(2-aminoethyl) ether; 3,6-dioxaoctane-1,8-diamine; 4,7-dioxadecane-1,10-diamine; 4,7-dioxadecane-2,9-diamine; 4,9-dioxadodecane-1,12-diamine; 5,8-dioxadodecane-3,10-diamine; 4,7,10-trioxatridecane-1,13-diamine, and higher oligomers of these diamines; bis(3-aminopropyl) polytetrahydrofuran, and other polytetrahydrofuran diamines; alicyclic ether group-containing diamines obtained from the propoxylation of 1,4-dimethylolcyclohexane and subsequent amination, such as materials commercially available as Jeffamine® RFD-270 (manufactured by Huntsman); products obtained from the amination of polyoxyalkylene diols and polyoxyalkylene triols, polyoxyalkylene diamines or polyoxyalkylene triamines available under the names Jeffamine® (manufactured by Huntsman), polyetheramine (manufactured by BASF), or PCAmines® (manufactured by Nitroil). The use of Jeffamine® D-230, Jeffamine® D-400, Jeffamine® D-600, Jeffamine® D-2000, Jeffamine® D-4000, Jeffamine® T-403, Jeffamine® T-3000, Jeffamine® T-5000, Jeffamine® EDR-104, Jeffamine® EDR-148, and Jeffamine® EDR-176, as well as the corresponding amines manufactured by BASF or Nitroil, may be particularly suitable.

[0073] iv) Primary diamines having a secondary amine group, which may include the following examples: 3-(2-aminoethyl)aminopropylamine, bis(hexamethylene)triamine (BHMT); diethylenetriamine (DETA); triethylenetetramine (TETA); tetraethylenepentamine (TEPA); pentaethylenehexamine (PEHA); higher homologues of linear polyethyleneamines, such as polyethylene polyamines having 5 to 7 ethyleneamine units (so-called "higher ethylene polyamines", HEPA), etc.; products from the multi-step cyanoethylation or cyanobutylation of primary diamines and polyamines having at least two primary amine groups and subsequent hydrogenation, such as dipropylenetriamine (DPTA), N-(2-aminoethyl)-1,3-propanediamine (N3-amine), N,N'-bis(3-aminopropyl)ethylenediamine (N4-amine), N,N'-bis(3-aminopropyl)-1,4-diaminobutane, N5-(3-aminopropyl)-2-methyl-1,5-pentanediamine, N3-(3-aminopentyl)-1,3-pentanediamine, N5-(3-amino-1-ethylpropyl)-2-methyl-1,5-pentanediamine, or N,N'-bis(3-amino-1-ethylpropyl)-2-methyl-1,5-pentanediamine.

[0074] v) Polyamines having one primary amino group and at least one secondary amino group, which may include the following examples: N-butyl-1,2-ethanediamine; N-hexyl-1,2-ethanediamine; N-(2-ethylhexyl)-1,2-ethanediamine; N-cyclohexyl-1,2-ethanediamine; 4-aminomethyl-piperidine; N-(2-aminoethyl)piperazine; N-methyl-1,3-propanediamine; N-butyl-1,3-propanediamine; N-(2-ethylhexyl)-1,3-propanediamine; N-cyclohexyl-1,3-propanediamine; 3-methylamino-1-pentylamine; 3-ethylamino-1-pentylamine; 3-cyclohexylamino-1-pentylamine; aliphatic diamines such as N-cocoalkyl-1,3-propanediamine; products from Michael-type addition reactions of primary aliphatic diamines reacted in a 1:1 molar ratio with acrylonitrile, maleic acid or fumaric acid diesters, citraconic acid diesters, acrylic acid and methacrylic acid esters, acrylic acid and methacrylic acid amides, and itaconic acid diesters; products from partial reductive alkylation of primary polyamines with aldehydes or ketones, particularly the aforementioned polyamines having two primary amine groups, particularly 1,6-hexanediamine, 1,5-diamino-2-methylpentane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-bis(aminomethyl)benzene, BHMT, DETA, TETA, TEPA, DPTA, N-monoalkylation products of N3-amine and N4-amine (wherein the preferred alkyl groups are benzyl, isobutyl, hexyl, 2-ethylhexyl); and partially styrenated polyamines such as those commercially available as Gaskamine® 240 (manufactured by Mitsubishi Gas Chemical).

[0075] vi) Secondary diamines, in particular the above-mentioned polyamines having two primary amine groups, in particular 1,6-hexanediamine, 1,5-diamino-2-methylpentane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)-cyclohexane, 1,3-bis(aminomethyl)benzene, BHMT, DETA, TETA, TEPA, DPTA, N3-amine or N4-amine N,N'-dialkylation products (wherein the preferred alkyl groups are 2-phenylethyl, benzyl, isobutyl, hexyl and 2-ethylhexyl).

[0076] vii) Aromatic polyamines that can be mentioned below: m- and p-phenylenediamine, 4,4'-, 2,4'- and 2,2'-diaminodiphenylmethane; 3,3'-dichloro-4,4'-diaminodiphenylmethane (MOCA); 2,4- and 2,6-tolylenediamine; a mixture of 3,5-dimethylthio-2,4- and -2,6-tolylenediamine (available from Albermarle as Ethacure® 300); a mixture of 3,5-diethyl-2,4- and -2,6-tolylenediamine (DETDA); 3,3',5,5'-tetraethyl-4,4'-diaminodiphenylmethane (M-DEA); 3,3',5,5'-tetraethyl-2,2'-dichloro-4,4'-diaminodiphenylmethane (M-CDEA); 3,3'-diisopropyl-5,5'-dimethyl-4,4'-diaminodiphenylmethane (M-MIPA); 3,3',5,5'-tetraisopropyl-4,4'-diaminodiphenylmethane (M-DIPA); 4,4'-diaminodiphenylsulfone (DDS); 4-amino-N-(4-aminophenyl)benzenesulfonamide; 5,5'-methylenediantranilic acid; dimethyl-(5,5'-methylenediantranilate); 1,3-propylene-bis(4-aminobenzoate); 1,4-butylene-bis(4-aminobenzoate); polytetramethyleneoxide-bis(4-aminobenzoate) (available from Air Products as Versalink®); 1,2-bis(2-aminophenylthio)ethane, 2-methylpropyl-(4-chloro-3,5-diaminobenzoate); and tert-butyl-(4-chloro-3,5-diaminobenzoate).

[0077] viii) The described composition comprises a polyamideamine that is a reaction product of a monovalent or polyvalent carboxylic acid, or its ester or anhydride, in particular a dimer fatty acid, and an aliphatic, alicyclic or aromatic polyamine, such as a polyalkyleneamine like DETA or TETA. Commercially available polyamideamines include the following: Versamid® 100, 125, 140, and 150 (manufactured by Cognis); Aradur® 223, 250, and 848 (manufactured by Huntsman); Euretek® 3607 and 530 (manufactured by Huntsman); and Beckopox® EH651, EH654, EH655, EH661 and EH663 (manufactured by Cytec).

[0078] Among the aforementioned polyamines having at least two primary aliphatic amine groups, preferred ones are isophoronediamine (IPDA); hexamethylenediamine (HMDA); 1,3-bis(aminomethyl)cyclohexane; 1,4-bis(aminomethyl)cyclohexane; bis(4-aminocyclohexyl)methane; bis(4-amino-3-methylcyclohexyl)methane; NBDA; and ether group-containing polyamines having a number average molecular weight (Mn) of up to 500 g / mol. Particularly preferred among the ether group-containing polyamines are Jeffamine® D-230 and D-600 (available from Huntsman).

[0079] As described above, the composition of the present invention may optionally include, as a reactive curing agent, at least one compound having at least two reactive mercapto groups per molecule. Suitable mercapto group-containing compounds that can be used alone or in combination include, but are not limited to, the following.

[0080] · Liquid mercaptan-terminated polysulfide polymers, and as commercial examples thereof, Thiokol® polymers (available from Morton Thiokol), in particular, its type numbers LP-3, LP-33, LP-980, LP-23, LP-55, LP-56, LP-12, LP-31, LP-32 and LP-2; and, Thioplast® polymers (manufactured by Akzo Nobel), in particular, type numbers G10, G112, G131, G1, G12, G21, G22, G44 and G4. · Mercaptan-terminated polyoxyalkylene ethers which can be obtained by reacting polyoxyalkylene diols and polyoxyalkylene triols with epichlorohydrin or alkylene oxides and subsequently reacting with sodium hydrogen sulfide. · Mercaptan-terminated compounds in the form of polyoxyalkylene derivatives known by the trade name Capcure® (manufactured by Cognis), in particular its type numbers WR-8, LOF and 3-800. · As specific examples, polyesters of thiocarboxylic acids, including pentaerythritol tetramercaptoacetate (PETMP); trimethylolpropane trimercaptoacetate (TMPMP); glycol dimercaptoacetate; and, esterification products of polyoxyalkylene diols and triols, ethoxylated trimethylolpropane and polyester diols with thiocarboxylic acids such as thioglycolic acid and 2- or 3-mercaptopropionic acid. · 2,4,6-trimercapto-1,3,5-triazine, 2,2'-(ethylenedioxy)-diethanethiol (triethylene glycol dimercaptan) and / or ethanedithiol. · Tris(2-(mercaptopropionyloxy)ethyl) isocyanate. · The use of polyesters of thiocarboxylic acids, in particular pentaerythritol tetramercaptoacetate (PETMP), tris-(3-mercaptopropionate) (TMP), trimethylolpropane trimercaptoacetate (TMPMP), tris(2-(mercaptopropionyloxy)ethyl) isocyanate and glycol dimercaptoacetate is recognized as preferred.

[0081] As described above, the reactive curing agent may contain at least one Mannich base. Such compounds may be characterized by containing at least one phenalkamine, and in particular, phenalkamines obtained from the condensation of cardanol (CAS number: 37330-39-5), aldehydes and amines. The reactant amine in the condensation reaction is preferably ethylenediamine or diethyltriamine.

[0082] Mannich bases and phenalkamines are known in the art, and suitable examples include commercially available phenalkamines such as Cardolite® NC-541, NC-557, NC-558, NC-566, Lite2001 and Lite2002 (available from Cardolite), Aradur® 3440, 3441, 3442 and 3460 (available from Huntsman) and Beckopox® EH614, EH621, EH624, EH628 and EH629 (available from Cytec).

[0083] Any common latent epoxy curing agent used in the art can be used in the present invention without particular limitation. For example, suitable latent epoxy curing agents that can be used herein are described in U.S. Patent No. 4,546,155; U.S. Patent No. 7,226,976; U.S. Patent No. 4,833,226; JP-A-2008-214567; British Patent No. 1,121,196; International Application Publication No. 2014 / 165423; and U.S. Patent No. 5,077,376. Examples of commercially available latent epoxy curing agents include Amicure PN-23, PN-40, PN-H, MY-24, and PN-50 commercially available from Ajinomoto Co., Inc.; EH-4337S, EH-3293S, and EH-4357S commercially available from Asahi Denka Co., Ltd., Novacure HX-3722 and HXA-3921HP commercially available from Asahi Kasei Chemicals Corporation; Sunmide LH-210, Ancamin 2014AS / FG, and Ancamin 2337S commercially available from Air Products and Chemicals, Inc., and the like.

[0084] As is known in the art, dicyandiamide has found general utility as a latent epoxy curing agent and can actually be used in the present composition. When used, the dicyandiamide is preferably in a finely pulverized form (with an average particle diameter (d50) of 0.5 to 100 μm, for example 1 to 50 μm or 2 to 20 μm). The particle diameter refers to the diameter or maximum dimension of the particles in the particle distribution and can be measured via dynamic light scattering.

[0085] Further exemplary potential epoxy curing agents include ketimines obtained by the reaction of aliphatic polyamines with ketones; polyethyleneimines, especially polyethyleneimines with a weight average molecular weight (Mw) of 700 to 1,000,000; imidazole derivatives such as 2-heptadeoyl imidazole, 2-phenyl-4,5-dihydroxymethyl imidazole, 2-phenyl-4-methyl-5-hydroxymethyl imidazole, 2-phenyl-4-benzyl-5-hydroxymethyl-imidazole, etc.; 2,4-diamino-8-2-methylimidazolyl-(1)-ethyl-5-triazine; addition products of triazine and isocyanuric acid; hydrazides such as succinohydrazide, adipic dihydrazide, isophthalohydrazide, o-oxybenzohydrazide, and salicylhydrazide, etc., but are not limited thereto.

[0086] When preparing the curable composition, it is preferable that the composition contains 0.01 to 25% by weight of the curing agent for the epoxy resin based on the weight of the composition. Preferably, the composition contains 0.1 to 23% by weight, for example, 0.5 to 21% by weight of the curing agent.

[0087] An amount exceeding 25% may result in excessive free amines in the composition and may adversely affect the lap shear strength. On the other hand, a small amount mainly less than 0.01% may result in incomplete curing. Therefore, the above amount of the curing agent is preferable.

[0088] <Accelerator> The composition of the present invention should preferably contain at least one accelerator, which is a substance that promotes the reaction between the epoxy group and the epoxy-reactive group of the curing agent, for example, the reaction between an amine or thiol group and an epoxy group. A specific example relates to the use of amine accelerators that function by deprotonating the existing reactive thiol (-SH) groups to thiolates (-S'') and the thiolates reacting with epoxy groups by nucleophilic ring-opening polymerization.

[0089] Although there is no intention to limit the accelerators used in the present invention, the following suitable accelerators may be mentioned. i) Acids or compounds hydrolyzable to acids, particularly a) organic carboxylic acids such as acetic acid, benzoic acid, salicylic acid, 2-nitrobenzoic acid and lactic acid; b) organic sulfonic acids such as methanesulfonic acid, p-toluenesulfonic acid and 4-dodecylbenzenesulfonic acid; c) sulfonic acid esters; d) inorganic acids such as phosphoric acid; e) Lewis acid compounds such as BF3 amine complexes, SbF6 sulfonium compounds, bisarene iron complexes; f) Bronsted acid compounds such as pentafluoroantimonic acid complexes; and, e) mixtures of the above acids and acid esters; i) phenols, particularly bisphenols; ii) tertiary amines such as 2-piperazin-1-ylethylamine, 1,4-diazabicyclo[2.2.2]octane, benzyldimethylamine, α-methylbenzyldimethylamine, triethanolamine, dimethylaminopropylamine, imidazoles (including N-methylimidazole, N-vinylimidazole and 1,2-dimethylimidazole) and salts of such tertiary amines; iii) quaternary ammonium salts such as benzyltrimethylammonium chloride; iv) amidines such as 1,8-diazabicyclo[5.4.0]undec-7-ene; v) guanidines such as 1,1,3,3-tetramethylguanidine; iv) phenolic resins; and v) phosphites such as diphenyl phosphite and triphenyl phosphite.

[0090] Those skilled in the art will recognize that the choice of accelerator is not simply a matter of adding the fastest accelerator. Other decisive factors in the choice of accelerator include cost; toxicity; solubility; processing effects such as working time, early gelation, thermal decomposition, swelling and gas evolution; final properties such as glass transition temperature (Tg), modulus of elasticity, strength, elongation at break and chemical resistance; regulatory matters; and ease of use.

[0091] In the present invention, it is preferable to use an accelerator comprising at least one tertiary amine, at least one amidine, or a mixture thereof, or consisting of the same. More specifically, the accelerator should be selected from the group consisting of imidazole, methylimidazole, benzyldimethylamine, 1,8-diazabicyclo[5.4.0]undec-7-ene, 1,4-diazabicyclo(2,2,2)octane, and mixtures thereof.

[0092] The accelerator is desirably present in the composition in an amount of 0.1 to 15% by weight, based on the weight of the composition. The accelerator may preferably constitute 1 to 10% by weight, for example, 5 to 10% by weight of the composition.

[0093] When the amount of the accelerator exceeds 15%, the accelerator in the composition becomes excessive, which may adversely affect the curing process and adhesion properties. On the other hand, when the amount is mainly less than 0.01%, the physical effect may disappear. Therefore, the above amount of the accelerator is preferable.

[0094] <Electrolyte> The composition contains 2 to 25% by weight of an electrolyte, based on the weight of the composition. The electrolyte may preferably constitute 3 to 20% by weight, for example, 5 to 18% by weight of the composition.

[0095] An amount exceeding 25% can bring about a good peeling effect, but curing may become incomplete and may adversely affect the initial adhesion properties. On the other hand, when the amount is mainly less than 2%, the lack of a peeling effect may occur. Therefore, the above amount of the electrolyte is preferable.

[0096] The electrolyte preferably contains at least one salt having a formula selected from the group consisting of the following. JPEG0007704753000003.jpg103117(wherein R 1 、R 2 、R 3 、R 4 、R 5 and R 6 are independently hydrogen, C1-C 18 alkyl, C3-C 18Cycloalkyl, C6-C 18 Aryl, C7-C 24 Aralkyl, C2-C 20 Alkenyl, -C(O)R q , -C(O)OH, -CN and -NO2, and R q is C1-C6 alkyl.)

[0097] To complete, C1-C 18 Alkyl, C3-C 18 Cycloalkyl, C6-C 18 Aryl, C7-C 24 Aralkyl, C2-C 20 The term alkenyl includes groups in which one or more hydrogen atoms are replaced by halogen atoms (e.g., C1-C 18 haloalkyl) or groups replaced by hydroxyl groups (e.g., C1-C 18 hydroxyalkyl). In particular, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are, independently, hydrogen, C1-C 12 alkyl, C1-C 12 haloalkyl, C1-C 12 hydroxyalkyl and C3-C 12 cycloalkyl. For example, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 can be, independently, hydrogen, C1-C6 alkyl, C1-C6 haloalkyl and C1-C6 hydroxyalkyl.)

[0098] There is no specific intention to limit the counteranion (X - ) that can be used in the electrolyte. Exemplary anions can be selected from the following. · Halide; · The formula PF6 - , CF3SO3 - , (CF3SO3)2N- , CF3CO2 - and CCl3CO2 - pseudo-halides and halogen-containing compounds of; ·CN - , SCN - and OCN - ; ·phenate; ·general formula SO4 2- , HSO4 - , SO3 2- , HSO3 - , R a OSO3 - and R a SO3 - sulfates, sulfites and sulfonates of; ·general formula PO4 3- , HPO4 2- , H2PO4 - , R a PO4 2- , HR a PO4 - and R a R b PO4 - phosphates of; ·general formula R a HPO3 - , R a R b PO2 - , and R a R b PO3 - phosphonates and phosphinates of; ·general formula PO3 3- , HPO3 2- , H2PO3 - , R a PO3 2- , R a HPO3 - and R a R b PO3 - phosphites of; ·general formula R a R b PO2 - , R a HPO2 - , R a R b PO- and R a HPO - phosphonites and phosphinites of; · General formula R a COO - carboxylate anions of; · hydroxycarboxylate anions and saccharate anions; · saccharinate (salt of o-benzoic sulfimide); · General formula BO3 3- , HBO3 2- , H2BO3 - , R a R b BO3 - , R a HBO3 - , R a BO3 2- , B(OR a )(OR b )(OR c )(OR d ) - , B(HSO4) - and B(R a SO4) - borates of; · General formula R a BO2 2- and R a R b BO - boronates of; · General formula HCO3 - , CO3 2- and R a CO3 - carbonates and carbonic esters of; · General formula SiO4 4- , HSiO4 3- , H2SiO4 2- , H3SiO4 - , R a SiO4 3- , R a R b SiО4 2- , R a R b R c SiO4 - , HR a SiO4 2- , H2R aSiO4 - and HR a R b SiO4 - silicates and silicic acid esters of; · General formula R a SiO3 3- 、R a R b SiO2 2- 、R a R b R c SiO - 、R a R b R c SiO3 - 、R a R b R c SiO2 - and R a R b SiO3 2- alkyl and aryl silanolates of; · Pyridinates and pyrimidinates; · General formula: carboxylic acid imides, bis(sulfonyl)imides and sulfonylimides of JPEG0007704753000004.jpg41155; · General formula: methides of JPEG0007704753000005.jpg3394; · General formula R a O - alkoxides and aryloxides of; and, · General formula S 2- 、HS - 、[Sv] 2- 、[HSv] - 、and [RaS] - sulfides, hydrogen sulfide, polysulfides, polysulfane, and thiolates of (in the general formula, v is a positive integer from 2 to 10, and R a 、R b 、R c and R d are independently hydrogen, C1-C 12 alkyl, C5-C 12 cycloalkyl, C5-C 12 heterocycloalkyl, C6-C 18Selected from aryl and C5-C 18 heteroaryl.)

[0099] Based on the definitions in the above list, preferred anions are the halides, pseudohalides and halogen-containing compounds defined above; carboxylate anions, especially formate, acetate, propionate, butyrate and lactate; hydroxycarboxylate anions; pyridinates and pyrimidinates; carboximides, bis(sulfonyl)imides and sulfonylimides; sulfates, especially methyl sulfate and ethyl sulfate; sulfites; sulfonates, especially methanesulfonate; and phosphates, especially dimethyl phosphate, diethyl phosphate and di-(2-ethylhexyl)-phosphate, selected from the group consisting of

[0100] The electrolyte is preferably 1-ethyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium methyl sulfate, 1-hexyl-3-methylimidazolium 2-(2-fluoroanilino)-pyridinate, 1-hexyl-3-methylimidazolium imide, 1-butyl-1-methyl-pyrrolidinium 2-(2-fluoroanilino)-pyridinate, 1-butyl-1-methyl-pyrrolidinium imide, trihexyl(tetradecyl)phosphonium 2-(2-fluoroanilino)-pyridinate, cyclohexyltrimethylammonium bis(trifluoromethylsulfonyl)imide, di(2-hydroxyethyl)ammonium acetate, N,N-dimethyl(2-hydroxyethyl)ammonium octanoate, methyltrioctylammonium bis(trifluoromethylsulfonyl)imide, N-ethyl-N-N-N-N-tetramethylguanidinium trifluoromethanesulfonate, guanidinium trifluoromethanesulfonate, 1-butyl-4-methylpyridinium bromide, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-3-hydroxymethylpyridinium ethyl sulfate, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, 1-butyl-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate, 3-methylimidazolium ethyl sulfate, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-ethyl-methylimidazolium bromide, 1-butyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium chloride, 1-octyl-3-methylimidazolium chloride, 1-methyl-3-octylimidazolium chloride, 1-propyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, 1-butyl-2,It is selected from the group consisting of 3-dimethylimidazolium hexafluorophosphate, 1-butylimidazole, 1-methylimidazolium tetrafluoroborate, tetrabutylphosphonium tris(pentafluoroethyl)trifluorophosphate, trihexyl(tetradecyl)phosphonium tetrafluoroborate, and mixtures thereof. It is particularly preferred to use at least one of 1-ethyl-3-methylimidazolium methanesulfonate and 1-ethyl-3-methylimidazolium methyl sulfate.,

[0101] The above electrolyte is preferred because it provides good stability to the composition, good initial adhesion strength, and potentially good peeling effect when treated.,

[0102] <Electrically non-conductive filler> The composition of the present invention is characterized by the presence of a non-conductive filler. Generally, there is no special intention to limit the shape of the particles used as the non-conductive filler, 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 0.1 to 1500 μm, for example 1 to 1000 μm or 1 to 500 μm, measured by the laser diffraction / scattering method.,

[0103] Exemplary non-conductive fillers include, but are not limited to, chalk, lime powder, precipitated and / or pyrogenic silica, zeolite, bentonite, magnesium carbonate, diatomaceous earth, alumina, clay, talc, sand, quartz, flint, mica, glass powder, and other crushed mineral substances. Short fibers, such as glass fibers, glass filaments, polyacrylonitrile, carbon fibers, or polyethylene fibers, etc. can also be added.,

[0104] Pyrogenic and / or precipitated silica is preferably 10 to 90 m 2It has a BET specific surface area of / g. When they are used, no further increase in the viscosity of the composition of the present invention is caused, and it contributes to the strengthening of the cured composition.

[0105] Similarly, it is conceivable to use pyrogenic and / or precipitated silicas having a higher, preferably 100 to 250 m 2 / g BET specific surface area as a filler. Due to the larger BET specific surface area, the effect of strengthening the cured composition with a smaller weight ratio of silica is achieved.

[0106] Also suitable as non-conductive fillers 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), etc. 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, preferably 100 μm to 200 μm respectively.

[0107] Non-conductive fillers that impart thixotropy to the composition may be suitable for many applications. Such fillers are also described as rheology aids, such as hydrogenated castor oil, fatty acid amides, or swelling plastics such as PVC.

[0108] Preferably, the non-conductive filler is selected from the group consisting of calcium carbonate, calcium oxide, talc, fumed silica, silica, wollastonite, barium sulfate, and mixtures thereof.

[0109] In a highly preferred embodiment, the composition of the present invention contains fumed silica as a non-conductive filler.

[0110] To dissolve the electrolyte in the composition and avoid phase separation, the electrolyte may need to be hydrophobic. Conductive fillers, especially fumed silica, provide the required hydrophobicity to the composition, improve the solubility of the electrolyte, and prevent phase separation. Further, technical data shows that the presence of non-conductive fillers improves the initial adhesion performance of the composition.

[0111] The desired viscosity of the curable composition to be formed can determine the amount of filler used. Considering the latter, the total amount of both conductive and non-conductive fillers present in the composition should not prevent the composition from being easily extruded from a suitable dispensing device such as a tube. The viscosity is usually 3000 - 200,000000 mPas, preferably 20,000 - 100,000 mPas, more preferably 40,000 - 80,000 mPas, and even more preferably 50,000 - 60,000 mPas.

[0112] Apart from the above viscosity conditions, the non-conductive filler is preferably present in an amount of 1 - 50 wt%, preferably 1.5 - 48 wt%, more preferably 2 - 47 wt% of the total weight of the composition.

[0113] An amount exceeding 50% may result in insufficient adhesion properties, while a small amount mainly less than 1% may cause problems with insufficient adhesion properties and viscosity. Therefore, the above amount of the non-conductive filler is preferred.

[0114] <Combination of solubilizer and strengthening agent> The solubilizer has the function of promoting the miscibility of the electrolyte in the adhesive composition. 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.

[0115] Suitable classes of solubilizers include polyphosphazenes; polymethylene sulfide; polyoxyalkylene glycols; polyethyleneimine; silicone surfactants such as polyalkylsiloxanes and polyoxyalkylene-modified polydimethylsiloxanes (including, but not limited to, poly(C2-C3)oxyalkylene-modified polydimethylsiloxanes); copolymers of functionalized polyalkylsiloxanes and epoxy resins, such as copolymers of polydimethylsiloxane (PDMS) and epoxy resins; polyhydric alcohols; and saccharides. For completeness, fluorinated silicone surfactants such as fluorinated polysilanes are intended to be included within the term silicone surfactants.

[0116] Polyhydric alcohols and saccharides such as ethylene glycol, 1,3-propanediol, cyclohexanediol, hydroquinone, catechol, resorcinol, phloroglucinol, pyrogallol, hydroxyhydroquinone, tris(hydroxymethyl)benzene, tris(hydroxymethyl)benzene with three methyl or ethyl substituents bonded to the remaining carbon atoms of benzene, isosorbide, isomannide, isoidide, glycerol, cyclohexane-1,2,4-triol, 1,3,5-cyclohexanetriol, pentane-1,2,3-triol, hexane-1,3,5-triol, erythritol, 1,2,4,5-tetrahydroxybenzene, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, inositol, fructose, glucose, mannose, lactose, 1,1,1-tris(hydroxymethyl)propane, 1,1,1-tris(hydroxymethyl)ethane, di(trimethylolpropane), trimethylolpropane ethoxylate, 2-hydroxymethyl-1,3-propanediol, pentaerythritol allyl ether and pentaerythritol.

[0117] Among the polyoxyalkylene glycols, the use of polyoxy(C2-C3)alkylene glycols having a weight average molecular weight of 200 to 10,000 g / mol, for example 200 to 2,000 g / mol, can be said to be particularly preferred.

[0118] The presence of a reinforcing agent in the composition of the present invention can be advantageous for the peeling of the cured adhesive when the reinforcing agent is included together with a solubilizing agent. Without intending to be bound by theory, the reinforcing agent promotes phase separation in the cured adhesive under the application of a potential. In particular, good peeling results were obtained when the composition of the present invention included at least one reinforcing agent selected from epoxy-elastomer adducts and reinforcing rubbers in the form of core-shell particles dispersed in an epoxy resin matrix.

[0119] The elastomer-containing adducts can be used separately or in combination of two or more specific adducts. Further, each adduct can be independently selected from solid adducts or liquid adducts at a temperature of 23°C. Usually, useful adducts are characterized in that the weight ratio of epoxy to elastomer is from 1:5 to 5:1, for example from 1:3 to 3:1. Also, a useful reference regarding suitable epoxy / elastomer adducts is US Patent Application Publication No. 2004 / 0204551. Further, exemplary commercially available epoxy / elastomer adducts used herein include, but are not limited to, HYPDX RK8-4 commercially available from CVC Chemical and B-Tough A3 available from Croda Europe Limited.

[0120] The term "core-shell rubber" or CSR is used according to its standard meaning in the art to denote a rubber particle core formed by a polymer containing an elastic or rubbery polymer as a main component and a shell layer formed by a graft-polymerized polymer on the core. The shell layer partially or completely covers the surface of the rubber particle core in the graft polymerization process. By weight, the core must constitute at least 50% by weight of the core-shell rubber particles.

[0121] 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.

[0122] Without intending to limit the present invention, the core can be composed of a diene homopolymer, such as a homopolymer of butadiene or isoprene; a diene copolymer, such as a copolymer of 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.

[0123] 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.

[0124] 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. In order to achieve perfection, 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.

[0125] 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 available from Kaneka Corporation, particularly MX120, MX125, MX130, MX136, MX551, MX553; and METABLEN SX-006 available from Mitsubishi Rayon.

[0126] In those embodiments of the present invention in which there is a combination of a solubilizing agent and a reinforcing agent, the reinforcing agent is preferably contained in the composition in an amount of 5 to 40% by weight, for example 10 to 25% by weight or 12 to 16% by weight, based on the total weight of the composition, the solubilizing agent is preferably contained in an amount of 1 to 15% by weight, preferably the solubilizing agent constitutes 2 to 10% by weight, for example 3 to 7% by weight, of the composition.

[0127] When the amount of the reinforcing agent exceeds 40%, it may result in insufficient adhesion properties, while a small amount mainly less than 5% may result in an insufficient peeling effect and the flexibility of the composition may become too high. Therefore, the above amounts are preferred.

[0128] Furthermore, while amounts of solubilizing agent in excess of 15% may adversely affect adhesion and curing characteristics, while small amounts mainly less than 1% may make the composition more viscous / solid and may impede mixing of components, the amounts described above are preferred.

[0129] <Conductive particles> Instead of, or in addition to, the presence of the aforementioned combination of solubilizing agent and reinforcing agent, the composition of the present invention may contain conductive particles.

[0130] Applicants have surprisingly found that addition of conductive particles to the composition of the present invention can reduce the amount of electrolyte while maintaining good peel characteristics.

[0131] There is no particular intention to limit the shape of the particles generally used as conductive fillers. Needle-shaped, spherical, elliptical, cylindrical, bead-shaped, cubic or platelet-shaped particles can be used alone or in combination. Furthermore, aggregates of multiple types of particles are considered to be usable. Similarly, there is no particular intention to limit the particle size used as the conductive filler. However, such conductive fillers conventionally have an average volume particle size of 1 to 500 μm, for example 1 to 200 μm, as measured by the laser diffraction / scattering method.

[0132] Exemplary conductive particles (fillers) include, but are not limited to, silver, copper, gold, palladium, platinum, nickel, gold-coated or silver-coated nickel, carbon black, carbon fiber, graphite, aluminum, indium tin oxide, silver-coated copper, silver-coated aluminum, metal-coated glass spheres, metal-coated fillers, metal-coated polymers, silver-coated fibers, silver-coated spheres, antimony-doped tin oxide, conductive nanospheres, nano silver, nano aluminum, nano copper, nano nickel, carbon nanotubes, and mixtures thereof. It is preferred to use particulate silver and / or carbon black as the conductive filler.

[0133] In certain important embodiments, the conductive particles may be included in the composition in an amount of 0.05 to 10% by weight, based on the total weight of the composition. Preferably, the composition includes 0.1 to 5% by weight, such as 0.5 to 4% by weight or 1 to 3% by weight, of conductive particles (fillers), based on the total weight of the composition.

[0134] An amount exceeding 10% can increase conductivity but may simultaneously have an adverse effect on adhesion and peel properties. On the other hand, a small amount mainly less than 0.05% may not bring about a physical effect and cannot reduce the amount of electrolyte. Therefore, the above amount of conductive particles is preferred.

[0135] <Additives and Auxiliary Components> The above compositions obtained by the present invention usually further include auxiliaries and additives that can impart improved properties to these compositions. For example, the auxiliaries and additives can impart one or more of improved elastic properties; improved elastic recovery; a longer processable time; a faster curing time; and low residual tack. Among such auxiliaries and additives that can be included are plasticizers; stabilizers such as ultraviolet stabilizers; antioxidants; reactive diluents; drying agents; adhesion promoters; bactericides; flame retardants; rheology aids; coloring pigments or color pastes; and / or, optionally further, a small amount of non-reactive diluents.

[0136] Such auxiliaries and additives can be used in the desired combinations and ratios, provided that they do not adversely affect the nature and essential properties of the composition. Although there may be exceptions, these auxiliaries and additives as a whole should not exceed 50% by weight of the total composition, and preferably should not exceed 20% by weight of the composition.

[0137] The "plasticizer" for the purposes of the present invention is a substance that reduces the viscosity of the composition and promotes its processability. In this specification, the plasticizer may constitute up to 10% by weight or up to 5% by weight, based on the total weight of the composition, and preferably is diurethane; monofunctional, linear or branched C4-C 16Ethers of alcohols, such as Cetiol OE (available from Cognis Deutschland Gmbh, Düsseldorf); esters of abietic acid, butyric acid, thiobutyric acid, acetic acid, 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; phosphate esters; sulfonic acid esters; trimellitic acid esters; polyether plasticizers, such as end-capped polyethylene or polypropylene glycol, etc.; 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 because of their potential toxicity.

[0138] The "stabilizer" for the purposes of the present invention should be understood as an antioxidant, a UV stabilizer, a heat stabilizer or a hydrolysis stabilizer. In the present specification, the stabilizer may constitute up to 10% by weight or up to 5% by weight in total, based on the total weight of the composition. Standard commercially available examples of stabilizers suitable for use herein include sterically hindered phenols; thioethers; benzotriazoles; benzophenones; benzoates; cyanoacrylates; acrylates; amines of the hindered amine light stabilizer (HALS) type; phosphorus; sulfur; and mixtures thereof.

[0139] 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 or the sealant 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% by weight, for example from 0 to 5% by weight, based on the total weight of the composition.

[0140] The presence of solvents and non-reactive diluents in the composition of the present invention is also not excluded if the viscosity can thereby be effectively suppressed. 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 sulfonates; and sulfonamides.

[0141] 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.

[0142] <Methods and Applications> To form the composition, the above components are brought together and mixed. As is known in the art, to form a one-component (1K) curable composition, the elements of the composition are brought together and uniformly mixed under conditions that inhibit or prevent the reaction of the reactive components. This can include mixing conditions that limit or prevent exposure to moisture, heat, or irradiation, or that limit or prevent activation of latent catalyst components. Thus, in many cases, the curable components are preferably mixed in predetermined amounts under anhydrous conditions without intentional heating by a machine (e.g., a speed mixer, a static or dynamic mixer), rather than by hand.

[0143] According to the broadest method aspect of the present invention, the above composition is applied to a material layer and then cured in place. Prior to applying the composition, it is often recommended to pretreat the relevant surface to remove foreign matter therefrom. This step, where applicable, facilitates the subsequent adhesion of the composition. Such treatments are known in the art and can be carried out in a one-step or multi-step process consisting of, 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 use of one or more of rinsing with water, preferably deionized water or demineralized water. 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.

[0144] Next, the composition is preferably applied to the surface of the pretreated substrate by conventional coating methods such as brushing; roll coating using a four-roll coating device when the composition is solvent-free, or a two-roll coating device for solvent-containing compositions; doctor blade coating; printing methods; and spraying methods such as air spray, air-assisted spray, airless spray, and high-volume low-pressure spray, but not limited thereto.

[0145] As described above, the present invention includes a first material layer having a conductive surface; and a second material layer having a conductive surface, and a cured, peelable one - component (1K) adhesive composition as defined herein and in the appended claims provides an adhesive structure 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 and / or second material layers, and then the two layers are brought into contact, optionally under pressure, such that an electrically peelable hot - melt adhesive composition is interposed between the two layers.

[0146] The composition is preferably applied to the surface with a wet film thickness of 10 - 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 carried out when applying a thinner coating or layer.

[0147] Curing of the applied composition of the present invention typically occurs in the temperature range of 40 °C to 200 °C, preferably 50 °C to 190 °C, particularly 60 °C to 180 °C. The appropriate temperature depends on the specific compounds present and the desired curing rate and can be determined in each case by a person skilled in the art using simple preliminary tests if necessary. Naturally, curing at a lower temperature within the aforementioned range is advantageous since it does not require substantially heating or cooling the mixture from the normal ambient temperature. However, where applicable, the temperature of the mixture formed from the components of the one - component (1K) composition can be raised to a temperature above the mixing temperature and / or the application temperature using conventional means such as microwave induction.

[0148] It should be noted that in order to achieve perfection, the present invention does not exclude the preparation of epoxy adhesives in the form of "film adhesives". A prepolymer mixture of epoxy resin, hardener, and other desired components is applied as a coating on a plastic substrate, wound up, and stored at a low temperature sufficient to suppress the chemical reaction between the components. If necessary, the film adhesive is taken out of the low-temperature environment, applied to a metal or composite member, the backing is peeled off to complete the assembly, and then cured in an oven or autoclave.

[0149] The present invention will be described with reference to the following accompanying drawings.

[0150] As shown in FIG. 1a attached hereto, an adhesive structure is provided in which a layer of cured adhesive (10) is disposed between two conductive substrates (11). A layer of non-conductive material (12) can be disposed on the conductive substrate (11) to form a more complex adhesive structure as shown in FIG. 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 DC source. The positive and negative terminals of the power source (13) are shown in one fixed position, but those skilled in the art will of course recognize that the polarity of the system can be reversed.

[0151] The two conductive substrates (11) are shown in the form of layers that can be composed of, inter alia, metal films; metal sheets; metal meshes or grids; deposited metal particles; resin materials made conductive by conductive elements disposed therein; or conductive oxide layers. 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 cured adhesive (10), the effectiveness of the peeling operation may be reduced.

[0152] When a voltage is applied between the conductive substrates (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 is peelable from the substrates to be easily removed.

[0153] As depicted in FIGS. 2a and 2b, peeling occurs at the positive interface, which is the interface between the adhesive composition (10) and the conductive surface (11) that is 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.

[0154] However, it should be noted that the composition of the adhesive layer (10) can be adjusted so that peeling occurs at either the positive or negative interface, or simultaneously from both. For some embodiments, the voltage applied to both surfaces to form the anodic and cathodic interfaces causes peeling to occur simultaneously at both the anodic and cathodic adhesive / substrate interfaces. In another embodiment, when the composition does not respond to direct current at both interfaces, opposite polarities can be used to peel both substrate / adhesive interfaces simultaneously. The current can be applied in any suitable waveform, provided that the total time allowed for peeling 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.

[0155] Without intending to limit the present invention, it is considered that the peeling 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 200 V; and b) a voltage applied for 1 second to 120 minutes, for example, 1 second to 60 minutes, or 1 second to 30 minutes. When the peeling of the conductive substrate from the cured adhesive is promoted by the application of a force exerted by, for example, a weight or a spring, the potential requires only an application on the order of several seconds. In some embodiments, a potential of 5 V for 10 minutes is sufficient to have a peeling effect, while in some embodiments, a potential of 3.5 V for 30 minutes is sufficient.

[0156] 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

[0157] In the examples, the following materials were used. DER 331: Liquid epoxy resin, reaction product of epichlorohydrin and bisphenol A, available from Olin. DER 337: Intermediate epoxy equivalent semi-solid resin based on bisphenol A epoxy, available from Olin DER 337-X80: Intermediate epoxy equivalent semi-solid resin (in xylene) based on bisphenol A epoxy, available from Olin TMP: Trimethylolpropane tris(3-mercaptopropionate) (manufactured by sigma aldrich) Dyhard 100SH: Dicyandiamide, available from AlzChem Group AG 1-Methylimidazole: Available from BASF Ajicure PN-H: Epoxy amine adduct, available from Ajinomoto Cab-O-Sil 720: Fumed silica surface-treated with polydimethylsiloxane (PDMS), available from Cabot Corporation Clearstrength (registered trademark) XT100: Core-shell toughening agent (methyl methacrylate-butadiene-styrene, MBS), available from Arkema Inc. Aerosil R202: Fumed silica, available from Degussa Omyacarb 4HD: Calcium carbonate filler, available from Omya Luzenac 2: Talc, available from Rio Tinto PM182: Premix of epoxy (DER331), fumed silica, and organic acid, available from Henkel Printex L: Carbon black powder with 20% DER 331, available from Orion and Cabot EMIM-MS: 1-Ethyl-3-methylimidazolium methanesulfonate, available from TCI America Inc PEG400: Polyethylene glycol, available from SigmaAldrich Gransurf 77: PEG-10 dimethicone, available from GrantIndustries

[0158] Example 1 The preparations described in Table 1 below were produced under mixing.

[0159]

Table 1

[0160] The coated substrates in Example 1 below were aluminum (AA6016) with a thickness of 1 mm and steel with a thickness of 1.5 mm. For the tensile test, the substrates were cut into samples with dimensions of 2.5 cm × 10 cm (1'' × 4''). The tensile lap shear (TLS) test was conducted according to the test method described on page 4.

[0161] The applied one-component (1K) adhesive composition was cured in the overlapping area by applying a temperature of 100 °C for 30 minutes. Subsequently, the samples were stored in a climate chamber at 25 °C and a humidity of 20%.

[0162] After the 24-hour storage period, the tensile lap shear strength was examined both before and after applying a constant potential of 50 V to the entire adhesive layer for 20 minutes. The results are shown in Table 2 below.

[0163] [Table 2]

[0164] For an aluminum substrate (AA6016) joined with an adhesive, the lap shear strength (MPa) was examined under the following two conditions: a) A constant potential (75 V) was applied to the overlapping joint region of the sample substrate for different times including up to 120 minutes; and b) Different potentials were applied to the overlapping joint region of the sample substrate for a fixed time (30 minutes) at each applied potential. These test results are shown in the attached Figures 3a and 3b.

[0165] A stability test was conducted on the composition of Example 1. In this test, general lap shear samples were prepared and cured at 100 °C for 30 minutes. Aluminum and steel substrates were used. Then, the samples were stored in a climate chamber at 25 °C and 20% humidity.

[0166] Lap shear was measured after 1 day, 7 days, 14 days, 28 days, and 60 days. The results are shown in Table 3 below.

[0167] [Table 3]

[0168] The stability results are shown in Figure 4. Figure 4 shows the adhesion characteristics and peel effect in aluminum. The test results indicate that the compositions of the present invention have good initial adhesion characteristics and do not impair them over time. Furthermore, the compositions of the present invention have a good initial peel effect and maintain it over a long period.

[0169] Example 2 The preparation described in Table 4 below was produced under mixing.

[0170]

Table 4

[0171] The coated substrate of Example 1 below was aluminum (AA6016) with a thickness of 1.25 mm. For the tensile test, the substrate was cut into samples with dimensions of 2.5 cm × 10 cm (1'' × 4''). The tensile lap shear (TLS) test was carried out according to the test method described on page 4.

[0172] The applied one-component (1K) adhesive composition was cured in the overlapping area by applying a temperature of 180 °C for 30 minutes. Next, the joined structure was stored at room temperature for 24 hours before the initial tensile test.

[0173] For each substrate, after the 24-hour storage period, the tensile lap shear strength was examined both before and after applying a constant potential of 50 V to the entire adhesive layer for 20 minutes. The results are shown in Table 5 below.

[0174]

Table 5

[0175] A stability test was carried out on the composition of Example 2. In this test, a general lap shear sample was prepared and cured at 180 °C for 30 minutes. Substrates of aluminum (thickness 1 mm) and steel (thickness 1.5 mm) were used. Next, the samples were stored in a climate chamber at 25 °C and 20% humidity.

[0176] Lap shear was measured after 1 day, 8 days, 15 days, 29 days, and 50 days. The results are shown in Tables 6 and 7 below.

[0177]

Table 6

[0178]

Table 7

[0179] The results of the stability are shown in FIGS. 5 and 6. FIGS. 5 and 6 show the adhesion characteristics and the peeling effect in aluminum. The test results indicate that the composition of the present invention has good initial adhesion characteristics and does not impair them over time. Furthermore, the composition of the present invention has a good initial peeling effect and maintains it over a long period.

[0180] Example 3 The preparations described in Table 6 below were produced under mixing.

[0181]

Table 8

[0182] The coated substrate of Example 1 below was aluminum (AA6016) with a thickness of 1.25 mm inches. For the tensile test, the substrate was cut into samples with dimensions of 2.5 cm × 10 cm (1'' × 4''). The tensile lap shear (TLS) test was performed according to the test method described on page 4.

[0183] The applied one-component (1K) adhesive composition was cured in the overlapping area by applying a temperature of 180° C. for 30 minutes. Then, the samples were stored in a climate chamber at 25° C. and 20% humidity.

[0184] For each substrate, the tensile lap shear strength was examined both before and after applying a constant potential of 50 V for 20 minutes across the entire adhesive layer after the 24-hour storage period. The results are shown in Table 7 below.

[0185]

Table 9

[0186] Example 4 The preparation described in Table 8 below was produced under mixing.

[0187]

Table 10

[0188] The coated substrate of Example 1 below was aluminum (AA6016) with a thickness of 1.25 mm. For the tensile test, the substrate was cut into samples with dimensions of 2.5 cm × 10 cm (1'' × 4''). The tensile lap shear (TLS) test was conducted according to the test method described on page 4.

[0189] The applied one-component (1K) adhesive composition was cured in the overlapping area by applying a temperature of 100 °C for 30 minutes. Then, the samples were stored in a climate chamber at 25 °C and 20% humidity.

[0190] For each substrate, after the 24-hour storage period, the tensile lap shear strength was examined both before and after applying a constant potential of 50 V for 20 minutes across the entire adhesive layer. The results are shown in Table 9 below.

[0191]

Table 11

[0192] Example 5 The preparation described in Table 10 below was produced under mixing.

[0193]

Table 12

[0194] The coated substrate of Example 1 below was aluminum (AA6016) with a thickness of 1.25 mm. For the tensile test, the substrate was cut into samples with dimensions of 2.5 cm × 10 cm (1'' × 4''). The tensile lap shear (TLS) test was conducted according to the test method described on page 4.

[0195] The applied one - component (1K) adhesive composition was cured in the overlapping area by applying a temperature of 100°C for 30 minutes. Then, the samples were stored in a climate chamber at 25°C and 20% humidity.

[0196] For each substrate, the tensile lap - shear strength was examined both before and after applying a constant potential of 50 V for 20 minutes across the entire adhesive layer after the 24 - hour storage period. The results of Example 5a are shown in Table 11 below, and the results of Examples 5b - 5d are shown in Table 12 below.

[0197]

Table 13

[0198]

Table 14

[0199] Samples were prepared on nickel substrates, cured at 100°C for 30 minutes, and stored for a long time at 25°C and 20% relative humidity. The results are shown in Table 13 below.

[0200]

Table 15

[0201] The aging effects of Example 5a and Example 5d were investigated. Aluminum lap - shear strength (LSS) samples were prepared and stored in an oven at 140°C for a long time. The samples were tested without applying voltage and after applying voltage. The results are shown in Table 14 and Figure 7 below. It is noted that the initial strength remains unchanged and the peeling effect is kept constant.

[0202]

Table 16

[0203] Also, the aging effect of Example 5d was examined under different aging conditions (relative humidity 20%, 25 °C). Samples were prepared from aluminum AA6016 and stainless steel 1.4301 and cured at 100 °C for 30 minutes. The samples were imaged for a long time at a relative humidity of 20% and 25 °C. The results are shown in Table 15 and Figure 8 below.

[0204]

Table 17

[0205] Example 6 In this example, the effect of the non-conductive filler was investigated. A composition containing both the non-conductive filler and the electrolyte (Example 6a) was compared with a composition not containing the electrolyte (Example 6b). The details of the composition are described in Table 16 below, and the results are shown in Table 17 below.

[0206]

Table 18

[0207]

Table 19

[0208] The results are also shown in Figure 9. Example 6b, which does not contain the electrolyte, did not show a peeling effect.

[0209] In view of 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 claims.

Claims

1. a) an epoxy resin; b) a curing agent for the epoxy resin; c) an electrolyte; and d) a non-conductive filler; comprising e) a combination of a solubilizer and a strengthening agent, and f) conductive particles and being a curable and peelable one-component (1K) adhesive composition containing at least one of them, wherein, based on the total weight of the adhesive composition, 0.01 to 25% by weight of the curing agent for the b) epoxy resin, 2.0 to 25% by weight of the c) electrolyte, and 1 to 50% by weight of the d) non-conductive filler are present.

2. The curable and peelable adhesive composition according to claim 1, wherein the epoxy resin is selected from the group consisting of bisphenol A epoxy resin, bisphenol F epoxy resin, a mixture of bisphenol A epoxy resin and bisphenol F epoxy resin, and mixtures thereof, preferably the epoxy resin is bisphenol A epoxy resin.

3. The curable and peelable adhesive composition according to claim 1 or 2, wherein the epoxy resin is present in an amount of 15 to 75% by weight, preferably 20 to 65% by weight, more preferably 23 to 61% by weight of the total weight of the composition.

4. The curable and peelable adhesive composition according to any one of claims 1 to 3, wherein the curing agent comprises, or consists of, a thiol-based curing agent selected from the group consisting of tris-(3-mercaptopropionate) (TMP), pentaerythritol tetra(3-mercaptopropionate), di-pentaerythritol hexa(3-mercaptopropionate), pentaerythritol tetra(3-mercaptopropionate), tris(2-(mercaptopropionyloxy)ethyl) isocyanate and mixtures thereof, preferably the thiol-based curing agent is tris-(3-mercaptopropionate).

5. The curable and peelable adhesive composition according to any one of claims 1 to 4, wherein the curing agent comprises, or consists of, an amine-based curing agent, preferably an amine-based curing agent selected from the group consisting of alicyclic amines, aliphatic amines, dicyandiamide, polyetheramines and mixtures thereof, preferably the amine-based curing agent is selected from polyetheramines, dicyandiamide and mixtures thereof.

6. The curable and peelable adhesive composition according to any one of claims 1 to 5, wherein the curing agent is present in an amount of 0.1 to 23% by weight, more preferably 0.5 to 21% by weight, of the total weight of the composition.

7. The electrolyte is 1-ethyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium methylsulfate, 1-hexyl-3-methylimidazolium 2-(2-fluoroanilino)-pyridinate, 1-hexyl-3-methylimidazolium imide, 1-butyl-1-methyl-pyrrolidinium 2-(2-fluoroanilino)-pyridinate, 1-butyl-1-methyl-pyrrolidinium imide, trihexyl(tetradecyl)phosphonium 2-(2-fluoroanilino)-pyridinate, cyclohexyltrimethylammonium bis(trifluoromethylsulfonyl)imide, di(2-hydroxyethyl)ammonium trifluoroacetate, N,N-dimethyl(2-hydroxyethyl)ammonium octanoate, methyltrioctylammonium bis(trifluoromethylsulfonyl)imide, N-ethyl-N,N,N,N-tetramethylguanidinium trifluoromethanesulfonate, guanidinium trifluoromethanesulfonate, 1-butyl-4-methylpyridinium bromide, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-butyl-3-hydroxymethylpyridinium ethylsulfate, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, 1-butyl-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate, 3-methylimidazolium ethylsulfate, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-ethyl-methylimidazolium bromide, 1-butyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium chloride, 1-octyl-3-methylimidazolium chloride, 1-methyl-3-octylimidazolium chloride, 1-propyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, 1-butyl-2,Selected from the group consisting of 3-dimethylimidazolium hexafluorophosphate, 1-butylimidazole, 1-methylimidazolium tetrafluoroborate, tetrabutylphosphonium tris(pentafluoroethyl) trifluorophosphate, trihexyl(tetradecyl)phosphonium tetrafluoroborate, and mixtures thereof, preferably, the electrolyte is selected from 1-ethyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium methylsulfate, and mixtures thereof, the curable and peelable adhesive composition according to any one of claims 1 to 6.

8. The curable and peelable adhesive composition according to any one of claims 1 to 7, wherein the electrolyte is present in an amount of 3 to 20% by weight, more preferably 5 to 18% by weight, of the total weight of the composition.

9. The curable and peelable adhesive composition according to any one of claims 1 to 8, wherein the non-conductive filler is selected from the group consisting of calcium carbonate, calcium oxide, talc, fumed silica, silica, wollastonite, barium sulfate, and mixtures thereof.

10. The curable and peelable adhesive composition according to any one of claims 1 to 9, wherein the non-conductive filler is present in an amount of 1.5 to 48% by weight, more preferably 2 to 47%, of the total weight of the composition.

11. The curable and peelable adhesive composition according to any one of claims 1 to 10, wherein the solubilizing agent is selected from polyoxyalkylene glycol, silicone surfactant, polyhydric alcohol, and sugar, preferably, the solubilizing agent is selected from polyethylene glycol, silicone surfactant, and mixtures thereof.

12. The curable and peelable adhesive composition according to any one of claims 1 to 11, wherein the solubilizing agent is present in an amount of 1 to 15% by weight, preferably 2 to 10% by weight, more preferably 3 to 7% by weight, of the total weight of the composition.

13. The curable and peelable adhesive composition according to any one of claims 1 to 12, wherein the reinforcing agent is present in an amount of 5 to 40% by weight, preferably 10 to 25% by weight, more preferably 12 to 16% by weight, of the total weight of the composition.

14. The curable and peelable adhesive composition according to any one of claims 1 to 13, comprising conductive particles selected from the group consisting of silver, carbon black, and mixtures thereof, preferably, the conductive particles are carbon black.

15. The curable and peelable adhesive composition according to claim 14, wherein the conductive particles are present in an amount of 0.1 to 5% by weight, preferably 0.5 to 4% by weight, more preferably 1 to 3% by weight, of the total weight of the composition.

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

17. 1) A step of applying a voltage to the entire both surfaces to form an anode interface and a cathode interface, and 2) A step of peeling the both surfaces A method for peeling the adhesive structure according to claim 16, comprising:

18. The method according to claim 17, wherein the voltage applied in step 1) is 0.5 to 200 V.

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