Moisture-resistant two-component adhesive composition

Abstract

The two-part adhesive composition comprises the reaction product of a polyol component comprising a hydrophobic polyol and a phosphoric acid functional adhesion promoter, and an isocyanate component comprising the reaction product of an isocyanate monomer and a dimer acid polyester polyol.

Description

[Technical Field]

[0001] The present disclosure relates to adhesive compositions, and more particularly to moisture-resistant two-part adhesive compositions. [Background technology]

[0002] Introduction In recent years, the adoption of electric vehicles (EVs) has been gaining momentum worldwide. A typical design for EV battery packs requires polyurethane (PU) adhesives to bond the battery cells and cooling plates. Adhesion strength can be measured by the shear strength of lap joints or the tensile strength of butt joints. Examples of bonding interfaces include aluminum alloys, PET films, and polycarbonates, with the most promising bonding interface being between aluminum alloys.

[0003] Additionally, the applied PU adhesive must be able to withstand moisture absorption, otherwise skinning can build up in the adhesive machine or bubbles can form after the PU adhesive is mixed and applied to the substrate. Both skinning and bubbles reduce line efficiency and lead to poor quality, making them unacceptable in production.

[0004] To provide moisture resistance, PU adhesives (especially two-component adhesives) are usually formulated with hydrophobic compounds such as castor oil or OH-terminated polybutadiene. These solutions are characterized by very weak adhesion at the Al-Al interface. For EV applications, the general requirements for moisture resistance and adhesive strength are summarized as a tack-free time of part B (isocyanate part) of more than 15 hours at 23°C / 45% humidity, an average lap joint adhesive shear strength of more than 7 MPa at the 3σ level, and an average butt joint adhesive tensile strength of more than 6.5 MPa at the 3σ level.

[0005] It is difficult for current two-component PU adhesives to simultaneously meet these requirements.

[0006] Therefore, there is a need for a PU adhesive that has high adhesive strength at the substrate, especially at the Al alloy-Al alloy interface, is inert to moisture absorption during adhesive application, and ensures that the average adhesive strength falls within the 3σ level range. Summary of the Invention

[0007] In a first aspect of the present disclosure, the present disclosure provides a method for producing a cellular membrane comprising: A) a polyol component comprising a hydrophobic polyol and a phosphate-functional adhesion promoter; B) a two-part adhesive composition comprising the reaction product of (I) an isocyanate monomer and (II) an isocyanate component comprising the reaction product of a dimer acid polyester polyol.

[0008] In a second aspect of the present disclosure, the present disclosure provides a method for producing a pharmaceutical composition comprising: a first substrate; a second substrate; a first substrate and a second substrate, and an adhesive layer formed from the two-part adhesive composition described herein.

[0009] In a third aspect of the disclosure, the disclosure provides a method of forming a two-part adhesive composition, the method comprising: (A) providing a polyol component A) comprising a hydrophobic polyol and a phosphate-functional adhesion promoter; (B) providing an isocyanate component B) comprising the reaction product of (I) an isocyanate monomer and (II) a dimer acid polyester polyol; and (C) reacting the isocyanate component B) with the polyol component A) to form the two-part adhesive composition described herein.

[0010] In a fourth aspect of the present disclosure, the present disclosure provides a use of a two-part adhesive composition in a battery pack.

[0011] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. DETAILED DESCRIPTION OF THE INVENTION

[0012] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Additionally, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

[0013] definition Numerical ranges disclosed herein include all values ​​between and including the lower and upper limits. Ranges that include explicit values ​​(e.g., a range of 1 or 2 or 3 to 5 or 6 or 7) also include any subranges between any two explicit values ​​(e.g., the range 1 to 7 above includes the subranges 1 to 2, 2 to 6, 5 to 7, 3 to 7, 5 to 6, etc.).

[0014] Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percentages are by weight and all test methods are current as of the filing date of this disclosure.

[0015] The term "composition" refers to a mixture of materials that comprise the composition, as well as reaction products and decomposition products formed from the materials of the composition.

[0016] The terms "comprising," "including," "having," and their derivatives are not intended to exclude the presence of any additional components, steps, or procedures, whether or not they are specifically disclosed herein. For the avoidance of doubt, all compositions claimed through the use of the term "comprising" may include any additional additives, adjuvants, or compounds, whether polymeric or not, unless specifically stated to the contrary. In contrast, the term "consisting essentially of" excludes from the scope of any subsequent description any other component, step, or procedure, except those that are not essential to operability. The term "consisting of" excludes any component, step, or procedure not expressly delineated or listed. The term "or" refers to the listed members individually and in any combination, unless otherwise stated. The use of the singular includes the use of the plural, and vice versa.

[0017] A "dicarboxylic acid" is a compound containing two carboxyl (-COOH) groups.

[0018] An "isocyanate" is a chemical substance containing at least one isocyanate group in its structure. An isocyanate group is represented by the formula: -N=C=O. An isocyanate containing more than one or at least two isocyanate groups is a "polyisocyanate." An isocyanate with two isocyanate groups is a diisocyanate, an isocyanate with three isocyanate groups is a triisocyanate, and so on. Isocyanates can be aromatic or aliphatic.

[0019] A "polyol" is an organic compound containing multiple hydroxyl (-OH) groups. In other words, a polyol contains at least two hydroxyl groups. Non-limiting examples of suitable polyols include diols (containing two hydroxyl groups), triols (containing three hydroxyl groups), and multi-hydroxyl-containing polyols.

[0020] A "polyether" is a compound containing two or more ether linkages in the same linear chain of atoms.

[0021] A "polyester" is a compound containing two or more ester bonds in the same linear chain of atoms.

[0022] A "polyester polyol" is a compound that is both a polyester and a polyol.

[0023] A "polymer" is a polymeric compound prepared by polymerizing monomers of the same or different types. Thus, the generic term "polymer" encompasses the term "homopolymer" (used to refer to a polymer prepared from only one type of monomer, with the understanding that trace amounts of impurities may be incorporated into the polymer structure), and the term "interpolymer" (used interchangeably with the term "copolymer") includes bipolymers (used to refer to a polymer prepared from two different monomers), terpolymers (used to refer to a polymer prepared from three different monomers), and polymers prepared from four or more different monomers. Trace amounts of impurities, such as catalyst residues, may be incorporated into and / or within the polymer. It also encompasses copolymers of all forms, e.g., random, block, etc. While polymers are often referred to as "made from" one or more specific monomers, "based on" a particular monomer or monomer type, or "containing" a particular monomer content, it should be noted that in this context, the term "monomer" is understood to refer to the polymerized remains of a particular monomer, not the unpolymerized species. Generally, polymers herein are based on "units" that are the polymerized form of the corresponding monomers.

[0024] A. Polyol component The two-part adhesive composition comprises the reaction product of A) a polyol component and B) an isocyanate component. Polyol component A) comprises a hydrophobic polyol and a phosphoric acid-functional adhesion promoter. Polyol component A) may optionally comprise an OH prepolymer and / or a polyether polyol.

[0025] Hydrophobic Polyol Hydrophobic polyol refers to a hydrophobic polyol having at least two hydroxyl groups.

[0026] In one embodiment, the hydrophobic polyol is castor oil or a derivative thereof.

[0027] Polyol component A contains 20 to 60 wt %, preferably 25 to 50 wt %, more preferably 28 to 45 wt %, and even more preferably 30 to 40 wt % of a hydrophobic polyol, preferably castor oil, based on the total weight of polyol component A.

[0028] Phosphate-functional adhesion promoter The phosphate-functional adhesion promoter is preferably a phosphate-modified polyol, more preferably a phosphate ester polyol. Phosphate ester polyols can be prepared from trifunctional propylene glycol, polyphosphoric acid, and polyisocyanate. Examples of commercially available trifunctional propylene glycols suitable for use in accordance with the present disclosure include products sold under the trade names VORANOL™ CP-450, VORANOL™ CP-260, VORANOL™ CP-755, and VORANOL™ CP-1055, each available from The Dow Chemical Company. In some embodiments, the phosphate ester polyol has a phosphate content of less than 4 weight percent based on the weight of the phosphate ester polyol, or a phosphate content of 0 to 3 weight percent based on the weight of the phosphate ester polyol, or a phosphate content of 1.5 to 2.5 weight percent based on the weight of the phosphate ester polyol. In some embodiments, the phosphate ester polyol has a viscosity of less than 40,000 cps at 25° C., or less than 30,000 cps at 25° C., as measured by the method of ASTM D2196. In some embodiments, the phosphate ester polyol has a hydroxyl equivalent weight of less than 330 g / mol. In some embodiments, the phosphate ester polyol has from 0 to 100 weight percent, based on the weight of the phosphate ester polyol, of a trifunctional polyether polyol having an equivalent weight of less than 2,000 g / mol.

[0029] Polyol component A) comprises 0.1 to 20 wt. %, preferably 0.2 to 15 wt. %, more preferably 0.5 to 12 wt. %, even more preferably 1 to 10 wt. %, more preferably 2 to 8 wt. % of a phosphate-functional adhesion promoter, preferably a phosphate ester polyol, based on the total weight of polyol component A.

[0030] OH prepolymer Polyol component A) may optionally further comprise an OH prepolymer, which is the reaction product of a reaction mixture comprising (i) an isocyanate monomer, (ii) a polyol, and (iii) castor oil.

[0031] An "isocyanate monomer" is a molecule containing at least two isocyanate groups. The isocyanate monomer can be chemically bonded to a polyol to form a prepolymer. Non-limiting examples of suitable isocyanate monomers include aromatic isocyanates, aliphatic isocyanates, carbodiimide-modified isocyanate monomers, and combinations thereof.

[0032] The "aromatic isocyanate monomer" is an isocyanate monomer containing one or more aromatic rings. Non-limiting examples of suitable aromatic isocyanate monomers include isomers of methylene diphenyl dipolyisocyanate (MDI), such as 4,4-MDI, 2,4-MDI, and 2,2'-MDI; modified MDI, such as carbodiimide-modified MDI or allophanate-modified MDI; isomers of toluene-dipolyisocyanate (TDI), such as 2,4-TDI and 2,6-TDI; isomers of naphthalene-dipolyisocyanate (NDI), such as 1,5-NDI; and combinations thereof.

[0033] An "aliphatic isocyanate monomer" is an isocyanate monomer in which the isocyanate moiety (-NCO) is not directly attached to an aromatic ring. Non-limiting examples of suitable aliphatic isocyanate monomers include isomers of hexamethylene dipolyisocyanate (HDI), isophorone dipolyisocyanate (IPDI), isomers of xylene dipolyisocyanate (XDI), methylene biscyclohexyl isocyanate (hydrogenated MDI) (HMDI) and other cycloaliphatic isocyanates such as cyclohexane diisocyanate, and combinations thereof.

[0034] In one embodiment, the isocyanate monomer is selected from a monoisocyanate monomer, a diisocyanate monomer, a triisocyanate monomer, and combinations thereof. In a further embodiment, the isocyanate monomer is a diisocyanate monomer.

[0035] In one embodiment, the isocyanate monomer is a multifunctional isocyanate monomer having at least two isocyanate groups, or at least three isocyanate groups.

[0036] In one embodiment, the isocyanate monomer is selected from MDI, TDI, HDI, and combinations thereof. In a further embodiment, the isocyanate monomer is MDI.

[0037] In one embodiment, the isocyanate monomer is selected from carbodiimide-modified MDI, carbodiimide-modified TDI, carbodiimide-modified HDI, and combinations thereof. In a further embodiment, the isocyanate monomer is a carbodiimide-modified MDI, such as ISONATE 143L from The Dow Chemical Company.

[0038] The polyol for preparing the OH prepolymer may be a polyester polyol, a polyether polyol, or a combination thereof, and is preferably a polyether polyol. "Polyether polyol" is a compound that is both a polyether and a polyol. Non-limiting examples of suitable polyether polyols include polyaddition products of ethylene oxide, propylene oxide, tetrahydrofuran, butylene oxide, and their co-addition products and graft products, polyether polyols obtained by condensation of polyhydric alcohols, or mixtures thereof, and combinations thereof.

[0039] Non-limiting examples of suitable polyether polyols include polypropylene glycol (PPG), polyethylene glycol (PEG), polybutylene glycol, polytetramethylene ether glycol (PTMEG), and combinations thereof. In one embodiment, the polyether polyol is polypropylene glycol (PPG).

[0040] Non-limiting examples of suitable polyether polyols include VORANOL™ 1010 L (PPG) and VORANOL™ CP450 (glycerin propoxylated polyether triol), each available from The Dow Chemical Company.

[0041] In one embodiment, the polyether polyol has a Mw of 50 g / mol or 100 g / mol or 400 g / mol or 450 g / mol to 1,000 g / mol or 1,500 g / mol or 2,000 g / mol or 4,000 g / mol or 5,000 g / mol.

[0042] In one embodiment, the polyether polyol has a hydroxyl number of 30 mg KOH / g or 50 mg KOH / g or 75 mg KOH / g or 100 mg KOH / g to 115 mg KOH / g or 125 mg KOH / g or 150 mg KOH / g or 200 mg KOH / g or 300 mg KOH / g or 350 mg KOH / g or 400 mg KOH / g or 450 mg KOH / g or 500 mg KOH / g.

[0043] In one embodiment, the polyether polyol has one or both of the following characteristics: (i) a Mw of 50 g / mol to 5,000 g / mol, or 100 g / mol to 2,000 g / mol, or 400 g / mol to 1,500 g / mol, or 400 g / mol to 1,000 g / mol, and / or (ii) a hydroxyl number of 30 mg KOH / g to 500 mg KOH / g, or 100 mg KOH / g to 400 mg KOH / g, or 100 mg KOH / g to 150 mg KOH / g, or 350 mg KOH / g to 400 mg KOH / g.

[0044] Polyol component A) comprises 0 to 30 wt. %, preferably 2 to 28 wt. %, more preferably 4 to 25 wt. %, even more preferably 6 to 20 wt. %, or 8 to 18 wt. %, or 10 to 15 wt. % of OH prepolymer, based on the total weight of polyol component A).

[0045] Polyether polyol The polyol component A) may further comprise a polyether polyol. A "polyether polyol" is a compound that is both a polyether and a polyol. Non-limiting examples of suitable polyether polyols include polyaddition products of ethylene oxide, propylene oxide, tetrahydrofuran, butylene oxide, and their coaddition and graft products, polyether polyols obtained by condensation of polyhydric alcohols, or mixtures thereof, and combinations thereof.

[0046] Non-limiting examples of suitable polyether polyols include polypropylene glycol (PPG), polyethylene glycol (PEG), polybutylene glycol, polytetramethylene ether glycol (PTMEG), and combinations thereof. In one embodiment, the polyether polyol is polypropylene glycol (PPG).

[0047] Non-limiting examples of suitable polyether polyols include VORANOL™ 1010 L (PPG) and VORANOL™ CP450 (glycerin propoxylated polyether triol), each available from The Dow Chemical Company.

[0048] In one embodiment, the polyether polyol has a Mw of 50 g / mol or 100 g / mol or 400 g / mol or 450 g / mol to 1,000 g / mol or 1,500 g / mol or 2,000 g / mol or 4,000 g / mol or 5,000 g / mol.

[0049] In one embodiment, the polyether polyol has a hydroxyl number of 30 mg KOH / g or 50 mg KOH / g or 75 mg KOH / g or 100 mg KOH / g to 115 mg KOH / g or 125 mg KOH / g or 150 mg KOH / g or 200 mg KOH / g or 300 mg KOH / g or 350 mg KOH / g or 400 mg KOH / g or 450 mg KOH / g or 500 mg KOH / g.

[0050] In one embodiment, the polyether polyol has one or both of the following characteristics: (i) a Mw of 50 g / mol to 5,000 g / mol, or 100 g / mol to 2,000 g / mol, or 400 g / mol to 1,500 g / mol, or 400 g / mol to 1,000 g / mol, and / or (ii) a hydroxyl number of 30 mg KOH / g to 500 mg KOH / g, or 100 mg KOH / g to 400 mg KOH / g, or 100 mg KOH / g to 150 mg KOH / g, or 350 mg KOH / g to 400 mg KOH / g.

[0051] Polyol component A) comprises 1 to 20 wt. %, preferably 2 to 15 wt. %, more preferably 4 to 12 wt. %, and even more preferably 6 to 10 wt. % of a polyether polyol, preferably a glycerin propoxylated polyether triol, based on the total weight of polyol component A.

[0052] Chain extender The polyol component A) may optionally include a chain extender. Non-limiting examples of suitable chain extenders include glycerin, trimethylolpropane, diethylene glycol, propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol (BDO), and combinations thereof, preferably 1,4-butanediol (BDO).

[0053] Polyol component A) comprises 1 to 20 wt. %, preferably 2 to 15 wt. %, more preferably 4 to 10 wt. %, and even more preferably 2 to 6 wt. % of a chain extender, preferably 1,4-butanediol (BDO), based on the total weight of polyol component A.

[0054] Polyol component A) may optionally contain moisture scavengers, catalysts, flame retardants, rheology modifiers, fillers, and the like.

[0055] Moisture scavengers absorb moisture from the environment before it can react with NCO-containing groups in the adhesive and cause bubble formation problems. An example of a moisture scavenger often used in polyurethane adhesives is molecular sieves.

[0056] The catalyst adjusts the reaction rate to meet process requirements. Higher catalyst loadings help increase initial bond strength but shorten pot life. A balanced catalyst package is organometallic with Zn, Bi, and Sn-containing catalysts.

[0057] Flame retardants such as isopropylated phenol phosphate improve the fire resistance of the battery cells when they are exposed to an electrical short circuit.

[0058] Rheology modifiers are often included in either the polyol component A) or the isocyanate component B), or both, of the adhesive composition to provide thixotropic properties to suit various application needs.

[0059] Fillers can be added to either the polyol component A) or the isocyanate component B) of the adhesive composition, or both, to improve mechanical strength and reduce costs. Fillers can be selected from silica, CaCO3, kaolin, talc, ATH, etc.

[0060] B. Isocyanate component The two-part adhesive composition comprises the reaction product of A) a polyol component and B) an isocyanate component. The isocyanate component B) comprises the reaction product of (I) an isocyanate monomer and (II) a dimer acid polyester polyol that is an NCO-terminated prepolymer.

[0061] An "NCO-terminated prepolymer" is the reaction product of an isocyanate monomer and at least one polyol, where the at least one polyol comprises a dimer acid polyester polyol. The isocyanate prepolymer is an intermediate between the monomer and the final polymer.

[0062] Isocyanate Monomer The isocyanate component comprises the reaction product of (i) an isocyanate monomer and (ii) a dimer acid polyester polyol.

[0063] An "isocyanate monomer" is a molecule containing at least two isocyanate groups. The isocyanate monomer can be chemically bonded to a polyol to form a prepolymer. Non-limiting examples of suitable isocyanate monomers include aromatic isocyanates, aliphatic isocyanates, carbodiimide-modified isocyanate monomers, and combinations thereof.

[0064] The "aromatic isocyanate monomer" is an isocyanate monomer containing one or more aromatic rings. Non-limiting examples of suitable aromatic isocyanate monomers include isomers of methylene diphenyl dipolyisocyanate (MDI), such as 4,4-MDI, 2,4-MDI, and 2,2'-MDI; modified MDI, such as carbodiimide-modified MDI or allophanate-modified MDI; isomers of toluene-dipolyisocyanate (TDI), such as 2,4-TDI and 2,6-TDI; isomers of naphthalene-dipolyisocyanate (NDI), such as 1,5-NDI; and combinations thereof.

[0065] An "aliphatic isocyanate monomer" is an isocyanate monomer in which the isocyanate moiety (-NCO) is not directly attached to an aromatic ring. Non-limiting examples of suitable aliphatic isocyanate monomers include isomers of hexamethylene dipolyisocyanate (HDI), isophorone dipolyisocyanate (IPDI), isomers of xylene dipolyisocyanate (XDI), methylene biscyclohexyl isocyanate (hydrogenated MDI or HMDI) and other cycloaliphatic isocyanates such as cyclohexane diisocyanate, and combinations thereof.

[0066] In one embodiment, the isocyanate monomer is selected from a monoisocyanate monomer, a diisocyanate monomer, a triisocyanate monomer, and combinations thereof. In a further embodiment, the isocyanate monomer is a diisocyanate monomer.

[0067] In one embodiment, the isocyanate monomer is a multifunctional isocyanate monomer having at least two isocyanate groups, or at least three isocyanate groups.

[0068] In one embodiment, the isocyanate monomer is selected from MDI, TDI, HDI, and combinations thereof. In a further embodiment, the isocyanate monomer is MDI.

[0069] In one embodiment, the isocyanate monomer is selected from carbodiimide-modified MDI, carbodiimide-modified TDI, carbodiimide-modified HDI, and combinations thereof. In a further embodiment, the isocyanate monomer is carbodiimide-modified MDI.

[0070] In one embodiment, the isocyanate monomer has an NCO content of 20% or greater, preferably 25% or greater, preferably 28% or greater.

[0071] Dimer acid polyester polyol Isocyanate component B) comprises the reaction product of (i) an isocyanate monomer and (ii) a dimer acid polyester polyol. "Dimer acid polyester polyol" (or "DAPP" or dimer acid-based polyester polyol) is a polyester polyol comprising units derived from dimer acid. In one embodiment, DAPP is the reaction product of (i) a dimer acid, (ii) a polyol, and (iii) optionally a dicarboxylic acid.

[0072] i. Dimer acid In one embodiment, DAPP is the reaction product of a reaction mixture comprising (i) a dimer acid, (ii) a polyol, and (iii) optionally a dicarboxylic acid.

[0073] A "dimer acid" is a dicarboxylic acid compound obtained by reacting a fatty acid having 2 to 4 ethylenic double bonds and 14 to 22 carbon atoms (hereinafter referred to as "unsaturated fatty acid A") with a fatty acid having 1 to 4 ethylenic double bonds and 14 to 22 carbon atoms (hereinafter referred to as "unsaturated fatty acid B") at the double bond in a dimerization reaction. In one embodiment, unsaturated fatty acid A has two ethylenic double bonds and 14 to 22 carbon atoms, and unsaturated fatty acid B has one or two ethylenic double bonds and 14 to 22 carbon atoms. Non-limiting examples of suitable unsaturated fatty acids A include tetradecadienoic acid, hexadecadienoic acid, octadecadienoic acid (e.g., linoleic acid), eicosadienoic acid, docosadienoic acid, octadecatrienoic acid (e.g., linolenic acid), eicosatetraenoic acid (e.g., arachidonic acid), and combinations thereof. Non-limiting examples of suitable unsaturated fatty acids B include, in addition to the examples above, tetradecenoic acids (such as tsuzuic acid, physeteric acid, myristoleic acid), hexadecenoic acids (such as palmitoleic acid), octadecenoic acids (such as oleic acid, elaidic acid, vaccenic acid), eicosenoic acids (such as gadoleic acid), and docosenoic acids (such as erucic acid, cetoleic acid, and brassidic acid), and combinations thereof.

[0074] The resulting dimer acid is a mixture of dimer acids whose structures vary depending on the attachment site or isomerization of the double bond. Non-limiting examples of suitable dimer acid structures are the following structures (A), (B), (C), (D), or (E):

[0075] [ka]

[0076] [ka]

[0077] In one embodiment, the dimer acid is a C36 dimer acid. In a further embodiment, the C36 dimer acid has the structure (A):

[0078] In one embodiment, the resulting dimer acid contains 0% to 2%, or 4%, or 6% by weight of monomer acid and / or 0% to 2%, or 4%, or 6% by weight of polymer acid and has a degree of polymerization equal to or greater than that of the trimer acid.

[0079] In one embodiment, the dimer acid is unsaturated. An "unsaturated dimer acid" contains at least one carbon-carbon double bond. Structure (A) is an unsaturated dimer acid. A non-limiting example of a suitable dimer acid is ATUREX™ 1001 (CAS 61788-89-4), available from the Aturex Group.

[0080] In one embodiment, the dimer acid has an acid number of 150 mg KOH / g, or 160 mg KOH / g, or 170 mg KOH / g, or 180 mg KOH / g, or 190 mg KOH / g, or 194 mg KOH / g to 200 mg KOH / g, or 210 mg KOH / g, or 220 mg KOH / g, or 230 mg KOH / g, or 240 mg KOH / g, or 250 mg KOH / g. In another embodiment, the dimer acid has an acid number of 150 mg KOH / g to 250 mg KOH / g, or 180 mg KOH / g to 220 mg KOH / g, or 190 mg KOH / g to 200 mg KOH / g.

[0081] In one embodiment, the dimer acid has structure (A) and has an acid number of from 150 mg KOH / g to 250 mg KOH / g, or from 180 mg KOH / g to 220 mg KOH / g, or from 190 mg KOH / g to 200 mg KOH / g. In a further embodiment, the dimer acid is ATUREX™ 1001 (CAS 61788-89-4), available from the Aturex Group.

[0082] The dimer acid may comprise two or more embodiments disclosed herein.

[0083] ii. Polyol In one embodiment, DAPP is the reaction product of a reaction mixture comprising (i) a dimer acid, (ii) a polyol, and (iii) optionally a dicarboxylic acid.

[0084] Non-limiting examples of suitable polyols include diols (containing two hydroxyl groups), triols (containing three hydroxyl groups), and combinations thereof. In one embodiment, the polyol comprises a diol and a triol.

[0085] Non-limiting examples of suitable diols include 3-methyl-1,5-pentanediol (MPD), 2-methyl-1,3-propanediol (MPG), ethylene glycol, butylene glycol, diethylene glycol (DEG), triethylene glycol, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol (NPG).

[0086] A non-limiting example of a suitable triol is trimethylolpropane (TMP).

[0087] In one embodiment, the polyol is a diol. In a further embodiment, the diol is MPD.

[0088] The polyol may comprise two or more embodiments disclosed herein.

[0089] iii. Any dicarboxylic acid In one embodiment, DAPP is the reaction product of a reaction mixture comprising (i) a dimer acid, (ii) a polyol, and (iii) optionally a dicarboxylic acid.

[0090] The (iii) dicarboxylic acid is not a dimer acid. In other words, the (iii) dicarboxylic acid is structurally and / or compositionally different from the (i) dimer acid in the reaction mixture.

[0091] Non-limiting examples of suitable dicarboxylic acids include fatty acids, aromatic acids, and combinations thereof. Non-limiting examples of suitable aromatic dicarboxylic acids include phthalic acid, isophthalic acid, and terephthalic acid. Non-limiting examples of suitable aliphatic dicarboxylic acids include cyclohexanedicarboxylic acid, adipic acid, azelaic acid, sebacic acid, glutaric acid, maleic acid, fumaric acid, itaconic acid, malonic acid, suberic acid, 2-methylsuccinic acid, 3,3-diethylglutaric acid, 2,2-dimethylsuccinic acid, and trimellitic acid. As used herein, the term "acid" also includes any anhydride of the acid. Saturated aliphatic and / or aromatic acids, such as adipic acid or isophthalic acid, are also suitable.

[0092] In one embodiment, the dicarboxylic acid has 4, or 5, or 6-7, or 8, or 9, or 10 carbon atoms. In another embodiment, the dicarboxylic acid has 4-10 carbon atoms, or 6-8 carbon atoms. In a further embodiment, the dicarboxylic acid has 8 carbon atoms.

[0093] In one embodiment, the dicarboxylic acid is selected from phthalic acid, isophthalic acid, terephthalic acid, and combinations thereof.

[0094] The dicarboxylic acid may comprise two or more embodiments disclosed herein.

[0095] iv. Optional Additives In one embodiment, DAPP is the reaction product of a reaction mixture comprising (i) a dimer acid, (ii) a polyol, (iii) optionally a dicarboxylic acid, and (iv) optionally an additive.

[0096] Non-limiting examples of suitable optional additives include adhesion promoters, chain extenders, catalysts, and combinations thereof.

[0097] A non-limiting example of a suitable adhesion promoter is an aminosilane.

[0098] Non-limiting examples of suitable chain extenders include glycerin, trimethylolpropane, diethylene glycol, propanediol, 2-methyl-1,3-propanediol, and combinations thereof.

[0099] Non-limiting examples of suitable catalysts include tetra-n-butyl titanate, zinc sulfate, organotin catalysts, and combinations thereof.

[0100] In one embodiment, the reaction mixture excludes a chain extender.

[0101] Any additive may comprise more than one embodiment disclosed herein.

[0102] Isocyanate component B) may optionally contain plasticizers, flame retardants, adhesion promoters, rheology modifiers, fillers, and the like.

[0103] Plasticizers such as diisononyl phthalate help reduce the skinning that builds up during application of the isocyanate component B).

[0104] Flame retardants such as isopropylated phenol phosphate improve the fire resistance of the battery cells when they are exposed to an electrical short circuit.

[0105] Conventional adhesion promoters such as epoxy silanes may also be used.

[0106] Rheology modifiers such as fumed silica are often included in adhesive compositions to provide thixotropic properties to suit various application needs. In the isocyanate component B), fumed silica with a hydrophobic surface treatment is often used as a rheology modifier.

[0107] Fillers are added to the adhesive composition to improve mechanical strength and reduce costs, and the fillers can be selected from silica, CaCO3, kaolin, talc, etc.

[0108] The mixture for preparing the reaction product of (i) an isocyanate monomer and (ii) a dimer acid polyester polyol (also called an NCO-terminated prepolymer) typically contains 60 to 95 wt %, preferably 65 to 85 wt %, and more preferably 70 to 80 wt % of an aromatic isocyanate and 5 to 40 wt %, preferably 15 to 35 wt %, and more preferably 20 to 30 wt % of a dimer acid polyester polyol, based on the total weight of the mixture for preparing the reaction product of (i) an isocyanate monomer and (ii) a dimer acid polyester polyol.

[0109] Isocyanate component B) typically comprises, based on the total weight of isocyanate component B), 30 to 100 wt%, preferably 35 to 95 wt%, more preferably 40 to 90 wt%, even more preferably 40 to 80 wt%, or 50 to 75 wt%, or 60 to 75 wt%, of a reaction product of (i) an isocyanate monomer and (ii) a dimer acid polyester polyol, optionally 0 to 20 wt%, preferably 1 to 10 wt%, more preferably 0.5 to 8 wt%, even more preferably 1 to 5 wt%, or 2 to 4 wt%, of a plasticizer, and 0 to 20 wt%, preferably 0.1 to 10 wt%, based on the total weight of isocyanate component B). , more preferably 0.5 to 8 wt%, even more preferably 0.8 to 5 wt% or 1 to 3 wt% of a flame retardant, 0 to 10 wt%, preferably 1 to 8 wt%, more preferably 0.5 to 6 wt%, even more preferably 0.8 to 5 wt% or 1 to 4 wt% of an adhesion promoter, 0 to 10 wt%, preferably 0.5 to 8 wt%, even more preferably 1 to 5 wt% or 2 to 4 wt% of a rheology modifier, and 0 to 70 wt%, preferably 5 to 65 wt%, more preferably 10 to 50 wt%, even more preferably 18 to 45 wt%, or 20 to 40 wt%, or 20 to 30 wt% of a filler.

[0110] C. Two-component adhesive composition The two-part adhesive composition is free or substantially free of solvents.

[0111] In one embodiment, the two-part adhesive composition includes any conventional additive, which may be any additive disclosed herein, such as a plasticizer, a chain extender, a flame retardant, an adhesion promoter, a rheology modifier, a filler, a moisture scavenger, a catalyst, or the like.

[0112] The two-part adhesive composition is formed by mixing polyol component A) and isocyanate component B) under conditions suitable for reacting the -NCO groups of the isocyanate component with the hydroxyl groups of the polyol component. In one embodiment, polyol component A) and isocyanate component B) are mixed via static or dynamic mixing equipment (such as a meter mix dispenser) at a temperature of 15°C, 20°C, 25°C, 30°C, 35°C, 40°C to 45°C, 50°C, or 55°C.

[0113] Isocyanate Index or ("NCO Index") is the molar ratio of isocyanate groups in the isocyanate component to the amount of hydroxyl groups in the polyol component. NCO Index is calculated according to the following equation (2):

[0114]

number

[0115] In one embodiment, the two-part adhesive composition has an NCO index of 1.00 or 1.05 or 1.10 or 1.15 to 1.50 or 1.40 or 1.30 or 1.25. In another embodiment, the two-part adhesive composition has an NCO index of 1.00 to 1.50, or 1.05 to 1.40, or 1.10 to 1.30, or 1.15 to 1.25.

[0116] In one embodiment, the two-part adhesive composition comprises polyol component A) and isocyanate component B) in a volume ratio of isocyanate component B):polyol component A) of 120:100 to 80:100, or 115:100 to 90:100, or 110:100 to 95:100, or 105:100 to 98:100.

[0117] The two-part adhesive composition may comprise two or more embodiments disclosed herein.

[0118] D.Multilayer structure The present disclosure provides a multilayer structure comprising a first substrate, a second substrate, and an adhesive layer between the first substrate and the second substrate, the adhesive layer being formed from a two-component adhesive composition.

[0119] The two-part adhesive composition can be any two-part adhesive composition disclosed herein.

[0120] First substrate and second substrate The multi-layer structure includes a first substrate and a second substrate.

[0121] The first substrate and the second substrate can be the same or different, hi one embodiment, the first substrate and the second substrate are the same, and therefore, they have the same composition and the same structure.

[0122] In one embodiment, the first substrate and the second substrate are compositionally and / or structurally different from one another.

[0123] Any description below that refers to a "substrate" will be understood to refer to a first substrate and a second substrate individually and / or collectively.

[0124] A non-limiting example of a suitable substrate is a film. The film may be a single-layer film or a multilayer film. A multilayer film includes two layers or three or more layers. For example, a multilayer film may have 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or more layers. In one embodiment, the multilayer film includes only two layers or only three layers.

[0125] In one embodiment, the film is a monolayer film having only one layer.

[0126] In one embodiment, the film includes a layer containing a component selected from ethylene-based polymers (PE), propylene-based polymers (PP), polyamides (such as nylon), polyesters, ethylene-vinyl alcohol (EVOH) copolymers, polyethylene terephthalate (PET), ethylene-vinyl acrylate (EVA) copolymers, ethylene-methyl acrylate copolymers, ethylene-ethyl acrylate copolymers, ethylene-butyl acrylate copolymers, ethylene-acrylic acid copolymers, ethylene-methacrylic acid copolymers, ionomers of ethylene-acrylic acid, ionomers of methacrylic acid, maleic anhydride-grafted ethylene-based polymers, polylactic acid (PLA), polystyrene, metal foils, cellulose, cellophane, nonwoven fabrics, and combinations thereof. A non-limiting example of a suitable metal foil is aluminum foil. Each layer of the multilayer film may be formed from the same or different components.

[0127] In one embodiment, the film includes a layer containing a metal foil.

[0128] In one embodiment, the film is a monolayer film having a single layer that is an ethylene-based polymer layer. In a further embodiment, the film is a monolayer film having a single layer that is a polyethylene layer.

[0129] Substrates, and also films, are continuous structures having two opposing surfaces.

[0130] In one embodiment, the substrate has a thickness of 5 μm or 10 μm or 12 μm or 15 μm or 20 μm or 21 μm to 23 μm or 24 μm or 25 μm or 30 μm or 35 μm or 40 μm or 45 μm or 50 μm or 100 μm or 150 μm or 200 μm or 250 μm or 300 μm or 350 μm or 400 μm or 450 μm or 500 μm.

[0131] In one embodiment, the substrate excludes cellulosic substrates such as paper and wood.

[0132] In one embodiment, the first substrate is a monolayer film having a single layer that is a PE layer, and the second substrate is a film having a layer that is a metal foil layer.

[0133] The film may comprise two or more embodiments disclosed herein.

[0134] The first substrate may include two or more embodiments disclosed herein.

[0135] The second substrate may comprise two or more embodiments disclosed herein.

[0136] The two-part adhesive composition is applied between the first and second substrates using, for example, a Nordmeccanica Labo Combi 400 laminator. In one embodiment, the two-part adhesive composition is applied between the first and second substrates at a temperature of 20°C, 30°C, or 40°C to 50°C, 60°C, 70°C, 80°C, or 90°C.

[0137] Non-limiting examples of suitable application methods include brushing, pouring, spraying, coating, rolling, sprinkling, and injecting.

[0138] In one embodiment, the two-part adhesive composition is applied between a first substrate and a second substrate by conventional coating methods.

[0139] In one embodiment, the two-component adhesive composition is applied uniformly between a first substrate and a second substrate. A "uniform application" is a layer of composition that is continuous (not intermittent) across the surface of the substrate and that is the same or substantially the same thickness across the surface of the substrate. In other words, a composition that is applied uniformly to a substrate is in direct contact with the substrate surface and is coextensive with the substrate surface.

[0140] The two-component adhesive composition and the first substrate are in direct contact with each other. As used herein, the term "direct contact" refers to a layer configuration in which the substrate is placed directly adjacent to the two-component adhesive composition or adhesive layer, with no intervening layer or structure between the substrate and the two-component adhesive composition or adhesive layer. The two-component adhesive composition is in direct contact with the surface of the first substrate.

[0141] The two-part adhesive composition and the second substrate are in direct contact with each other. The two-part adhesive composition directly contacts the surface of the second substrate.

[0142] The structure comprising a first substrate, a second substrate, and a two-part adhesive composition has the following structure (P):

[0143]

number

[0144] The adhesive layer of structure (P) is formed by curing a two-component adhesive composition. The two-component adhesive composition is formed by mixing and reacting a polyol component (A) and an isocyanate component (B).

[0145] In one embodiment, the two-part adhesive composition is cured in an oven at a temperature of 10°C, 20°C, or 35°C to 40°C, or 45°C, or 50°C.

[0146] In one embodiment, the two-part adhesive composition is cured at a temperature of 20° C. to 30° C., preferably 25° C., for 1 to 2 days, or 4 days, or 7 days, or 10 days.

[0147] In one embodiment, the two-part adhesive composition is cured in the absence, or substantially absence, of a photoinitiator.

[0148] In one embodiment, the two-part adhesive composition is cured in the absence or substantial absence of water.

[0149] In one embodiment, Structure (P) is cured to form an adhesive layer between the first substrate and the second substrate, thereby forming a multilayer structure. The multilayer structure has the following Structure (Q):

[0150]

number

[0151] The multi-layer structure includes a first substrate in direct contact with the adhesive layer and a second substrate in direct contact with the adhesive layer.

[0152] The multilayer structure includes alternating substrate and adhesive layers. The multilayer structure includes at least three layers in total, including substrate and adhesive layers. In one embodiment, the multilayer structure includes three to four layers in total, or five layers, or six layers, or seven layers, or eight layers, or nine layers, or ten layers.

[0153] In one embodiment, the first substrate is a monolayer film having a single layer that is a metal foil layer, the second substrate is a monolayer film having a single layer that is a metal foil layer, and the multilayer structure has a lap shear strength of 7 MPa or 7.5 MPa or 8 MPa to 15 MPa or 13 MPa or 12 MPa, and / or a cross tensile strength of 6.5 MPa or 7.0 MPa or 7.5 MPa to 15 MPa or 13 MPa or 12 MPa.

[0154] In one embodiment, the first substrate is a monolayer film having a single layer that is a metal foil layer, and the second substrate is a film having a layer that is a metal foil layer, and the multilayer structure has an average lap joint adhesive shear strength at the 3σ level of >7 MPa, or 7.5 MPa, or 8 MPa to 15 MPa, or 13 MPa or 12 MPa, and an average butt joint adhesive tensile strength at the 3σ level of 6.5 MPa, or 6.7 MPa, or 7.0 MPa, or 7.5 MPa to 15 MPa, or 13 MPa or 12 MPa.

[0155] E. Method for Forming a Two-Part Solventless Adhesive Composition The present disclosure also provides a method of forming a two-part adhesive composition, the method comprising: (A) providing a polyol component A) comprising a hydrophobic polyol and a phosphate-functional adhesion promoter; (B) providing an isocyanate component B) comprising the reaction product of (I) an isocyanate monomer and (II) a dimer acid polyester polyol; (C) reacting the isocyanate component B) with the polyol component A) to form a two-part adhesive composition.

[0156] The multi-layer structure may be in the form of a jelly roll or laminate, preferably within a battery package.

[0157] The present disclosure also provides articles comprising the multi-layer structure. Non-limiting examples of suitable articles include packages, such as battery packages.

[0158] By way of example, and not limitation, some embodiments of the present disclosure will now be described in detail in the following examples. [Example]

[0159] The materials used in the examples are shown in Table 1 below.

[0160] [Table 1]

[0161] Synthesis of dimer fatty acid polyester diol-A: 100g of neopentyl glycol, 99g of adipic acid, and 81.5g of ATUREX-1001 were added to a 500ml glass reactor and thoroughly mixed. The mixture was heated to 100°C. Agitation was initiated once the raw materials became liquid. The temperature was controlled appropriately and monitored throughout the process. If the maximum temperature of the glass condenser exceeded 103°C, the reactor was cooled as quickly as possible. The reaction temperature rose to 220°C. When the maximum temperature fell below 100°C, a vacuum was slowly applied over 30 minutes to 30mmHg. The acid value was checked every 30 minutes. A certain amount of catalyst, Tyzor TBT, was added until the acid value was below 10. After the catalyst was added, the reaction system was maintained at a vacuum of 30mmHg for at least 1 hour until the OH value of the reaction system reached the theoretical value. The mixture was cooled to 60-70°C, and the final product, dimer fatty acid-based polyester diol-A, was collected.

[0162] Synthesis of dimer fatty acid polyester diol-B: 100g of 1,6-hexanediol and 353g of ATUREX-1001 were added to a 500ml glass reactor and thoroughly mixed. The mixture was heated to 100°C. Agitation was initiated once the raw materials became liquid. The temperature was controlled appropriately and monitored throughout the process. If the maximum temperature of the glass condenser exceeded 103°C, the reactor was cooled as quickly as possible. The reaction temperature rose to 220°C. When the maximum temperature fell below 100°C, a vacuum was slowly applied over 30 minutes to 30mmHg. The acid value was checked every 30 minutes. A certain amount of catalyst, Tyzor TBT, was added until the acid value of the reaction system was below 10. After the catalyst was added, the reaction system was maintained at a vacuum of 30mmHg for at least 1 hour until the OH value of the reaction system reached the theoretical value. The mixture was cooled to 60-70°C, and the final product, dimer fatty acid-based polyester diol-B, was collected.

[0163] Synthesis of phosphoric acid-modified polyol The synthesis of phosphoric acid-modified polyol is described in Example 5 of WO 2015 / 168670 A1: A 1 L multi-neck round-bottom flask was dried in an oven and flushed with dry N for 30 minutes, then charged with VORANOL™ CP 450 polyether polyol (150 g) and placed under a 70 mL / min N sweep. A syringe was charged with 115% polyphosphoric acid (PPA) (4 g) from Aldrich Chemical Co. The PPA was added dropwise to the polyether polyol with vigorous stirring. Minimal temperature increase was observed. The reactor contents were heated to 100°C for 1 hour and then cooled to 45°C. ISONATE™ 125M polyisocyanate (50 g) was added. The exotherm of reaction caused the temperature to rise to approximately 95°C. There was also an increase in viscosity and the development of a yellow color. The reactor was then brought to 65°C and ethyl acetate (40 g) was added to reduce the viscosity and improve stirring. After 1 hour, the reactor was cooled and the contents were packaged (viscosity: 42,750 mPa.s).

[0164] Synthesis of OH-terminated prepolymer: An OH-terminated prepolymer was synthesized in a 1,000 ml glass reactor as a standard polyurethane prepolymer preparation process. 12 g of ISONATE OP 50 was added to the reactor and maintained at 60°C under nitrogen protection. 44 g of castor oil and 44 g of VORANOL P 400 were then added to the reactor and mixed with the ISONATE OP 50. The temperature was slowly raised to 80°C and maintained for 2 hours. Finally, the prepolymer was packed into a nitrogen-protected, tightly sealed container for further use.

[0165] Synthesis of NCO-terminated prepolymer 1: 75 g of ISONATE 143L was charged into a 1,000 ml glass reactor and maintained at 60 °C under nitrogen protection. 25 g of dimer fatty acid-based polyester diol A was then charged into the reactor and mixed with ISONATE 143L. The temperature was slowly raised to 80 °C and maintained for 2-3 hours until the NCO content reached the theoretical value. Finally, the prepolymer was charged into a well-sealed container under nitrogen protection for further application.

[0166] Synthesis of NCO-terminated prepolymer 2: 75 g of ISONATE 143L was charged into a 1,000 ml glass reactor and maintained at 60 °C under nitrogen protection. 25 g of dimer fatty acid-based polyester diol B was then added to the reactor and mixed with ISONATE 143L. The temperature was slowly raised to 80 °C and maintained for 2-3 hours until the NCO content reached the theoretical value. Finally, the prepolymer was charged into a well-sealed container under nitrogen protection for further application.

[0167] Synthesis of NCO-terminated prepolymer 3: 75 g of ISONATE 143L was charged into a 1,000 ml glass reactor and maintained at 60 °C under nitrogen protection. 25 g of castor oil was then added to the reactor and mixed with ISONATE 143L. The temperature was slowly raised to 80 °C and held for 2-3 hours until the NCO content reached the theoretical value. Finally, the prepolymer was charged into a well-sealed container under nitrogen protection for further application.

[0168] Synthesis of NCO-terminated prepolymer 4: 73 g of ISONATE 143L was charged into a 1,000 ml glass reactor and maintained at 60 °C under nitrogen protection. Then, 24 g of dimer fatty acid-based polyester diol A and 3 g of phosphoric acid-modified polyol were added to the reactor and mixed with ISONATE 143L. The temperature was slowly raised to 80 °C and maintained for 2-3 hours until the NCO content reached the theoretical value. Finally, the prepolymer was charged into a well-sealed container under nitrogen protection for further application.

[0169] Table 2 summarizes the formulation components and theoretical NCO for the four NCO-terminated prepolymers, with pure ISONATE 143L as the control.

[0170] [Table 2]

[0171] Part B was formulated according to the isocyanate components (Table 2) and summarized in Table 3.

[0172] [Table 3]

[0173] Table 3 shows that the tack-free time was very short when the aromatic isocyanate was not modified with dimer fatty acid-based polyester polyol (Example A). When the dimer fatty acid-based polyester polyol was replaced with castor oil or incorporated with a phosphoric acid-modified polyol, the tack-free time was too short to meet the requirements.

[0174] The adhesive formulations are summarized in Table 4a, along with details of Part A and corresponding examples of Part B. Adhesive applicators are often available with a volumetric mix ratio of 1:1. To ensure complete cure of the adhesive, the stoichiometry of 2K PU adhesives is typically set in the range of 1.15 to 1.35. Therefore, the formulations are designed to meet these requirements. The volumetric mix ratios and stoichiometry were calculated and listed in Table 4a.

[0175] [Table 4]

[0176] [Table 5]

[0177] The isocyanate prepolymer of Part B was prepared according to the following procedure. Step 1: Add the NCO-terminated prepolymer to a vessel, then add the other liquid ingredients (DINP, IPPP, Z-6040). Step 2 Apply vacuum and mix at medium agitation speed for 30 minutes. Step 3: Add the silica 606 to the container and mix the powders, then apply a vacuum and mix at high speed for 30 minutes. Step 4: Add the fumed silica to the container and mix the powders, then apply a vacuum and mix at high speed for 1 hour. Step 5 Set the temperature bath to 80°C and continue mixing at medium to slow agitation speed for 30 minutes to maintain the temperature. Step 6 Set the temperature bath to 20°C and cool to below 40°C.

[0178] Tack-free time was tested according to the following procedure. Place 10 g of Part B in a 50 ml plastic beaker and place the beaker in an oven at 45% humidity and 23°C. Begin recording the time. Periodically remove the beaker and gently touch the surface of Part B with a plastic stick. As the reaction between Part B and moisture progresses, the surface viscosity increases. Stop recording the time when the surface of Part B is no longer sticky. Record this period as the tack-free time of Part B.

[0179] The polyol mixture for Part A was prepared according to the following procedure. Step 1: Castor oil, OH-terminated prepolymer, CP450, and BDO are placed in a container, followed by the addition of the phosphoric acid-modified polyol. Step 2 Heat to 80°C, apply vacuum and mix at medium agitation speed for 1 hour to degas. Step 3: Add the silica 606 to the container and mix the powders, then apply a vacuum and mix at high speed for 15 minutes. Step 4: Add the molecular sieve 3A to the container and mix the powder, then apply vacuum and mix at high speed for 15 minutes. Step 5 Add AEROSIL R974 to the container and mix the powder, then apply vacuum and mix at high speed for 1 hour. Step 6 Cool to below 40°C.

[0180] Test Method: The lap joint test coupons were prepared using the following procedure. 1. A substrate was made of 3003 aluminum alloy with dimensions of 25mm x 12.5mm. 2. Clean the substrate surface by wiping it with ethanol. 3. Use pressure sensitive tape to mask off a 25mm x 12mm adhesive area. 4. Mix adhesive parts A and B together and place in a speed mixer at 1000 rpm for 1 minute to mix thoroughly. 5. Apply 0.5g to 1.5g of adhesive to the bonding area of ​​the substrate. Insert two 0.2mm diameter copper wires to adjust the thickness of the adhesive. 6. Place another masked substrate along the length of the base, with the same adhesive areas touching head to head. Line up the two clippers and press the adhesive surfaces together to secure them in place. 7. Allow the adhesive to cure at 25°C for 7 days.

[0181] Butt joint test coupons were prepared using the following procedure. 1. A substrate was made of 3003 aluminum alloy with dimensions of 60 mm height and 15 mm diameter. 2. Clean the substrate surface by wiping it with ethanol. 3. Mix adhesive parts A and B together and place in a speed mixer at 1000 rpm for 1 minute to mix thoroughly. 4. Apply 0.5g to 1g of adhesive to the flat surface of the substrate. Insert two 0.25mm diameter copper wires into the adhesive to adjust the thickness. 5. Stack the cleaned substrates together with the flat surfaces bonded together. Keep the stacked substrates vertical so that the bonded surfaces are always held in place by gravity. 6. Allow the adhesive to cure at 25°C for 7 days.

[0182] The test coupons were assembled on the fixtures of an Instron testing machine (model: Instron 5566) and tested for shear strength of the lap joints and tensile strength of the butt joints at a strain rate of 5 mm / min.

Claims

1. A) a polyol component comprising a hydrophobic polyol and a phosphate-functional adhesion promoter; B) a two-part adhesive composition comprising the reaction product of (I) an isocyanate monomer and (II) an isocyanate component comprising the reaction product of a dimer acid polyester polyol.

2. The dimer acid polyester polyol component is A) a dimer acid; 10. The two-part adhesive composition of claim 1, comprising the reaction product of a reaction mixture comprising: B) a polyol; and C) a polyol.

3. The dimer acid polyester polyol component is A) a dimer acid; B) a polyol; and C) a dicarboxylic acid.

4. 10. The two-part adhesive composition of claim 1, wherein the hydrophobic polyol is castor oil.

5. 10. The two-part adhesive composition of claim 1, wherein the phosphoric acid functional adhesion promoter is a phosphoric acid modified polyol.

6. 2. The two-component adhesive composition of claim 1, having an NCO index of 1.15 to 1.

30.

7. 3. The two-component adhesive composition of claim 2, wherein the dimer acid has the following structure (A), structure (B), structure (C), structure (D), or structure (E): 【Chemical 1】 【Chemistry 2】

8. A multi-layer structure, a first substrate; a second substrate; and an adhesive layer between the first substrate and the second substrate, the adhesive layer being formed from the two-part adhesive composition of claim 1.

9. 9. The multilayer structure of claim 8, wherein the first substrate and the second substrate are each a film comprising a layer containing a component selected from an ethylene-based polymer (PE), a propylene-based polymer (PP), a polyamide (such as nylon), a polyester, an ethylene-vinyl alcohol (EVOH) copolymer, a polyethylene terephthalate (PET), an ethylene-vinyl acrylate (EVA) copolymer, an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-butyl acrylate copolymer, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer, an ionomer of ethylene-acrylic acid, an ionomer of methacrylic acid, a maleic anhydride-grafted ethylene-based polymer, a polylactic acid (PLA), a polystyrene, a metal foil, cellulose, cellophane, a nonwoven fabric, and combinations thereof.

10. 9. The multilayer structure of claim 8, wherein the first substrate is a monolayer film having a single layer that is a metal foil layer, and the second substrate is a monolayer film having a single layer that is a metal foil layer.

11. 1. A method of forming a two-part adhesive composition, comprising: A) providing a polyol component A) comprising a hydrophobic polyol and a phosphate-functional adhesion promoter; B) providing an isocyanate component B) comprising the reaction product of an isocyanate monomer and a dimer acid polyester polyol; (C) reacting said isocyanate component B) with said polyol component A) to form said two-part adhesive composition.

12. Use of the two-component adhesive composition of claim 1 in a battery pack.

Images