Two-component epoxy structural adhesive composition

Abstract

The present invention provides a two-part epoxy structural adhesive composition comprising a first part and a second part. The first part comprises i) a first aromatic difunctional epoxy resin having an epoxide equivalent weight (EEW) of less than 400 g / eq, ii) a second aromatic difunctional epoxy resin having an epoxide equivalent weight of 400 g / eq to 3000 g / eq, and iii) a shell-core toughening agent. The second part comprises I) a non-aromatic polyether amidoamine and II) a cycloaliphatic amine. The present invention also provides a method for bonding substrates using the adhesive composition, an article bonded with a cured product of the adhesive composition, and a use of the composition in assembling an article.

Description

Technical Field

[0001] The present invention relates to a two-component epoxy-based structural adhesive composition comprising a first part and a second part, wherein the first part comprises i) a first aromatic difunctional epoxy resin having an epoxy equivalent weight (EEW) of less than 400 g / eq, ii) a second aromatic difunctional epoxy resin having an epoxy equivalent weight of 400 g / eq to 3000 g / eq, and iii) a shell-core strengthening agent, and the second part comprises I) a non-aromatic polyether amide amine and II) an alicyclic amine. Further, the present invention also relates to a method for bonding a substrate using the adhesive composition, an article bonded with a cured product of the adhesive composition, and the use of the composition in the assembly of an article.

Background Art

[0002] Structural adhesives are used in a variety of applications such as general industrial applications and high-performance applications in the automotive and aerospace industries. Typically, structural adhesives can be used to join substrates or components such as wood, metal, coated metal, plastic, filled plastic, fiberglass, screws, bolts, nails, staples, rivets, and parts used in automobiles.

[0003] Epoxy resin-based structural adhesives are an important class among structural adhesives. Usually, epoxy-based structural adhesives are classified into "one-component" or "two-component" formulations. In one-component formulations, all components of the formulation including the epoxy component and the curing agent are formed into a single blend. Curing of one-component adhesives occurs, in most cases, by exposing the formulation to high temperatures. Since all the reactive components are present in one-component formulations, the adhesives tend to cure early, making it difficult to apply them to substrates. In extreme cases, the product becomes completely unusable. There is no problem of early curing in two-component structural adhesives.

[0004] Conventional epoxy-based structural adhesives usually have good shear bond strength, but due to their hard and brittle structure, their peel bond strength is inferior.

[0005] Chinese Patent Application Publication No. 101818037 discloses a two-component epoxy structural adhesive composition and a method for producing the same, proposing to improve shear adhesive strength by incorporating a CTBN-modified bisphenol A type epoxy resin and / or a shell-core polymer-reinforced bisphenol A epoxy resin as the epoxy component and using a combination of specific polyamides and specific polyetheramines as curing agents, thereby achieving a maximum shear strength of 22 MPa and a maximum T peel strength of 6.5 N / mm, although there is still room for improvement. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Chinese Patent Application Publication No. 101818037 Specification [Overview of the project] [Problems that the invention aims to solve]

[0007] However, there remains a need to provide structural adhesives that possess both high shear strength and high peel strength. [Means for solving the problem]

[0008] In one aspect of the present invention, a two-component epoxy structural adhesive composition is provided that can achieve high shear strength and high peel strength, that is, high peel strength without impairing shear strength.

[0009] Specifically, the two-component epoxy structural adhesive composition of the present invention comprises a first part and a second part, the first part comprising i) a first aromatic bifunctional epoxy resin having an epoxide equivalent of less than 400 g / eq, ii) a second aromatic bifunctional epoxy resin having an epoxide equivalent of 400 g / eq to 3000 g / eq, and iii) a shell-core reinforcing agent, and the second part comprising I) a non-aromatic polyetheramide amine and II) an alicyclic amine.

[0010] Another aspect of the present invention provides a method for bonding substrates using the adhesive composition of the present invention.

[0011] In yet another aspect of the present invention, an article comprising a cured product of the adhesive composition of the present invention is provided.

[0012] In yet another aspect of the present invention, the use of the composition of the present invention in the assembly of articles, vehicle frame structures, buildings, or household and industrial products is provided. [Effects of the Invention]

[0013] The two-component epoxy structural adhesive composition of the present invention can provide an adhesive that possesses both high shear strength and high peel strength. [Modes for carrying out the invention]

[0014] Those skilled in the art should understand that this discussion is for illustrative purposes only and is not intended to limit the broader aspects of the invention. Each of the aspects described herein can be combined with any other aspect unless expressly indicated otherwise. In particular, any one feature indicated as preferred or advantageous can be combined with one or more other features indicated as preferred or advantageous.

[0015] Unless otherwise specified, terms used in the context of this invention shall be interpreted according to the following definitions.

[0016] Unless otherwise specified, all weight percentages (wt.%) or weight percentages (% by weight) cited herein are weight percentages.

[0017] Unless otherwise specified, the terms "a," "an," and "the" as used herein include both singular and plural nouns.

[0018] As used herein, the terms "comprising" and "comprises" are synonymous with "including", "include" or "containing", "contains", and are inclusive or open-ended and do not exclude additional, unrecited members, elements or process steps.

[0019] As used herein, the term "consisting essentially of" means that the recited components constitute at least 70% by weight, at least 80% by weight, at least 85% by weight, or at least 90% by weight of the body of the composition, such as the composition.

[0020] As used herein, the term "consisting of" is closed-ended and excludes additional, intentionally added members, elements or process steps.

[0021] As used herein, the terms "at least one" or "one or more" used to define a component mean the type of component and not the absolute number of molecules.

[0022] As used herein, terms such as "about" and "around" used in connection with a numerical value mean ±10% of the numerical value, preferably ±5%. All numerical values herein should be construed as being modified by the term "about".

[0023] Unless otherwise specified, the recitation of numerical endpoints includes all numerical values and fractions subsumed within the respective ranges as well as the recited endpoints.

[0024] All documents cited herein are hereby incorporated by reference in their entirety.

[0025] Unless otherwise defined, all terms used in this invention, including terminology and scientific terms, have the meanings generally understood by those skilled in the art to which this invention belongs.

[0026] The epoxide equivalent (EEW) values ​​described herein are measured in accordance with ASTM D1652.

[0027] The amine hydrogen equivalent (AHEW) as described herein has the conventional meaning in the art, that is, it is calculated by dividing the molecular weight by the number of active hydrogens.

[0028] The two-component epoxy-based structural adhesive composition of the present invention will be described in detail below.

[0029] This two-component epoxy structural adhesive composition, i) A first aromatic bifunctional epoxy resin having an epoxide equivalent of less than 400 g / eq, preferably 100 to 300 g / eq, for example 110 to 250 g / eq, ii) A second aromatic bifunctional epoxy resin having an epoxide equivalent of 400 g / eq to 3000 g / eq, preferably 410 to 2000 g / eq, for example 420 to 1000 g / eq, 430 to 600 g / eq, and iii) Shell-core strengthening agent The first part, and I) Non-aromatic polyetheramidoamines, II) Alicyclic amines Includes the second part which includes the second part.

[0030] This adhesive composition may consist of the first part and the second part described above.

[0031] <First part> As used herein, the term “Part One” is not intended to define an order for this part, but simply to name it so as to distinguish it from other parts, such as Part Two. That is, Part One and Part Two are not provided in that order; on the contrary, they can be provided in any order. Similarly, the term “Part Two” is not intended to define an order for this part, but simply to name it so as to distinguish it from Part One. Alternatively, Part One may be referred to as the “Epoxy Part” and Part Two as the “Curing Agent Part.”

[0032] The first part comprises i) a first aromatic bifunctional epoxy resin having an epoxide equivalent of less than 400 g / eq, ii) a second aromatic bifunctional epoxy resin having an epoxide equivalent of 400 g / eq to 3000 g / eq, and iii) a shell-core reinforcing agent.

[0033] The first part contains a first aromatic bifunctional epoxy resin, a second aromatic bifunctional epoxy resin, and a shell-core reinforcing agent as essential components, wherein the first aromatic bifunctional epoxy resin has an epoxide equivalent of less than 400 g / eq, preferably 100 to 300 g / eq, for example 110 to 250 g / eq, and the second aromatic bifunctional epoxy resin has an epoxide equivalent of 400 g / eq to 3000 g / eq, preferably 410 to 2000 g / eq, for example 410 to 1500 g / eq, 420 to 1000 g / eq, 430 to 800 g / eq, 430 to 600 g / eq.

[0034] As used herein, the first and second aromatic bifunctional epoxy resins independently mean epoxy resins comprising two epoxy groups and containing at least one aromatic unit in the molecule (e.g., in the backbone or, if present, in the side chains, or both in the backbone and side chains). Typically, the first and second aromatic bifunctional epoxy resins contain two epoxy groups, preferably at the terminal positions of the resin backbone or, if present, the side chains, for example, derived from a glycidyl ether.

[0035] Suitable first and second aromatic bifunctional epoxy resins used herein include aromatic glycidyl ethers, such as those that can be prepared by reacting a divalent phenol (i.e., a phenol having another functional group having a reactive proton, such as a hydroxyl group) with an excess of epichlorohydrin. Examples of useful divalent phenols include resorcinol, catechol, hydroquinone, and bisphenol.

[0036] Preferably, the first and second aromatic bifunctional epoxy resins used herein are independently selected from bisphenol A epoxy resin (derived from bisphenol A and epichlorohydrin, or a reaction product of bisphenol A and epichlorohydrin), bisphenol F epoxy resin (derived from bisphenol F and epichlorohydrin, or a reaction product of bisphenol F and epichlorohydrin), bisphenol S epoxy resin (derived from bisphenol S and epichlorohydrin, or a reaction product of bisphenol S and epichlorohydrin), phenol novolac epoxy resin (obtained by reacting phenol with formaldehyde, and then with epichlorohydrin), cresol novolac epoxy resin (obtained by reacting cresol with formaldehyde, and then with epichlorohydrin), tetrabromosfinol A epoxy resin, tetrabromobisfinol F epoxy resin, and combinations thereof.

[0037] While we do not wish to be bound by theory, the use of a bifunctional epoxy resin is considered useful for achieving the beneficial technical effects of the present invention, and as shown in the following examples, the inclusion of a highly functional epoxy resin, such as a tetrafunctional epoxy resin, prevents the achievement of the desired technical effects. Therefore, it is even more preferable that the adhesive composition of the present invention does not contain a trifunctional epoxy resin and / or a tetrafunctional epoxy resin and / or a highly functional epoxy resin.

[0038] While we do not wish to be bound by theory, it is considered useful to use the two aromatic bifunctional epoxy resins described above in combination to achieve the beneficial technical effects of the present invention. The first and second aromatic bifunctional epoxy resins used herein may have the same or different constituent units, as long as the two epoxy resins have the EEW defined above. On the other hand, as shown in the following examples, the desired effects of the present invention cannot be achieved with only one type of aromatic epoxy resin.

[0039] While we do not wish to be bound by theory, it is considered useful to use the second aromatic bifunctional epoxy resin having an EEW of 400-3000 g / eq to achieve the beneficial technical effects of the present invention, and as shown in the following examples, the technical effects will be inferior at EEW values ​​outside this range.

[0040] Suitable commercially available first aromatic bifunctional epoxy resins include, for example, "EPON828" and "EPON862" from Hexion Specialty Chemicals; "DER-331," "DER-332," and "DER-334" from Dow Chemical; and diglycidyl ethers of bisphenol A or bisphenol F, available under trade names E51 and E44.

[0041] A suitable commercially available second aromatic bifunctional epoxy resin is, for example, diglycidyl ether of bisphenol A or bisphenol F, which is available from Dow Chemical under the trade name "DER671".

[0042] The adhesive composition may include one or more of the first aromatic bifunctional epoxy resins and one or more of the second aromatic functional epoxy resins.

[0043] Preferably, the first aromatic bifunctional epoxy resin is included in the first part in amounts of 30% to 75% by weight, preferably 35% to 70% by weight, based on the total weight of the first part, for example, 37%, 39%, 40%, 42%, 45%, 50%, 55%, 57%, 60%, 62%, 65%, 67%, 68%, etc.

[0044] Preferably, the second aromatic bifunctional epoxy resin is included in the first part in an amount of 1% to 10% by weight, based on the total weight of the first part, for example, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight, etc.

[0045] As an epoxy resin component, the first part may contain only the first and second aromatic bifunctional epoxy resins described above. Alternatively, in addition to the first and second aromatic bifunctional epoxy resins, the first part may optionally further contain small amounts of other bifunctional epoxy resins different from the first and second aromatic bifunctional epoxy resins, for example, in amounts of less than 3% by weight or less than 1% by weight relative to the first part, provided that the other bifunctional epoxy resins do not impair the beneficial effects of the present invention.

[0046] The shell-core reinforcing agent used in this invention may be a core-shell polymer (sometimes called core-shell rubber). A core-shell polymer means a polymer having a core-shell structure. Core-shell polymers are prepared by providing a core polymer grafted with a shell-forming polymer.

[0047] Typically, the core comprises or consists of a polymer selected from the group consisting of butadiene polymers or copolymers, acrylonitrile polymers or copolymers, acrylate polymers or copolymers, and combinations thereof. The polymer or copolymer may or may not be crosslinked. In some embodiments, the core polymer is crosslinked.

[0048] One or more shell polymers are grafted onto the core. The shell polymer can be selected from the group consisting of styrene polymers or copolymers, methacrylate polymers or copolymers, acrylonitrile polymers or copolymers, or combinations thereof. The resulting shell can be further functionalized with epoxy or acidic groups. Shell functionalization can be achieved, for example, by copolymerization with glycidyl methacrylate or acrylic acid. In particular, the shell may contain an acetoacetoxy moiety, in which case the amount of acetoacetoxy-functionalized polymer may be reduced or completely replaced by an acetoacetoxy-functionalized core / shell polymer.

[0049] The shell of a suitable core-shell polymer may include, for example, a polyacrylate polymer or copolymer shell such as a polymethyl methacrylate shell. The polyacrylate shell, such as a polymethyl methacrylate shell, does not need to be crosslinked.

[0050] The core of a suitable core-shell polymer may include a butadiene polymer or copolymer, a styrene polymer or copolymer, or a butadiene-styrene copolymer. The polymer or copolymer constituting the core, such as a butadiene-styrene core, may be crosslinked.

[0051] Examples of commercially available core-shell polymers include those from Kaneka Corporation, such as the "KANE ACE" series, specifically the "KANE ACE MX154" product.

[0052] Preferably, the shell-core reinforcing agent can be included in the first part in an amount of 5% to 35% by weight, preferably 10% to 30% by weight, based on the total weight of the first part, for example, 12% by weight, 15% by weight, 18% by weight, 20% by weight, 22% by weight, 25% by weight, 27% by weight, etc.

[0053] <Second part> The second part of the present invention comprises a non-aromatic polyetheramidoamine and an alicyclic amine as essential components.

[0054] As used herein, the term "non-aromatic" means that the molecule does not contain any aromatic groups.

[0055] The non-aromatic polyetheramidoamines used herein contain an ether structure, an amide structure, and one or more amino groups (-NH2) within the molecule.

[0056] Preferably, the above ether structure may include the unit -(RO-R')-, where R or R' is independently C1-C 10 These are linear or branched alkylenes, such as methylene, ethylene, propylene, butylene, pentylene, hexylene, and their isomers. Alternatively, the oxygen atom in the ether structure may be directly bonded to the nitrogen atom of the amino group, particularly the terminal amino group.

[0057] Preferably, the amide structure may contain a -C(=O)-NR''- unit, where R'' is H or an organic group, such as an alkyl or alkenyl group, which may be the ether structure described above. Preferably, the amide structure constitutes 50% by weight or more of the non-aromatic polyetheramidoamine.

[0058] Preferably, non-aromatic polyetheramidoamines useful herein have an amine hydrogen equivalent (AHEW) of 150 g / eq or more, preferably 180 g / eq or more, for example, 190-300 g / eq, 200-270 g / eq, etc.

[0059] A commercially available example of a non-aromatic polyetheramidoamine is Ancamide® 910 from Evonik.

[0060] The second part further contains an alicyclic amine as an essential component. In the present invention, alicyclic amines that have been conventionally used in the art can be used as curing agents. Preferably, the alicyclic amine has at least one alicyclic group, such as a 5-membered ring and a 6-membered ring, preferably, the alicyclic amine has at least two -NH2 groups, and preferably, the alicyclic ring of the alicyclic amine is a carbon ring that is not interrupted by a heteroatom.

[0061] Preferably, the alicyclic amines useful herein have an amine hydrogen equivalent (AHEW) of 40 g / eq or more, preferably 45 g / eq or more, for example, 50 g / eq or more.

[0062] For example, useful alicyclic amines in this specification can be selected from 4,4'-diaminodicyclohexylmethane (PACM or HMDA), 4,4'-methylenebis(2-methylcyclohexaneamine) (DMDC), and isophorone diamines.

[0063] While we do not wish to be bound by theory, the presence of alicyclic groups in amine curing agents is useful in achieving the beneficial effects of the present invention, and it is considered important to use the above-mentioned polyetheramide amine and alicyclic amine in combination in order to achieve the desired effects of the present invention.

[0064] The second part may contain one or more of the above-mentioned polyetheramide amines and one or more of the above-mentioned alicyclic amines.

[0065] Preferably, the polyetheramidoamine is included in the second part in an amount of 30-80% by weight, preferably 32-70% by weight, 35-65% by weight, 40-63% by weight, for example, 45% by weight, 50% by weight, 55% by weight, 60% by weight, etc., based on the total weight of the second part.

[0066] Preferably, the alicyclic amine is included in the second part in an amount of 10-45% by weight, preferably 15-43% by weight, 20-40% by weight, based on the total weight of the second part, for example, 18% by weight, 23% by weight, 25% by weight, 30% by weight, 33% by weight, 35% by weight, etc.

[0067] In addition to the polyetheramidoamines and alicyclic amines described above, the second part may preferably include additional non-aromatic amines having an AHEW of 35 g / eq or more, preferably 40 g / eq or more, for example, 50 g / eq or more.

[0068] For example, the additional non-aromatic amines useful herein may be polyetheramines. Non-aromatic polyetheramines used herein contain an ether structure and at least two -NH2 groups. Preferably, the ether structure is of the formula: -(RO) n - can be expressed as, where each R is independent of each other, C1-C 10 The alkylenes are linear or branched alkylenes such as methylene, ethylene, propylene, butylene, pentylene, hexylene and their isomers, where n is in the range of 1 to 50, preferably 1 to 20, more preferably 1 to 10. In a preferred embodiment, the non-aromatic polyetheramine is derived from propylene oxide or ethylene oxide or their isomers, for example, H2NCH(CH3)CH2-(OCH2CH(CH3)) n It has the structure -NH2, where n is in the range of 1 to 100, for example, 1 to 50, or 1 to 20.

[0069] Commercially available additional non-aromatic amines include Huntsman's JEFFMINE® D series, such as D-230 and D-400, as well as the JEFFMINE® ED series, JEFFMINE® T series, and Evonik's ANCAMINE® 2914UF.

[0070] In a preferred embodiment, one or more of the additional non-aromatic amines may be included in the second part in amounts of 1% to 15% by weight, for example, 2% by weight, 3% by weight, 5% by weight, 7% by weight, 9% by weight, 10% by weight, 12% by weight, etc., based on the total weight of the second part.

[0071] The second part may contain, as a curing agent, the above-mentioned non-aromatic polyetheramidoamine and alicyclic amine and optionally additional non-aromatic amines, or may essentially consist of, or consist of, non-aromatic polyetheramidoamine and alicyclic amine and optionally additional non-aromatic amines.

[0072] On the other hand, it is preferable that the second part of the present invention does not contain an amine curing agent with an AHEW of less than 35 g / eq.

[0073] <Other additives> The adhesive composition of the present invention may contain one or more additives conventionally used in the art, such as fillers, reactive diluents, pigments, coupling agents, surfactants, and catalysts. The additives can perform functions such as modifying the rheology of the adhesive in a desired manner, promoting cohesiveness, reducing the overall cost per unit weight, and absorbing moisture and oil from the adhesive or the substrate to which it is applied.

[0074] Additives may be included in the first and / or second parts, provided they do not react with the components of the first and / or second parts in which they are contained. For example, fillers or pigments or surfactants may be included in the first part only, the second part only, or both the first and second parts.

[0075] <Filler> The optional addition of fillers to structural adhesives can, for example, enhance adhesion, improve corrosion resistance, control the rheological properties of the adhesive, and / or reduce shrinkage during curing.

[0076] Examples of these fillers include, but are not limited to, calcium carbonate, calcium oxide, talc, carbon black, textile fibers, glass particles or fibers, aramid pulp, boron fibers, carbon fibers, mineral silicates, mica, powdered quartz, hydrated aluminum oxide, bentonite, wollastonite, kaolin, fumed silica, precipitated silica, amorphous silica, silica aerogel, metal powders such as aluminum powder and iron powder, calcium silicate, phosphates, molybdates, trihydrated alumina, hollow glass microspheres, and polymer microspheres.

[0077] Examples of commercially available fillers include those sold by Cabot under the trademark name Carbosil (registered trademark), such as Carbosil TS 720 and Carbosil M5, as well as BYK410 from BYK-Chemie GmbH and Talc DH 600B from Yingkou Dahai talc mining.

[0078] The filler may be included in the structural adhesive of the present invention in an amount of 1% to 20% by weight, preferably 2% to 15% by weight, based on the total weight of the adhesive composition, for example, 3% by weight, 4% by weight, 5% by weight, 7% by weight, 9% by weight, 10% by weight, 12% by weight, etc.

[0079] <Reactive Diluent> A reactive diluent may be optionally added to control the flow properties of the adhesive composition. A suitable diluent may have at least one reactive terminal portion. Examples of reactive terminal portions include glycidyl ethers.

[0080] Suitable diluents include, but are not limited to, aliphatic di / triglycidyl ethers and aromatic di / triglycidyl ethers, such as resorcinol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, neopentyl glycol diglycidyl ether, and trimethylolpropane triglycidyl ether.

[0081] Examples of commercially available reactive diluents include Heloxy® Modifier 68 and Heloxy® Modifier 48, both available from Hexion Specialty Chemicals.

[0082] The reactive diluent may be included in the first part in an amount of 1% to 25% by weight, preferably 2% to 20% by weight, based on the total weight of the first part, for example, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight, 10% by weight, 11% by weight, 12% by weight, 15% by weight, 17% by weight, etc.

[0083] <Coloring agent> The structural adhesive composition of the present invention may optionally contain colorants that have been conventionally used in the art. Examples of colorants include, but are not limited to, inorganic or organic colorants such as ferric oxide, brick powder, carbon black, titanium dioxide, bromothymol blue, brilliant blue, and phenothalin.

[0084] <Coupling agent> A coupling agent conventionally used in the art may be optionally included in the structural adhesive composition of the present invention, preferably in the first part of the composition. Examples of coupling agents include silane coupling agents. Examples of commercially available coupling agents include Momentive's Silquest A 187 and CoatOSil MP 200. <Surfactants>

[0085] Structural adhesives may optionally contain surfactants to assist in oil displacement on the substrate. Any surfactant that dissolves in the adhesive formulation can be used, including ionic surfactants, anionic surfactants, nonionic surfactants, and zwitterionic surfactants. Exemplary surfactants include tripropylene glycol monomethyl ether and polyethylene sorbitol.

[0086] <Catalyst> The structural adhesive of the present invention may optionally contain a catalytic amount of a metal salt catalyst. Suitable catalysts usable in this composition are Group I metals (e.g., lithium), Group II metals (e.g., calcium and magnesium), or lanthanide salts (e.g., lanthanum), where the anion is selected from nitrates, iodides, thiocyanates, triflates, alkoxides, perchlorates, and sulfonates. Exemplary metal salts include lanthanum nitrate, triflatlantane, lithium iodide, lithium nitrate, calcium nitrate, and their corresponding hydrates.

[0087] <Preparation of structural adhesives> The first part is prepared by mixing all the components of the first part together and heating, if applicable. The second part is prepared by mixing all the components of the second part together. The first and second parts are stored separately before use.

[0088] The structural adhesive is prepared by mixing the first and second parts of the present invention immediately before use. The mixing can be done manually or by any conventional means at room temperature or high temperature to form a uniform curable composition. The first and second parts can be mixed in a weight ratio of 2:1 or 1:1, in particular, in the range of 10:1 to 1:5, for example, 5:1 to 1:3, or 3:1 to 1:1.

[0089] Preferably, the epoxy groups of the first part and the active hydrogen of the second part are mixed with the second part so that they are used in a molar ratio of 0.5:1 to 3:1, for example 2:1, and especially about 1:1.

[0090] Curing is preferably carried out at room temperature (RT, approximately 25°C), but can also be carried out at high temperatures such as 80°C or below, or 60°C or below.

[0091] <Adhering substrates using an adhesive composition> Another object of the present invention is to provide a method for bonding substrates using the adhesive composition of the present invention, the method To provide a first substrate, Mix the first part and the second part immediately before use to form a mixture; Apply the mixture to the first substrate; A second substrate is bonded to the side of the first substrate to which the mixture has been applied, wherein the mixture may optionally be applied to the second substrate; and The mixture is cured while being heated as needed. Includes.

[0092] The adhesive composition of this application can be applied between two substrates and cured to form an adhesive joint between them. The adhesive composition can be used to strengthen or completely remove welds or mechanical fasteners. Suitable substrates to which the adhesive of this invention can be applied include metals (e.g., steel, stainless steel, carbon steel, iron, copper, aluminum, zinc, etc., and their alloys), carbon fibers, glass fibers, glass, wood, plastics, woven materials, nonwoven materials, and mixtures thereof. In some embodiments, at least one of the substrates is metal. In other embodiments, both substrates are metal.

[0093] It may be preferable to clean the surface of the substrate before applying the structural adhesive. In the bonding area, the adhesive can be applied as a liquid, paste, or semi-solid, and can be applied in the form of continuous beads, stripes, or any other geometric shape that can be adapted to form a useful bond.

[0094] The adhesive composition of the present invention can be used as a structural adhesive in the assembly of vehicles, such as ships, aircraft, or motorcraft vehicles such as automobiles, motorcycles, or bicycles. Furthermore, the adhesive composition of the present invention can be used in vehicle frame structures, buildings, or household and industrial products. [Examples]

[0095] The present invention will be described by the following examples. The following examples are intended to assist those skilled in the art in better understanding and implementing the present invention. The scope of the present invention is not limited by the examples, but is defined by the appended claims. All parts and percentages are based on weight unless otherwise specified.

[0096]

Table 1

[0097] <Lap Shear Strength Test> The lap shear strength was tested in accordance with ASTM D1002, titled "Standard Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesive Metal Specimens by Tensile Loading (Metal-to-Metal)", and the test specimens were prepared in accordance with ASTM D1002. Carbon steel was used as the substrate, and the thickness of the applied adhesive was approximately 0.2 mm.

[0098] <T-Peel Strength Test> The T-peel strength was tested in accordance with ASTM D 1876, titled "Standard Test Method for Peel Resistance of Adhesives (T-Peel Test)", and the test specimens were prepared in accordance with ASTM D 1876. Carbon steel was used as the substrate, and the thickness of the applied adhesive was approximately 0.2 mm.

[0099] <Examples and Comparative Examples> Adhesive formulations were prepared with the components shown in Tables 1 to 3 below and tested according to the above methods.

[0100] The first part of the adhesive was prepared by mixing all the components of the first part by stirring, then applying a vacuum for degassing to obtain a degassed mixture as the first part, and then storing it in a container.

[0101] The second part of the adhesive was prepared by mixing all the components of the second part by stirring, then applying a vacuum for degassing to obtain a degassed mixture as the second part, and then storing it in a different container from the first part.

[0102] When applying the adhesive, the first and second portions were extruded from the container and passed together in a static mixer in a specific ratio, and the formed adhesive was applied to the substrate.

[0103] [Table 2]

[0104] [Table 3]

[0105] [Table 4]

[0106] In the present invention, the condition is met if the tested T peel strength is 180 N / 25 mm or higher, and 190 N / 25 mm or higher is desirable. On the other hand, it is desirable if the tested lap shear strength exceeds 20 MPa.

[0107] While several preferred embodiments have been described, many modifications and variations are possible based on the teachings above. Therefore, it should be understood that the present invention may be implemented in ways other than those specifically described without departing from the scope of the appended claims. Preferred embodiments of the present invention include the following: [1]i) A first aromatic bifunctional epoxy resin having an epoxide equivalent of less than 400 g / eq, preferably 100 to 300 g / eq, for example, 110 to 250 g / eq. ii) A second aromatic bifunctional epoxy resin having an epoxide equivalent of 400 g / eq to 3000 g / eq, preferably 410 to 2000 g / eq, for example 420 to 1000 g / eq, 430 to 600 g / eq, and iii) Shell-core strengthening agent The first part, including; and I) Non-aromatic polyetheramidoamines, II) Alicyclic amines A two-component epoxy structural adhesive composition comprising a second part containing [a specific component]. [2] The composition according to [1], wherein the first aromatic bifunctional epoxy resin and the second aromatic bifunctional epoxy resin are independently selected from bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, tetrabromobisphenol A epoxy resin, tetrabromobisphenol F epoxy resin, and combinations thereof. [3] The composition according to [1] or [2], wherein the first aromatic bifunctional epoxy resin is included in the first part in an amount of 30% to 75% by weight, preferably 35% to 70% by weight, based on the total weight of the first part. [4] The composition according to any one of [1] to [3], wherein the second aromatic bifunctional epoxy resin is included in the first part in an amount of 1% to 10% by weight, preferably 2% to 9% by weight, based on the total weight of the first part. [5] The composition according to any one of [1] to [4], wherein the shell-core reinforcing agent is included in the first part in an amount of 5% to 35% by weight, preferably 10% to 30% by weight, based on the total weight of the first part. [6] The composition according to any one of [1] to [5], wherein the non-aromatic polyetheramidoamine has an amine hydrogen equivalent of 150 g / eq or more, preferably 180 g / eq or more, for example 190 to 300 g / eq or 200 to 270 g / eq. [7] The composition according to any one of [1] to [6], wherein the alicyclic amine has an amine hydrogen equivalent of 40 g / eq or more, preferably 45 g / eq or more, for example 50 g / eq or more. [8] The alicyclic amine is selected from 4,4'-diaminodicyclohexylmethane (PACM), 4,4'-methylenebis(2-methylcyclohexaneamine) (DMDC), and isophoronediamine, and is the composition according to any one of [1] to [7]. [9] The composition according to any one of [1] to [8], wherein the second portion further comprises an additional non-aromatic amine having an amine hydrogen equivalent of 35 g / eq or more, preferably 40 g / eq or more, for example 50 g / eq or more, and the additional non-aromatic amine curing agent is preferably selected from aliphatic polyetheramines.

[10] The composition according to any one of [1] to [9], wherein the non-aromatic polyetheramidoamine comprises an ether structure, an amide structure and one or more amino groups, and preferably the amide structure constitutes 50% by weight or more of the non-aromatic polyetheramidoamine.

[11] The composition according to any one of [1] to

[10] , wherein the weight ratio of the first part to the second part is in the range of 10:1 to 1:5, for example, in the range of 5:1 to 1:3, or in the range of 3:1 to 1:1, in particular 2:1 or 1:1.

[12] The composition according to any one of [1] to

[11] , wherein the molar ratio of the epoxy group of the first part to the active hydrogen of the second part is in the range of 0.5:1 to 3:1, for example 2:1, and in particular about 1:1.

[13] The composition according to any one of [1] to

[12] , wherein the polyetheramidoamine is contained in the second part in an amount of 30 to 80% by weight, preferably 32 to 70% by weight, 35 to 65% by weight, or 40 to 63% by weight, based on the total weight of the second part.

[14] The composition according to any one of [1] to

[13] , wherein the alicyclic amine is contained in the second part in an amount of 10 to 45% by weight, preferably 15 to 43% by weight, or 20 to 40% by weight, based on the total weight of the second part.

[15] The composition according to any one of [9] to

[14] , wherein the additional non-aromatic amine curing agent is included in the second part in an amount of 1% to 15% by weight, preferably 2% to 10% by weight, based on the total weight of the second part.

[16] A composition according to any one of [1] to

[15] , further comprising one or more additives selected from fillers, reactive diluents, pigments, coupling agents, surfactants, and catalysts.

[17] To provide a first substrate; Mixing the first part and the second part as defined in any one of [1] to

[18] immediately before use to form a mixture; Apply the mixture to the first substrate; A second substrate is bonded to the side of the first substrate to which the mixture has been applied, wherein the mixture may optionally be applied to the second substrate; and The mixture is cured while being heated as needed. A method for bonding substrates, including [the specified element].

[18] The method according to

[17] , wherein the first substrate and the second substrate are independently selected from metals such as steel, stainless steel, carbon steel, iron, copper, aluminum, zinc, and alloys thereof; carbon fiber; glass fiber; glass; wood; plastic; woven material; nonwoven material; and mixtures thereof. An article comprising a cured product of any one of the compositions described in

[19] [1] to

[16] , preferably the article being selected from ships, aircraft, or motorcraft vehicles such as automobiles, motorbikes or bicycles. Use of any composition described in any one of paragraphs

[20] [1] to

[16] in the assembly of ships, aircraft, or motorcraft vehicles such as automobiles, motorbikes or bicycles, in body frame structures, buildings, or in household and industrial products.

Claims

1. i) A first aromatic bifunctional epoxy resin having an epoxide equivalent of less than 400 g / eq, ii) A second aromatic bifunctional epoxy resin having an epoxide equivalent of 400 g / eq to 3000 g / eq, and iii) Shell-core strengthening agent The first part contains an epoxy resin having a functional value of 3 or more, and I) Non-aromatic polyetheramidoamines, and II) Alicyclic amines The second part contains an amine hydrogen equivalent of less than 35 g / eq and does not contain an amine curing agent. A two-component epoxy structural adhesive composition containing [the specified ingredient].

2. The composition according to claim 1, wherein the first aromatic bifunctional epoxy resin and the second aromatic bifunctional epoxy resin are independently selected from bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, tetrabromobisphenol A epoxy resin, tetrabromobisphenol F epoxy resin, and combinations thereof.

3. The composition according to claim 1 or 2, wherein the first aromatic bifunctional epoxy resin is included in the first part in an amount of 30% to 75% by weight, based on the total weight of the first part.

4. The composition according to any one of claims 1 to 3, wherein the second aromatic bifunctional epoxy resin is included in the first part in an amount of 1% to 10% by weight, based on the total weight of the first part.

5. The composition according to any one of claims 1 to 4, wherein the shell-core reinforcing agent is contained in the first part in an amount of 5% to 35% by weight, based on the total weight of the first part.

6. The composition according to any one of claims 1 to 5, wherein the non-aromatic polyetheramide amine has an amine hydrogen equivalent of 150 g / eq or more.

7. The composition according to any one of claims 1 to 6, wherein the alicyclic amine has an amine hydrogen equivalent of 40 g / eq or more.

8. The composition according to any one of claims 1 to 7, wherein the alicyclic amine is selected from 4,4'-diaminodicyclohexylmethane (PACM), 4,4'-methylenebis(2-methylcyclohexaneamine) (DMDC), and isophoronediamine.

9. The composition according to any one of claims 1 to 8, further comprising an additional non-aromatic amine having an amine hydrogen equivalent of 35 g / eq or more in the second part.

10. The composition according to claim 9, wherein the additional non-aromatic amine curing agent is included in the second part in an amount of 1% to 15% by weight, based on the total weight of the second part.

11. The composition according to any one of claims 1 to 10, wherein the non-aromatic polyetheramidoamine comprises an ether structure, an amide structure, and one or more amino groups.

12. The composition according to any one of claims 1 to 11, wherein the weight ratio of the first part to the second part is in the range of 10:1 to 1:

5.

13. The composition according to any one of claims 1 to 12, wherein the molar ratio of the epoxy group of the first part to the active hydrogen of the second part is in the range of 0.5:1 to 3:

1.

14. The composition according to any one of claims 1 to 13, wherein the non-aromatic polyetheramidoamine is contained in the second part in an amount of 30 to 80% by weight, based on the total weight of the second part.

15. The composition according to any one of claims 1 to 14, wherein the alicyclic amine is contained in the second part in an amount of 10 to 45% by weight, based on the total weight of the second part.

16. The composition according to any one of claims 1 to 15, further comprising one or more additives selected from fillers, reactive diluents, pigments, coupling agents, surfactants, and catalysts.

17. To provide a first base material; Mixing the first portion and the second portion as defined in any one of claims 1 to 16 immediately before use to form a mixture; Apply the mixture to the first substrate; A second substrate is bonded to the side of the first substrate to which the mixture has been applied, wherein the mixture may optionally be applied to the second substrate; and The mixture is cured while being heated as needed. A method for bonding substrates, including [the specified element].

18. The method according to claim 17, wherein the first substrate and the second substrate are independently selected from metals selected from the group consisting of steel, stainless steel, carbon steel, iron, copper, aluminum, zinc, and alloys thereof; carbon fiber; glass fiber; glass; wood; plastic; and mixtures thereof.

19. The method according to claim 17, wherein the first substrate and the second substrate are independently selected from woven materials; nonwoven materials; and mixtures thereof.

20. An article comprising a cured product of the composition according to any one of claims 1 to 16.

21. Use of the composition according to any one of claims 1 to 16 in the assembly of ships, aircraft, automobiles, motorcycles or bicycles, or in construction.

Images