HK1198045A

HK1198045A - Structural adhesive compositions

Info

Publication number: HK1198045A
Application number: HK14110668.4A
Authority: HK
Inventors: U．C．德赛; 赵天杰; 中岛将行; K．G．拉古内森
Original assignee: Ppg工业俄亥俄公司
Priority date: 2011-12-09
Filing date: 2012-12-07
Publication date: 2015-03-06

Description

Structural adhesive composition

Technical Field

The present invention relates to structural adhesive compositions, and more particularly, to 1K and 2K structural adhesive compositions.

Background information

Structural adhesives are used in a wide variety of applications to bond two or more substrate materials together. For example, structural adhesives may be used to bond wind turbine blades together or to bond automotive structural components together.

The present invention relates to one-component (1K) and two-component (2K) adhesive compositions that provide sufficient bond strength, are easy to apply, and, where applicable, have a sufficiently long shelf life for bonding substrate materials together.

Disclosure of Invention

One embodiment of the present invention discloses a composition comprising (a) a first component comprising (i) an epoxy adduct that is a reaction product of reactants comprising a first epoxy compound, a polyol, and an anhydride and/or diacid; (b) rubber particles and/or grapheme carbon particles having a core/shell structure; and (c) a second component that chemically reacts with the first component under ambient or slightly heated conditions.

Another embodiment of the present invention discloses a composition comprising (a) an epoxy terminated toughener; and (b) a heat-activated latent curing agent; and optionally (c) rubber particles having a core/shell structure and/or grapheme carbon particles; (d) epoxy/CTBN adducts; and/or (e) an epoxy/dimer acid adduct.

Drawings

FIG. 1 is a perspective view of a Teflon template assembly used to evaluate the tensile properties of a structural adhesive according to an exemplary embodiment of the present invention.

Detailed Description

In the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification and claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of "1 to 10" is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, i.e., having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

In this application, the use of the singular includes the plural and plural encompasses singular, unless expressly stated otherwise. In addition, in this application, the use of "or" means "and/or" unless explicitly stated otherwise, even though "and/or" may be explicitly used in certain instances.

As noted above, the present invention generally discloses 1K ("one-part") and 2K ("two-part") structural adhesive compositions for bonding two substrate materials together for a wide variety of potential applications in which the bond between the substrate materials provides specific mechanical properties relating to elongation, tensile strength, lap shear strength, T-peel strength, modulus or impact peel strength. The structural adhesive is applied to one or both of the materials to be joined. The sheets are aligned and pressure and spacers may be added to control the bond thickness. For 2K binders, curing is initiated by mixing the components together at ambient or slightly heated temperatures. In contrast to 1K adhesives, the adhesives are cured using an external source such as an oven (or other heating means) or by using actinic radiation (UV light, etc.).

Suitable substrate materials that may be bonded by the structural adhesive composition include, but are not limited to, materials such as metals or metal alloys, natural materials such as wood, polymeric materials such as hard plastics, or composite materials. The structural adhesives of the present invention are particularly useful in various automotive applications and in wind turbine technology.

As mentioned above, the structural adhesive composition of the invention is suitable for joining two half-shells of a wind turbine blade. In this application, for a 2K adhesive, the mixed adhesive composition is applied along the edges of one or both half shells of a wind turbine blade. The half shells are then pressed together and the 2K adhesive is allowed to cure for many hours under ambient or slightly heated conditions. A thermal cover (about 70 ℃) may be applied to the half shells to assist the curing process. In contrast, for 1K binders, the curing process is accomplished using an oven or a source of actinic radiation as opposed to systems in which the components are cured essentially by mixing.

The half shells or other parts of the wind turbine blade may be formed from metal, such as aluminium, metal alloys, such as steel, wood, such as raft wood, polymeric materials, such as hard plastics, or composite materials, such as fibre reinforced plastics. In one embodiment, the half shell is formed from a fiberglass composite or a carbon fiber composite.

The 2K structural adhesive of the present invention is formed from two chemical components (i.e., a first component and a second component) that are mixed just prior to use. In certain embodiments, the first component (i.e., the epoxy component) comprises an epoxy adduct and another epoxy compound, or a second epoxy compound. In certain embodiments, the second component comprises a curing component that reacts with the first component to form a bond that provides desirable bonding characteristics to the substrate to which it is applied. In certain embodiments, the curing component is an amine compound, although other curing components, such as sulfide curing components, may alternatively be used.

The equivalent ratio of amine to epoxy in the adhesive composition may be about 0.5: 1 to about 1.5: 1, e.g. 1.0: 1-1.25: 1. in certain embodiments, the equivalent ratio of amine to epoxy is slightly higher than 1: 1. as described herein, the equivalents of epoxy used in calculating the epoxy equivalent ratio is based on the epoxy equivalents of the first component, and the equivalents of amine used in calculating the amine equivalent ratio is based on the Amine Hydrogen Equivalents (AHEW) of the second component.

In one embodiment, the epoxy adduct is formed as a reaction product of reactants comprising a first epoxy compound, a polyol, and an anhydride.

In another embodiment, the epoxy adduct is formed as a reaction product of reactants comprising a first epoxy compound, a polyol, and a diacid.

In yet another embodiment, the epoxy adduct is formed as a reaction product of reactants comprising a first epoxy compound, a polyol, an anhydride, and a diacid.

In these embodiments, the epoxy adduct comprises 3 to 50 weight percent, such as 3 to 25 weight percent, of the first component and the second epoxy compound comprises 50 to 97 weight percent, such as 75 to 97 weight percent, of the first component.

Useful first epoxy compounds that can be used to form the epoxy adduct include polyepoxides. Suitable polyepoxides include the polyglycidyl ethers of bisphenol A, for example828 and 1001 epoxy resins, and bisphenol F diepoxides, e.g.862 commercially available from Hexion Specialty Chemicals, Inc. Other useful polyepoxides include polyglycidyl ethers of polyhydric alcohols, polyglycidyl esters of polycarboxylic acids, polyepoxides derived from the epoxidation of an ethylenically unsaturated cycloaliphatic compound, polyepoxides containing oxyalkylene groups in the epoxy molecule, and epoxy novolac resins. Still other non-limiting first epoxy compounds include epoxidized bisphenol A novolac, epoxidized phenolic novolac, epoxidized cresol novolac, and triglycidyl-p-aminophenol bismaleimide.

Useful polyols that can be used to form the epoxy adduct include diols, triols, tetrols and higher functional polyols. The polyols may be based on polyether chains derived from ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, and the like, and mixtures thereof. The polyol may also be based on a ring-opening polymerized polyester chain derived from caprolactone. Suitable polyols may also include polyether polyols, polyurethane polyols, polyurea polyols, acrylic polyols, polyester polyols, polybutadiene polyols, hydrogenated polybutadiene polyols, polycarbonate polyols, polysiloxane polyols, and combinations thereof. Polyamines corresponding to polyols may also be used and in this case will form amides with acids and anhydrides rather than carboxylic acid esters.

Suitable diols which can be used to form the epoxy adduct are those having a hydroxyl equivalent weight of from 30 to 1000. Exemplary diols having a hydroxyl equivalent weight of 30 to 1000 are included under the trade nameDiols sold under the market, comprising250, available from Invista. Other exemplary diols having a hydroxyl equivalent weight of 30 to 1000 include ethylene glycol and its polyether diol, propylene glycol and its polyether diol, butylene glycol and its polyether diol, hexylene glycol and its polyether diol, polyester diols synthesized by ring opening polymerization of caprolactone, and urethane diols synthesized by reacting cyclic carbonates with diamines. Combinations of these diols and polyether diols derived from combinations of the different diols described above may also be used. Dimer diols may also be used, including under the trade nameAnd Solvermol^TMThose commercially available from Cognis Corporation are listed below.

Can be used in the trade markPolytetrahydrofuranyl polyols sold under the name of650, from Invista. In addition, the method can also be used for the trade mark nameAnddimer diol-based polyols, commercially available from Cognis Corporation, or bio-based polyols, such as the tetrafunctional polyol agrol4.0, commercially available from BioBased Technologies.

Anhydride compounds used to functionalize the polyol with acid groups include hexahydrophthalic anhydride and its derivatives (e.g., methylhexahydrophthalic anhydride); phthalic anhydride and its derivatives (e.g., methylphthalic anhydride); maleic anhydride; succinic anhydride; trimellitic anhydride; pyrotrimellitic dianhydride (PMDA); 3,3 ', 4, 4' -Oxydiphthalic Dianhydride (ODPA); 3,3 ', 4, 4' -benzophenonetetracarboxylic dianhydride (BTDA); and 4, 4' -diphthalic acid (hexafluoroisopropylidene) anhydride (6 FDA). Diacid compounds useful for functionalizing the polyol with acid groups include phthalic acid and its derivatives (e.g., methylphthalic acid), hexahydrophthalic acid and its derivatives (e.g., methylhexahydrophthalic acid), maleic acid, succinic acid, adipic acid, and the like. Any diacid and anhydride may be used; anhydrides are preferred.

In one embodiment, the polyol comprises a diol, the anhydride and/or diacid comprises a monoanhydride or diacid, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of diol, monoanhydride (or diacid), and diepoxy compound in the epoxy adduct can be 0.5: 0.8: 1.0-0.5: 1.0: 6.0.

in another embodiment, the polyol comprises a diol, the anhydride and/or diacid comprises a monoanhydride or diacid, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of diol, monoanhydride (or diacid), and diepoxy compound in the epoxy adduct can be 0.5: 0.8: 0.6-0.5: 1.0: 6.0.

in another embodiment, the second epoxy compound of the first component is a diepoxide compound having an epoxy equivalent weight of from about 150 to about 1000. Suitable diepoxides having an epoxy equivalent weight of about 150 to about 1000 include polyglycidyl ethers of bisphenol A, for example828 and 1001 epoxy resins, and bisphenol F diepoxides, e.g.862 commercially available from Hexion Specialty Chemicals, Inc.

In another embodiment, the second epoxy compound of the first component is a diepoxide compound or a higher functional epoxide (collectively "polyepoxides"), including polyglycidyl ethers of polyhydric alcohols, polyglycidyl esters of polycarboxylic acids, polyepoxides derived from the epoxidation of ethylenically unsaturated cycloaliphatic compounds, polyepoxides containing oxyalkylene groups in the epoxy molecule, and epoxy novolac resins.

Still other non-limiting second epoxy compounds include epoxidized bisphenol A novolac, epoxidized phenolic novolac, epoxidized cresol novolac, and triglycidyl-p-aminophenol bismaleimide.

In another embodiment, the second epoxy compound of the first component comprises an epoxy-dimer acid adduct. The epoxy-dimer acid adduct may be used as a composition comprising a diepoxide compound (e.g., bisphenol A epoxy compound) and a dimer acid (e.g., C)₃₆Dimer acid) is formed.

In another embodiment, the second epoxy compound of the first component comprises an epoxy-modified carboxyl-terminated butadiene-acrylonitrile copolymer.

Useful amine compounds that can be used include primary amines, secondary amines, tertiary amines, and combinations thereof. Useful amine compounds that can be used include diamines, triamines, tetramines and higher functional polyamines.

Suitable primary amines include alkyldiamines such as 1, 2-diaminoethane, 1, 3-diaminopropane, 1, 4-diaminobutane, neopentyldiamine, 1, 8-diaminooctane, 1, 10-diaminodecane, 1, 12-diaminododecane, and the like; 1, 5-diamino-3-oxapentane, diethylene-triamine, triethylene tetramine, tetraethylene pentamine, and the like; alicyclic diamines such as 1, 2-bis (aminomethyl) cyclohexane, 1, 3-bis (aminomethyl) cyclohexane, 1, 4-bis (aminomethyl) cyclohexane, bis (aminomethyl) norbornane and the like; aromatic alkyldiamines such as 1, 3-bis (aminomethyl) benzene (m-xylylenediamine) and 1, 4-bis (aminomethyl) benzene (p-xylylenediamine) and their reaction products with epichlorohydrin such as Gaskamine328 and the like; amine-terminated polyethylene glycols such as the Jeffamine ED series of huntsman corporation and amine-terminated polypropylene glycols such as the Jeffamine D series of huntsman corporation; and amine-terminated polytetrahydrofurans such as the huntsman jeffamine EDR series. Primary amines having a functionality greater than 2 include, for example, the Jeffamine T series, available from Huntsman Corporation, which is an amine-terminated propoxylated trimethylolpropane or glycerol and aminated propoxylated pentaerythritol.

Still other amines that may be used include isophoronediamine, methylenediamine, 4, 8-diamino-tricyclo [5.2.1.0] decane and N-aminoethylpiperazine.

In certain embodiments, the amine compound comprises triethylenetetramine (TETA), isophoronediamine, 1, 3-bis (aminomethyl) cyclohexane, and polypropylene oxide based polyetheramines.

In certain embodiments, the polypropylene oxide based polyetheramine comprises the Jeffamine series product from Huntsman Chemical of houston, texas. Jeffamine series products are polyetheramines characterized by repeating oxypropylene units in their respective structures.

One exemplary class of Jeffamine products, the so-called "Jeffamine D series of products, are amine-terminated PPG (propylene glycol), having the following representative structure (formula (I)):

wherein x is 2 to 70.

In certain embodiments, Jeffamine D-230 is one of the D series products used. Jeffamine D-230 has an average molecular weight of about 230 (where x is 2.5) and an Amine Hydrogen Equivalent Weight (AHEW) of about 60. Other exemplary jeffamine d series products according to formula (I) that can be used include those where x is 2.5-68.

Another series of polypropylene oxide-based polyetheramines which can be used are predominantly tetrafunctional primary amines having a number average molecular weight of 200-2000 and more preferably 600-700 and an AHEW of greater than 60 and more preferably 70-90. Jeffamine XTJ-616 is one such polyoxypropylene polyetheramine that can be used in the present invention. Jeffamine XTJ-616 has a number average molecular weight of about 660 and an AHEW of 83.

Higher-grade AHEW amine compounds such as Jeffamine XTJ-616 and Jeffamine D-230 may be particularly useful in 2K binder compositions where longer shelf life is desired. Conventional tetraamines with lower AHEWS, such as triethylenetetramine, have a comparatively significantly shorter shelf life. The present invention thus provides a way to manipulate shelf life with tetrafunctional amines such as Jeffamine XTJ-616.

In yet another embodiment, the reinforcing filler may be added to the binder composition as part of the first component or as part of the second component, or both.

Useful reinforcing fillers that can be incorporated into the binder composition to provide improved mechanical properties include fibrous materials such as glass fibers, titanium dioxide fibers, whisker-type calcium carbonate (aragonite), and carbon fibers (which include graphite and carbon nanotubes). Additionally, glass fibers ground to 5 microns or wider and to 50 microns or longer may also provide additional tensile strength. More preferably, glass fibers ground to 5 microns or more and to 100-300 microns in length are used. Preferably, such reinforcing fillers, if used, constitute from 0.5 to 25% by weight of the binder composition.

In yet another embodiment, fillers, thixotropic agents, colorants, color imparting agents and other materials may be added to the first or second components of the binder composition.

Useful thixotropic agents that may be used include untreated fumed silica and treated fumed silica, castor wax, clays and organoclays. In addition, fibres, e.g. synthetic fibres such asFiber andfibers, acrylic fibers and engineered cellulose fibers may also be used.

Useful colorants or color-imparting agents may include iron red pigments, titanium dioxide, calcium carbonate and phthalocyanine blue.

Useful fillers that may be used with the thixotropic agent may include inorganic fillers such as inorganic clays or silica.

In yet another embodiment, if desired, a catalyst may be incorporated into the binder composition, preferably as part of the second component, to promote the reaction of the epoxide groups of the first component and the amine groups of the second component.

Useful catalysts that may be incorporated into the binder composition include those available from air productsProducts and products sold as "accelerators" from Huntsman Corporation. One exemplary catalyst is a piperazinyl accelerator 399 (AHEW: 145), available from Huntsman Corporation. When used, such catalysts comprise 0 to about 10 weight percent of the total binder composition.

In addition, the catalytic effect can be determined by the equivalence ratio of 1: 1 from the first component and an amine compound from the second component. An example of such a product isAndobtained from Mitsubishi Gas Chemical Corporation.

In certain embodiments, rubber particles having a core/shell structure may be included in the 2K structural binder formulation.

Suitable core-shell rubber particles include butadiene rubber; but other synthetic rubbers may be used; such as styrene-butadiene and acrylonitrile-butadiene, and the like. The type of synthetic rubber and the rubber concentration should not be limited as long as the particle size falls within the specified range shown below.

In certain embodiments, the average particle size of the rubber particles may be about 0.02 to 500 microns (20nm to 500000 nm).

In certain embodiments, the core/shell rubber particles are included in an epoxy carrier resin for incorporation into a 2K adhesive composition. Suitable finely divided core-shell rubber particles having an average particle size of from 50nm to 250nm are master batches in epoxy resins, such as aromatic epoxides, phenolic novolac epoxy resins, bisphenol a and bisphenol F diepoxides and aliphatic epoxides, which comprise cycloaliphatic epoxides in concentrations of from 20 to 40% by weight. Suitable epoxy resins may also include mixtures of epoxy resins.

Exemplary non-limiting commercially available core/shell rubber particle products (which use poly (butadiene) rubber particles with an average particle size of 100nm, which can be used in 2K binder compositions) include Kane Ace MX136 (a core-shell poly (butadiene) rubber dispersion (25%) in bisphenol F), Kane Ace MX153 (a dispersion in bisphenol F)828 core-shell poly (butadiene) rubber dispersion (33%), Kane Ace MX257 (a core-shell poly (butadiene) rubber dispersion in bisphenol a (37%)), and Kane Ace MX267 (a core-shell poly (butadiene) rubber dispersion in bisphenol F (37%)), each available from Kaneka Texas Corporation.

Exemplary non-limiting commercially available core/shell rubber particle products (which use styrene-butadiene rubber particles with an average particle size of 100nm, which can be used in 2K binder compositions) include Kane Ace MX113 (a core-shell styrene-butadiene rubber dispersion in low viscosity bisphenol a (33%)), Kane Ace MX125 (a core-shell styrene-butadiene rubber dispersion in bisphenol a (25%)), Kane Ace MX215 (a core-shell styrene-butadiene rubber dispersion in novolac epoxy of DEN-438 phenol (25%)), and Kane AceMX416 (a core-shell styrene-butadiene rubber dispersion in MY-721 multifunctional epoxy (25%)), Kane Ace MX451 (a core-shell styrene-butadiene rubber dispersion in MY-0510 multifunctional epoxy (25%)), kane Ace MX551 (a core-shell styrene-butadiene rubber dispersion in cycloaliphatic epoxy of Synasia21 (25%)), Kane Ace MX715 (a core-shell styrene-butadiene rubber dispersion in polypropylene glycol (MW400) (25%)), each available from Kaneka Texas Corporation.

In certain embodiments, the amount of core/shell rubber particles included in the 2K binder formulation is from 0.1 to 10 weight percent, such as from 0.5 to 5 weight percent, based on the total weight of the 2K coating composition.

In still other embodiments, grapheme carbon particles may be included in a 2K structural binder formulation.

As defined herein, graphene is an allotrope of carbon, the structure of which is sp²A one atom thick plate of bonded carbon atoms densely packed in the honeycomb lattice. Graphene is stable, chemically inert and mechanically robust under ambient conditions. As used herein, the term "graphenic carbon particles" refers to carbon particles having sp-containing groups²One atom thick flat plate of bonded carbon atoms, which is densely packed in the honeycomb lattice. Likewise, the term "grapheme carbon particles" includes one-layer thick plates (i.e., graphene) and multi-layer thick plates. The average number of layers of the stack may be less than 100, for example less than 50. In certain embodiments, the average number of stacked layers is 30 or less. The grapheme carbon particles may be substantially flat, but at least a portion of the flat sheet may be substantially curved, curled, or wrinkledAnd (4) texturing. The particles typically do not have a spheroidal or equiaxed morphology.

In certain embodiments, the graphenic carbon particles used in the invention have a thickness (measured in a direction perpendicular to the layer of carbon atoms) of no greater than 10 nanometers, such as no greater than 5 nanometers, or in certain embodiments no greater than 3 or 1 nanometer. In certain embodiments, the grapheme carbon particles may be from 1 atomic layer to 10, 20, or 30 atomic layers thick, or greater. The grapheme carbon particles may be provided in the form of ultrafine flakes, platelets, or flat sheets having a particle size of greater than 3: 1, e.g. greater than 10: 1, relatively high aspect ratio.

In certain embodiments, the grapheme carbon particles are in an epoxy carrier resin such as828 medium roll mill for incorporation into the 2K binder composition. In an exemplary embodiment, the grapheme carbon particle/added epoxy resin masterbatch is formed by milling grapheme carbon particles in epoxy resin at a concentration of 10 weight percent or greater. The dispersion method includes typical pigment grinding mills such as three-roll mills, Eiger mills, Netsch/Premier mills, and the like.

An exemplary graphene carbon particulate material that may be used in a 2K binder formulation is XGSciences graphene grade C, which has a surface area of 750m²(iv) g, an average thickness of about 2 nm and an average diameter of less than 2 μm.

In certain embodiments, the amount of grapheme carbon particles included in the 2K binder formulation is sufficient to provide an increased tensile modulus while maintaining the glass transition temperature as compared to formulations that do not include grapheme carbon particles.

In certain embodiments, the amount of grapheme carbon particles included in the 2K binder formulation is from about 0.5 to 25 weight percent based on the total weight of the 2K coating composition

As also noted above, in certain embodiments, the 1K structural binders of the present invention comprise: (a) an epoxy-terminated toughener; and (b) a heat-activated latent curing agent. In certain other embodiments, the 1K structural adhesive may further comprise one or more of the following components: (c) epoxy/CTBN (carboxyl terminated butadiene acrylonitrile polymer) adducts; (d) an epoxy/dimer acid adduct; (e) rubber particles having a core/shell structure; and (f) grapheme carbon particles. Each of the components (a) - (e) is further described below.

In certain embodiments, (a) the epoxy-terminated toughener is formed as a reaction product of reactants comprising a first epoxy compound, a polyol, and an anhydride and/or a diacid (i.e., the anhydride, the diacid, or both the anhydride and the diacid can be part of the reaction product).

Useful epoxy compounds that may be used include polyepoxides. Suitable polyepoxides include the polyglycidyl ethers of bisphenol A, for example828 and 1001 epoxy resins, and bisphenol F diepoxides, e.g.862 commercially available from Hexion specialty chemicals, Inc. Other useful polyepoxides include polyglycidyl ethers of polyhydric alcohols, polyglycidyl esters of polycarboxylic acids, polyepoxides derived from the epoxidation of an ethylenically unsaturated cycloaliphatic compound, polyepoxides containing oxyalkylene groups in the epoxy molecule, and epoxy novolac resins. Still other non-limiting first epoxy compounds include epoxidized bisphenol A novolac, epoxidized phenolic novolac, epoxidized cresol novolac, and triglycidyl-p-aminophenol bismaleimide.

Useful polyols that may be used include diols, triols, tetrols and higher functional polyols. The polyols may be based on polyether chains derived from ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, and the like, and mixtures thereof. The polyol may also be based on a ring-opening polymerized polyester chain derived from caprolactone. Suitable polyols may also include polyether polyols, polyurethane polyols, polyurea polyols, acrylic polyols, polyester polyols, polybutadiene polyols, hydrogenated polybutadiene polyols, polycarbonate polyols, polysiloxane polyols, and combinations thereof. Polyamines corresponding to polyols may also be used and in this case will form amides with acids and anhydrides rather than carboxylic acid esters.

Suitable diols which can be used are those having a hydroxyl equivalent weight of from 30 to 1000. Exemplary diols having a hydroxyl equivalent weight of 30 to 1000 are included under the trade nameDiols sold under the market, comprising250, available from Invista. Other exemplary diols having a hydroxyl equivalent weight of 30 to 1000 include ethylene glycol and its polyether diol, propylene glycol and its polyether diol, butylene glycol and its polyether diol, hexylene glycol and its polyether diol, polyester diols synthesized by ring opening polymerization of caprolactone, and urethane diols synthesized by reacting cyclic carbonates with diamines. Combinations of these diols and polyether diols derived from combinations of the different diols described above may also be used. Dimer diols may also be used, including under the trade nameAnd Solvermol^TMThose commercially available from Cognis Corporation are listed below.

Useful anhydride compounds for functionalizing the polyol with acid groups include hexahydrophthalic anhydride and its derivatives (e.g., methylhexahydrophthalic anhydride); phthalic anhydride and its derivatives (e.g., methylphthalic anhydride); maleic anhydride; succinic anhydride; trimellitic anhydride; pyrotrimellitic dianhydride (PMDA); 3,3 ', 4, 4' -Oxydiphthalic Dianhydride (ODPA); 3,3 ', 4, 4' -benzophenonetetracarboxylic dianhydride (BTDA); and 4, 4' -diphthalic acid (hexafluoroisopropylidene) anhydride (6 FDA). Useful diacid compounds for functionalizing the polyol with acid groups include phthalic acid and its derivatives (e.g., methylphthalic acid), hexahydrophthalic acid and its derivatives (e.g., methylhexahydrophthalic acid), maleic acid, succinic acid, adipic acid, and the like. Any diacid and anhydride may be used; anhydrides are preferred.

In one embodiment, the polyol comprises a diol, the anhydride and/or diacid comprises a mono-anhydride or diacid, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of diol, mono-anhydride (or diacid), and diepoxy compound in the epoxy-terminated toughener can be 0.5: 0.8: 1.0-0.5: 1.0: 6.0.

in another embodiment, the polyol comprises a diol, the anhydride and/or diacid comprises a mono-anhydride or diacid, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of diol, mono-anhydride (or diacid), and diepoxy compound in the epoxy-terminated toughener can be 0.5: 0.8: 0.6-0.5: 1.0: 6.0.

in certain embodiments, (a) the epoxy-terminated toughener comprises the reaction product of reactants comprising an epoxy compound, an anhydride, and/or a diacid and caprolactone. In certain other embodiments, diamines and/or higher functional amines may be included in the reaction product in addition to the epoxy compound, caprolactone, and anhydride and/or diacid.

Suitable epoxy compounds that may be used to form the epoxy-terminated tougheners include epoxy-functional polymers, which may be saturated or unsaturated, cyclic or acyclic, aliphatic, alicyclic, aromatic or heterocyclic. The epoxy-functional polymer may have pendant or terminal hydroxyl groups, if desired. They may contain substituents such as halogen, hydroxyl and ether groups. One useful class of these materials includes polyepoxides containing epoxy polyethers obtained by reacting an epihalohydrin (e.g., epichlorohydrin or epibromohydrin) with a di-or polyhydric alcohol in the presence of a base. Suitable polyhydric alcohols include polyphenols such as resorcinol; catechol; hydroquinone; bis (4-hydroxyphenyl) -2, 2-propane, bisphenol a; bis (4-hydroxyphenyl) -1, 1-isobutane; 4, 4-dihydroxybenzophenone; bis (4-hydroxyphenol) -1, 1-ethane; bis (2-hydroxyphenyl) -methane and 1, 5-hydroxynaphthalene.

Frequently used polyepoxides include the polyglycidyl ethers of bisphenol A, for example828 epoxy resin, commercially available from Hexion Specialty Chemicals, Inc. has a number average molecular weight of about 400 and an epoxy equivalent weight of about 185-. Other useful polyepoxides include polyglycidyl ethers of other polyhydric alcohols, polyglycidyl esters of polycarboxylic acids, polyepoxides derived from the epoxidation of an ethylenically unsaturated cycloaliphatic compound, polyepoxides containing oxyalkylene groups in the epoxy molecule, epoxy novolac resins, and polyepoxides that are partially defunctionalized by carboxylic acids, alcohols, water, phenols, thiols, or other active hydrogen-containing compounds to produce hydroxyl-containing polymers.

Useful anhydride compounds that may be used include hexahydrophthalic anhydride and its derivatives (e.g., methylhexahydrophthalic anhydride); phthalic anhydride and its derivatives (e.g., methylphthalic anhydride); maleic anhydride; succinic anhydride; trimellitic anhydride; pyrotrimellitic dianhydride (PMDA); 3,3 ', 4, 4' -Oxydiphthalic Dianhydride (ODPA); 3,3 ', 4, 4' -benzophenonetetracarboxylic dianhydride (BTDA); and 4, 4' -diphthalic acid (hexafluoroisopropylidene) anhydride (6 FDA). Useful diacid compounds for functionalizing polyols with acid groups include phthalic acid and its derivatives (e.g., methylphthalic acid), hexahydrophthalic acid and its derivatives (e.g., methylhexahydrophthalic acid), maleic acid, succinic acid, adipic acid, and the like. Any diacid and anhydride may be used; anhydrides are preferred.

Useful caprolactones that can be used include caprolactone monomers, methyl, ethyl and propyl substituted caprolactone monomers, and polyester diols derived from caprolactone monomers. Exemplary polyester diols having molecular weights of about 400-Diols sold under the market, comprising2085, obtained from Perstorp.

Useful diamine or higher functional amine compounds that can be used to form the epoxy-terminated toughener include primary amines, secondary amines, tertiary amines, and combinations thereof. Useful amine compounds that can be used include diamines, triamines, tetramines and higher functional polyamines.

Suitable primary or higher functional amines that may be used include alkyldiamines such as 1, 2-diaminoethane, 1, 3-diaminopropane, 1, 4-diaminobutane, neopentyldiamine, 1, 8-diaminooctane, 1, 10-diaminodecane, 1, 12-diaminododecane, and the like; 1, 5-diamino-3-oxapentane, diethylene-triamine, triethylene tetramine, tetraethylene pentamine, and the like; alicyclic diamines such as 1, 2-bis (aminomethyl) cyclohexane, 1, 3-bis (aminomethyl) cyclohexane, 1, 4-bis (aminomethyl) cyclohexane, bis (aminomethyl) norbornane and the like; aromatic alkyldiamines such as 1, 3-bis (aminomethyl) benzene (m-xylylenediamine) and 1, 4-bis (aminomethyl) benzene (p-xylylenediamine) and their reaction products with epichlorohydrin such as Gaskamine328 and the like; amine-terminated polyethylene glycols such as the Jeffamine ED series of Huntsman Corporation and amine-terminated polypropylene glycols such as the Jeffamine D series of Huntsman Corporation; and amine-terminated polytetrahydrofurans such as the Huntsman Jeffamine EDR series. Primary amines having a functionality greater than 2 include, for example, the Jeffamine T series, available from Huntsman Corporation, which is an amine-terminated propoxylated trimethylolpropane or glycerol and aminated propoxylated pentaerythritol.

wherein x is 2 to 70.

In one embodiment, the caprolactone comprises caprolactone monomers, the anhydride and/or diacid comprises mono-or diacid, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of caprolactone monomers, mono-or diacid, and diepoxy compound in the epoxy-terminated toughener can be 0.5: 0.8: 1.0-0.5: 1.0: 6.0.

in one embodiment, the caprolactone comprises caprolactone monomers, the anhydride and/or diacid comprises mono-or diacid, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of caprolactone monomers, mono-or diacid, and diepoxy compound in the epoxy-terminated toughener can be 0.5: 0.8: 0.6-0.5: 1.0: 6.0.

in one embodiment, the caprolactone comprises caprolactone monomers, the anhydride and/or diacid comprises mono-or diacid, the diamine or higher functional amine comprises diamine, and the first epoxy compound comprises a diepoxy compound, wherein the molar ratio of caprolactone monomers, mono-anhydride (or diacid), diamine and diepoxy compound in the epoxy-terminated toughener can be 2: 1: 2: 2-3: 1: 3: 3.

in certain embodiments, (a) the epoxy-terminated toughener comprises the reaction product of reactants comprising an epoxy compound and a primary or secondary polyetheramine.

Suitable epoxy compounds that may be used to form the epoxy-terminated tougheners include epoxy-functional polymers, which may be saturated or unsaturated, cyclic or acyclic, aliphatic, alicyclic, aromatic or heterocyclic. The epoxy-functional polymer may have pendant or terminal hydroxyl groups, if desired. They may contain substituents such as halogen, hydroxyl and ether groups. One useful class of these materials includes polyepoxides containing epoxy polyethers obtained by reacting an epihalohydrin (e.g., epichlorohydrin or epibromohydrin) with a di-or polyhydric alcohol in the presence of a base. Suitable polyhydric alcohols include polyphenols such as resorcinol; catechol; hydroquinone; bis (4-hydroxyphenyl) -2, 2-propane, i.e., bisphenol a; bis (4-hydroxyphenyl) -1, 1-isobutane; 4, 4-dihydroxybenzophenone; bis (4-hydroxyphenol) -1, 1-ethane; bis (2-hydroxyphenyl) -methane and 1, 5-hydroxynaphthalene.

Frequently used polyepoxides include the polyglycidyl ethers of bisphenol A, for example828 epoxy resin, commercially available from Hexion Specialty Chemicals, Inc. and having a number average molecular weight of about 400 and epoxyThe equivalent weight is about 185 and 192. Other useful polyepoxides include polyglycidyl ethers of other polyhydric alcohols, polyglycidyl esters of polycarboxylic acids, polyepoxides derived from the epoxidation of an ethylenically unsaturated cycloaliphatic compound, polyepoxides containing oxyalkylene groups in the epoxy molecule, epoxy novolac resins, and polyepoxides that are partially defunctionalized by carboxylic acids, alcohols, water, phenols, thiols, or other active hydrogen-containing compounds to produce hydroxyl-containing polymers.

Useful primary and secondary polyetheramine compounds that can be used to form epoxy-terminated tougheners include amine-terminated polyethylene glycols such as the Huntsman Corporation Jeffamine ED series and amine-terminated polypropylene glycols such as the Huntsman Corporation Jeffamine D series; and amine-terminated polytetrahydrofurans such as the Huntsman Jeffamine EDR series. Primary amines having a functionality greater than 2 include, for example, the Jeffamine T series, available from huntsman corporation, which is an amine-terminated propoxylated trimethylolpropane or glycerol and aminated propoxylated pentaerythritol.

In one embodiment, the epoxy compound comprises a diepoxide, and the primary or secondary polyether amine comprises a difunctional amine, wherein the molar ratio of diepoxide to difunctional amine is 2: 0.2-2: 1.

in certain embodiments, the 1K structural adhesive may include from 2 to 40 weight percent, such as from 10 to 20 weight percent, of any of the above forms of (a) the epoxy-terminated toughener, based on the total weight of the 1K structural adhesive composition.

In still other related embodiments, (a) the epoxy-terminated toughener(s) can comprise a mixture of any two or more of the above epoxy-terminated tougheners, wherein the total weight percentage of the mixture of two or more epoxy-terminated tougheners comprises 2 to 40 weight percent, such as 10 to 20 weight percent, based on the total weight of the 1K structural adhesive composition.

In certain embodiments, heat-activated latent curing agents that may be used include guanidines, substituted ureas, melamine resins, guanamine derivatives, cyclic tertiary amines, aromatic amines, and/or mixtures thereof. The hardener may be included in the hardening reaction in stoichiometric amounts; but they may also be catalytically active. Examples of substituted guanidines are methylguanidine, dimethylguanidine, trimethylguanidine, tetramethylguanidine, methylisobiguanide, dimethylbiguanide, tetramethylbiguanide, hexamethylbiguanide, heptamethylisobiguanide and more particularly cyanoguanidine (dicyandiamide). Representative suitable guanamine derivatives which may be mentioned are alkylated benzoguanamine resins, benzoguanamine resins or methoxymethylethoxymethylbenzguanamine. In addition, catalytically active substituted ureas may also be used. Suitable catalytically active substituted ureas include p-chlorophenyl-N, N-dimethylurea, 3-phenyl-1, 1-dimethylurea (fenuron) or 3, 4-dichlorophenyl-N, N-dimethylurea.

In certain other embodiments, the heat-activated latent curing agent also or alternatively comprises dicyandiamide and 3, 4-dichlorophenyl-N, N-dimethylurea (also known as diuron).

In certain embodiments, the 1K structural adhesive may include 3 to 25 weight percent, such as 5 to 10 weight percent, of (b) a heat-activated latent curing agent, based on the total weight of the 1K structural adhesive composition.

As described above, in certain embodiments, the 1K structural adhesive composition may include (c) an epoxy/CTBN adduct. In certain embodiments, the CTBN liquid polymers undergo an addition esterification reaction with an epoxy resin, which allows them to act as elastomer modifiers to enhance impact strength, peel strength, and crack resistance.

Suitable epoxy compounds that can be used to form the epoxy/CTBN adduct include epoxy-functional polymers, which can be saturated or unsaturated, cyclic or acyclic, aliphatic, alicyclic, aromatic or heterocyclic. The epoxy-functional polymer may have pendant or terminal hydroxyl groups, if desired. They may contain substituents such as halogen, hydroxyl and ether groups. One useful class of these materials includes polyepoxides containing epoxy polyethers obtained by reacting an epihalohydrin (e.g., epichlorohydrin or epibromohydrin) with a di-or polyhydric alcohol in the presence of a base. Suitable polyhydric alcohols include polyphenols such as resorcinol; catechol; hydroquinone; bis (4-hydroxyphenyl) -2, 2-propane, bisphenol a; bis (4-hydroxyphenyl) -1, 1-isobutane; 4, 4-dihydroxybenzophenone; bis (4-hydroxyphenol) -1, 1-ethane; bis (2-hydroxyphenyl) -methane and 1, 5-hydroxynaphthalene.

In certain embodiments, at least a portion, often at least 5 weight percent, of the polyepoxide has been reacted with the carboxyl terminated butadiene acrylonitrile polymer. In certain of these embodiments, the acrylonitrile content of the carboxyl terminated butadiene acrylonitrile polymer is 10 to 26 weight percent. Suitable CTBN compounds (with acrylonitrile content of 10-26 wt%) that may be used include hypo 1300X8, hypo 1300X9, hypo 1300X13, hypo 1300X18 and hypo 1300X31, each available from Emerald Specialty Polymer, LLC of Akron, Ohio.

In certain other embodiments, the polyepoxide may be reacted with a mixture of different carboxyl terminated butadiene acrylonitrile polymers.

In certain embodiments, the CTBN used has a functionality of 1.6 to 2.4, and the epoxy compound reacts with the CTBN material in stoichiometric amounts to form an epoxy/CTBN adduct.

In certain embodiments, the epoxy/CTBN adduct comprises from about 1 to 20 weight percent, such as from 5 to 10 weight percent, of the total weight of the 1K structural adhesive composition.

As noted above, in certain embodiments, the 1K structural adhesive composition may include (d) an epoxy/dimer acid adduct. In certain embodiments, the epoxy/dimer acid adduct may be formed by reacting an epoxy compound with a dimer acid.

Suitable epoxy compounds that may be used to form the epoxy/dimer acid adduct include epoxy-functional polymers, which may be saturated or unsaturated, cyclic or acyclic, aliphatic, alicyclic, aromatic or heterocyclic. The epoxy-functional polymer may have pendant or terminal hydroxyl groups, if desired. They may contain substituents such as halogen, hydroxyl and ether groups. One useful class of these materials includes polyepoxides containing epoxy polyethers obtained by reacting an epihalohydrin (e.g., epichlorohydrin or epibromohydrin) with a di-or polyhydric alcohol in the presence of a base. Suitable polyhydric alcohols include polyphenols such as resorcinol; catechol; hydroquinone; bis (4-hydroxyphenyl) -2, 2-propane, bisphenol a; bis (4-hydroxyphenyl) -1, 1-isobutane; 4, 4-dihydroxybenzophenone; bis (4-hydroxyphenol) -1, 1-ethane; bis (2-hydroxyphenyl) -methane and 1, 5-hydroxynaphthalene.

Frequently used polyepoxides include the polyglycidyl ethers of bisphenol A, for example828 epoxy resin, commercially available from Hexion Specialty Chemicals, Inc. has a number average molecular weight of about 400 and an epoxy equivalent weight of about 185-. Other useful polyepoxides include polyglycidyl ethers of other polyhydric alcohols, polyglycidyl esters of polycarboxylic acids, polyepoxides derived from the epoxidation of an ethylenically unsaturated cycloaliphatic compound, polyepoxides containing oxyalkylene groups in the epoxy moleculeEpoxides, epoxy novolac resins, and polyepoxides that are partially defunctionalized by carboxylic acids, alcohols, water, phenols, thiols, or other active hydrogen-containing compounds to produce hydroxyl-containing polymers.

As defined herein, dimer acid or dimerized fatty acid is a dicarboxylic acid, which is typically prepared by dimerization of unsaturated fatty acids obtained from tall oil over a clay catalyst. Dimer acid typically comprises mainly dimerized stearic acid, which is referred to as C36 dimer acid. Suitable dimer acids for use in forming the epoxy/dimer acid adduct of the present invention may be obtained from Croda, inc.

In certain embodiments, the epoxy compound and dimer acid are reacted in stoichiometric amounts to form an epoxy/dimer acid adduct.

In certain embodiments, the epoxy/dimer acid adduct comprises from about 1 to 15 weight percent, such as from 2 to 7 weight percent, of the total weight of the 1K structural adhesive composition.

As noted above, in certain embodiments, the 1K structural adhesive composition may also include (e) rubber particles having a core/shell structure. Suitable core shell rubber particles for use in the 1K structural adhesive are the same as those described above in relation to the 2K adhesive formulation and therefore need not be described in further detail herein.

In certain embodiments, the 1K structural adhesive may include 0 to 75 wt%, such as 5 to 60 wt%, of (e) rubber particles having a core/shell structure, based on the total weight of the 1K structural adhesive composition.

As noted above, in certain embodiments, the 1K structural adhesive composition may also include (f) grapheme carbon particles. Suitable grapheme carbon particles for use in 1K structural adhesives are the same as those described above in relation to the 2K adhesive formulation and therefore need not be described in further detail herein.

In certain embodiments, the 1K structural binder may include 0 to 40 weight percent, such as 0.5 to 25 weight percent, (f) grapheme carbon particles, based on the total weight of the 1K structural binder composition.

In still other embodiments, the 1K structural binder formulation may also include an epoxy compound or resin that is not incorporated into or reacted as part of any of the above components (a) - (f), including epoxy functional polymers, which may be saturated or unsaturated, cyclic or acyclic, aliphatic, cycloaliphatic, aromatic or heterocyclic. The epoxy-functional polymer may have pendant or terminal hydroxyl groups, if desired. They may contain substituents such as halogen, hydroxyl and ether groups. One useful class of these materials includes polyepoxides containing epoxy polyethers obtained by reacting an epihalohydrin (e.g., epichlorohydrin or epibromohydrin) with a di-or polyhydric alcohol in the presence of a base. Suitable polyhydric alcohols include polyphenols such as resorcinol; catechol; hydroquinone; bis (4-hydroxyphenyl) -2, 2-propane, bisphenol a; bis (4-hydroxyphenyl) -1, 1-isobutane; 4, 4-dihydroxybenzophenone; bis (4-hydroxyphenol) -1, 1-ethane; bis (2-hydroxyphenyl) -methane and 1, 5-hydroxynaphthalene.

In yet another embodiment, a reinforcing filler may be added to the binder composition. Useful reinforcing fillers that can be incorporated into the binder composition to provide improved mechanical properties include fiber-containing materials such as glass fibers, titanium dioxide fibers, whisker-type calcium carbonate (aragonite), and carbon fibers (which include graphite and carbon nanotubes). Additionally, glass fibers ground to 5 microns or wider and to 50 microns or longer may also provide additional tensile strength. More preferably, glass fibers ground to 5 microns or more and to 100-300 microns in length are used. Preferably, such reinforcing fillers, if used, constitute from 0.5 to 25% by weight of the 1k binder composition.

In yet another embodiment, fillers, thixotropic agents, colorants, color imparting agents and other materials may be added to the 1K binder composition.

Exemplary other materials that may be used include, for example, calcium oxide and carbon black.

The following examples illustrate the invention and are not to be considered as limiting the invention to their details. All parts and percentages in the examples, as well as throughout the specification, are by weight unless otherwise indicated.

Examples

EXAMPLES 1-2K Binder compositions

Part A-synthetic polyether-polyester modified epoxy resins

A four-necked flask equipped with a condenser, thermometer, stirrer and nitrogen inlet was charged with 304.6 grams of hexahydrophthalic anhydride and 248.1 grams250. The mixture was heated to 100 ℃ under stirring and nitrogen atmosphere and the reaction mixture was held at 100 ℃ for 155 minutes. The reaction mixture was cooled to 60 ℃ and 1431.6 g of water were added828 and 15.0 grams of triphenylphosphine. The reaction mixture was heated to 110 ℃ and held at this temperature for 150 minutes. The mixture was then cooled to room temperature. The compound formed had 99.89% solids, an acid number of 0.2 and an epoxy equivalent of 380.7. The compounds formed are epoxy adducts of the first component of the 2K adhesive materials listed in part 1 of table 1 below.

Part B-evaluation of 2K binders with and without epoxy adduct; evaluation has a 2K binder with the same amine hydroxyl equivalent weight

The following examples compare 2K adhesive compositions without epoxy adduct (example 1) with those with epoxy adduct (examples 2-4). Table 1 lists the formulations of the first component (part 1) and the second component (part 2) of the 2K adhesive composition.

TABLE 1

Formulation of

Example 1

Example 2

Example 3

Example 4

Part 1

Section 2

Jeffamine D-230⁷	11.5	12	12	11.6
					Jeffamine XTJ-616⁸	5	5	-	2.5
Triethylenetetramine (TETA)⁹	-	-	2.3	-
					IPDA¹⁰	-	-	-	1.35
Accelerator 399¹¹	2.2	2.2	2.2	0.5
					Microglass9132³	1.5	6	8	4
Hakuenka CCR-S⁴	1	1.5	6	2
					Wacker HDK H17⁵	2.75	2.5	2	2.5
Tint AYD PC9298¹²	0.01	0.01	0.01	0.01

Results

Fatigue test (8MPa stress)

Period to failure	173532	>432000	337062	329371
					Period to failure	219062	>432000	>432000	>432000
Average	196297	>432000	337062	329371

1. Bisphenol A/epichlorohydrin resin from Huntsman advanced materials

2. Synthetic example, example 1 from part A

3. Silane-treated chopped glass fiber from Fibertec

4. Precipitated calcium carbonate from Shiraishi Kogyo Kaisha

5. Hydrophobic fumed silica, available from Wacker Chemie AG

ORG yellow color-imparting base material available from Elementis Specialties

7. Polyoxyalkyleneamines, available from Huntsman

8. Polyoxyalkyleneamines, available from Huntsman

9. Triethylenetetramine, available from Dow Chemical Co.

10. Isophoronediamine from Evonik AG

11. Mixture of alkanolamine/piperazine derivatives obtained from Huntsman

Phthlalo Blue pigment dispersion available from Elementis Specialties

Test method

In each example, the raw materials listed in table 1 were mixed using a high speed mixer DAC600FVZ (commercially available from FlackTek, Inc.). Ingredients 1 and 2 were mixed in part 1 at 2350 revolutions per minute ("RPM") for 2 minutes. Items 3-6 were then added and mixed for 1 minute at 2350 RPM. Items 7-11 were mixed for 1 minute in part 2, then the remaining ingredients were added and mixed for 1 minute in part 2. During this mixing process, the mixture was checked with a spatula and additional mixing time was given to ensure homogeneity when necessary. The final step of the mixing method included mixing the mixture with an air motor propeller in a vacuum sealed apparatus at a vacuum pressure of 28-30 inches for 5 minutes. After the final mixing step using an air motor screw, the adhesive composition was ready for testing.

Part 1 and part 2 targets are 2: mixing at a volume ratio of 1. In some cases, an appropriate weight ratio is determined for testing performance. For all examples, the amine to epoxy ratio was kept slightly above 1 to ensure complete reaction of the epoxy as shown in the results section of table 1. Part 1 and part 2, which were brought to weight ratios, were weighed and mixed in a DAC mixer at 2350RPM for 1 minute and immediately mixed under vacuum as described in the preceding paragraph. The mixed sample was then subjected to the following tests:

lap shear test: a 25mmX100mm sample was cut from a 6-layer unidirectional glass/epoxy laminate provided by MFG, inc. The sample was scored at one end at 12.5 mm. Adhesive was applied uniformly to the scored area of one of the samples for the bonded assembly of each. Uniformity of bond thickness was ensured by the addition of 1.0 + -0.5 mm glass spacer beads. Spacer beads were evenly spread onto the material covering no more than 5% of the total bonding area. Other test specimens are placed on the bonded areas and spring-loaded Clips such as Binder Clips from Office Max or Mini spring clamp from Home Depot are attached to one of the bonds to each edge to hold the assembly together during baking. Carefully align the parallel edges. Excess adhesive extruded was removed with a spatula before baking. The bonded assembly was given an open time of 15-30 minutes and baked at 70 degrees celsius for 6 hours, and after cooling, the remaining excess was sanded. The combination was allowed to settle at room temperature for at least 24 hours. The combination was inserted into a wedge-shaped clamp and partially pulled at a rate of 10mm/min in a tensile mode using an Instron model 5567. Lap shear strength was calculated by the Instron Blue Hill software package.

Mechanical properties of the free film: the same binder mixture was used to prepare a void-free dog bone free film by carefully skiving the material to avoid any air pockets. Figure 1 is an example of a teflon template for making five dog bone cavities. The template was glued to the solid teflon sheet with double sided tape prior to skiving the adhesive in the chamber. This assembly was given an open air time of 15-30 minutes and then baked at 70 ℃ for 6 hours. It was conditioned for at least 24 hours and then the dog bone-shaped free membrane was removed from the template. The actual thickness and width were recorded into the Instron5567 software. The dog bone was then inserted into a wedge-shaped clamp and pulled at a rate of 50 mm/min. Percent overhang, tensile strength and modulus were determined using the Instron Blue Hill software package. Alternatively, dog bone (dumbbell) shaped free films were prepared using the ISO527-1&2 method and die configuration anywhere shown in the table.

The load controlled lap shear fatigue test was performed using the same laminate and sample structure as in the previous paragraph. An automated system (which uses an Instron, servo controlled, hydraulically actuated, closed loop test set, and a personal computer with software, designed by WestmorelandMechanical Testing and Research, inc.). Each specimen was inserted into a wedge-acting clamp with a friction-retaining shim (thickness equal to the glass fiber base) and a bond wire to ensure axial loading. The test was conducted at room temperature, the R ratio of the sinusoidal waveform at 5Hz was 0.1 and the applied load was 8 MPa. The test lasted 432000 cycles or failed.

Part C-evaluation of shelf life of 2K binders with different amine hydroxyl equivalent weights:

table 2 shows a comparison of shelf life between propylene oxide based polyether tetraamines Jeffamine XTJ-616 and ethylene oxide based triethylenetetramine in similar formulations, wherein the amine/epoxy ratio was maintained between 1.03 and 1.05. The formulations and results are shown in table 2:

TABLE 2

Comparison of storage life

Formulation of

Example 5

Example 6

Part 1

Section 2

Jeffamine D-230⁷	12	12
			Jeffamine XTJ-616⁸	5
Triethylenetetramine (TETA)⁹	-	2.3
			Accelerator 399¹¹	0.5	0.5
Microglass9132³	5	7
			Hakuenka CCR-S⁴	3	6.64
Wacker HDK H17⁵	2.25	2.36
			Tint AYD PC9298¹²	0.01	0.01

Amine/epoxy ratio (2: 1 volume mix)	1.033	1.0464
			Storage life in minutes	174	63
Peak temperature (. degree. C.)	73	150
			Number of minutes to peak	239	83

In this experiment, the same amount of accelerator 399 was used for both formulations (examples 5 and 6), which also significantly affected shelf life. The shelf life is found to be significantly higher if the accelerator 399 is not present.

The shelf life is defined as the interval from the time when part 1 (epoxy component) and part 2 (amine component) are mixed to the time when the internal temperature of the binder reaches 50 ℃ in a mass of 415 ml. Part 1 and part 2 were mixed using a static mixer at a 2:1 volume ratio; the pc COX pneumatic dual applicator dispenses the mixed binder into 415ml labeled paper cups. The horizontal line and the initial time are recorded. The cup was immediately placed in a 25 ℃ water bath and a thermocouple was inserted into the center of the mixed binder mass. The time to storage life, peak temperature and time to peak temperature used to reach 50 ℃ were determined using a PC-based data logger to record the temperature per minute.

Part D-evaluation of 2K Binders with and without reinforcing Filler

In this experiment, the effect of adding glass fibers as reinforcing filler was compared in the sample formulations, as described in table 3:

examples 7 and 8 in Table 3 are a comparison of no and having a Microglass9132 (glass fiber bundles, average 220 micron length). The results show a significant increase in modulus when Microglass9132 is present.

TABLE 3

Effect of glass fibers on modulus Properties

Formulation of

Example 7

Example 8

Part 1

Section 2

Jeffamine D-230⁷	12	12
			Jeffamine XTJ-616⁸	5	5
Accelerator 399¹¹	2.2	2.2
			Microglass9132³	-	6
Hakuenka CCR-S⁴	1.5	1.5
			Wacker HDK H17⁵	2.5	2.5
Tint AYD PC9298¹²	0.01	0.01

Amine/epoxy ratio	1.032	1.032
			Lap shear strength (MPa)	27.7	24.4
Elongation (%)	4.8	3.5
			Tensile Strength (MPa)	66	61
Modulus (MPa)	2444	3211
			(data Range)	(2246-2673)	(3160-3269)

Part E-evaluation of 2K binder with graphenic carbon particles; evaluation of rubber particles 2K Binder systems (having a core-shell Structure)

The following examples compare a 2K binder composition with grapheme carbon particles (example 2) or a 2K binder composition with rubber particles having a core-shell structure (example 3). Table 4 shows the formulations of the first component (part 1) and the second component (part 2) for the 2K adhesive composition.

In the example using grapheme carbon particles, 20 grams are usedGraphene nanoplatelets (C-scale surface area 750m²Perg (obtained from XG Sciences Corporation)) was added to the pre-weighed amount828(180g, available from Hexion Specialty chemicals corporation) and the mixture was hand mixed in a laboratory glove box with a spatula. The mixture was then poured into a three-roll mill (manufactured by Kent Industrial u.s.a.inc.) and ground 6 times. The graphene is ground828 was poured from the mill and introduced into the mixture of example 2 below.

TABLE 4

Formulation of

Example 1

Example 2

Example 3

Part 1

Section 2

Jeffamine D-230⁵	10.35	10.35	10.35
				Jeffamine D-400¹⁶	4.46	4.46	4.46
Jeffamine XTJ-616⁸	2.92	2.92	2.92
				IPDA¹⁰	2.92	2.92	2.92
1, 3-bis (aminomethyl) cyclohexane¹⁷	1.04	1.04	1.04
				Triethylenetetramine (TETA)⁹	0.1	0.1	0.1
Accelerator 399¹¹	0.08	0.08	0.08
				Tint AYD PC9298¹²	0.01	0.01	0.01

Results

Amine/epoxy ratio

1.078

1.081

1.085

Mechanical Properties of the Binders measured according to ISO527-1&2

Elongation (%)	5.8	4.8	4.5
				Tensile Strength (MPa)	55.1	53.6	50.3
Modulus (MPa)	2663	4041	2616
				(data Range)	(2548-2861)	(3571-4505)	(2443-2958)

13.828/Terathane 650/hexahydrophthalic anhydride adduct; EEW412

14. Obtained from XG Sciences in828 graphene carbon particle dispersion (10%)

15. In that828 core-shell poly (butadiene) rubber Dispersion (33%) from Kaneka Texas Corporation

16. Polyoxyalkyleneamines, available from Huntsman

1, 3-bis (aminomethyl) cyclohexane (1,3-BAC), available from Mitsubishi gas chemical

Example 2-1K Binder composition

Part A-synthetic polyether-polyester modified epoxy resins

A four-necked flask equipped with a condenser, thermometer, stirrer and nitrogen inlet was charged with 321.3 grams of hexahydrophthalic anhydride and 677.7 grams of650. The mixture was heated to 100 ℃ under nitrogen atmosphere with stirring and the reaction was examined for exotherm. After the exotherm subsided, the temperature was set at 150 ℃ and maintained until the anhydride peaks of 1785 and 1855CM-1 disappeared. The reaction mixture was then cooled to 120 ℃ where 1646.0 grams of EPON828 and 15.0 grams of triphenylphosphine were added. The reaction mixture was maintained at 120 ℃ until the acid value was below 2.2, yielding a polyether-polyester modified epoxy resin having an epoxy equivalent weight of 412.

Part B-Synthesis of polycaprolactone diol-modified epoxy resin

To a suitable flask equipped with a reflux condenser and stirrer, 211.9 grams of hexahydrophthalic anhydride and 570.6 grams of polycaprolactone CAPA2085 were added. The mixture was heated to 100 ℃ while stirring and maintained until the acid number was below 125 and the IR anhydride peak at 1785-1855CM-1 disappeared. The reaction mixture was then cooled to ambient temperature and 221 grams of this derivative were charged to another flask equipped with a reflux condenser and stirrer. Mixing 310.6 g828 (bisphenol A epichlorohydrin) and 3.00 g of triphenylphosphine were added to this derivativeAnd heating the mixture to 110 ℃ while stirring. The heating jacket was removed when the exotherm temperature peak was at about 145 ℃ to allow the temperature to drop. The reaction temperature was then maintained at about 110 ℃ until the acid number of the mixture was below 2. The reaction mixture was then cooled to ambient temperature and stored. Number average molecular weight (M) of the resulting polycaprolactone diol-modified epoxy resin_n) Is 2042 and an Epoxy Equivalent Weight (EEW) of 435.

Partially C-synthetic amide-polyether-polyester modified epoxy resins

323.5 grams of Jeffamine D400 and 167.6 grams of E-caprolactone were charged into a suitable flask equipped with a reflux condenser and a stirrer. The mixture was heated to 150 ℃ while stirring until the MEQ amine value was below 0.75 MEQ/gm. The mixture was then cooled to 60 ℃ where 226.5 grams of hexahydrophthalic anhydride was added to the mixture while stirring. The mixture was then heated to 100 ℃ and held until the acid number was below 103. The mixture was then cooled to 60 ℃ to which 1061.8 g of water was added828 and 3.7 grams of triphenylphosphine. The mixture was then heated to 110 ℃ while stirring and held at this temperature until the acid number was below 2. The mixture is then cooled to ambient temperature and stored. The number average molecular weight of the amide-polyether-polyester modified epoxy resin formed was 1664 and the Epoxy Equivalent Weight (EEW) was 408.6.

Partial D-synthesis of epoxy/dimer acid adducts

Will be provided with1022 dimer acid (26.95g, from Emory),828(32.96g, from Hexion) and triphenylphosphine (0.06g, from BASF) were added to a round bottom flaskEquipped with a mechanical stirrer, reflux condenser. A thermometer was connected to the addition funnel. Nitrogen was temporarily introduced into the flask. The flask was heated to 105 ℃ and the reaction was continued until an acid value reached the desired range of 85-88mg KOH/g. Will be in other quantities828(40.03g) was added to the flask via a funnel at 105 ℃ and nitrogen was temporarily introduced into the flask. The flask was heated to 116 ℃. A mildly exothermic reaction occurred and the reaction temperature rose to 177 ℃. The flask temperature was returned and maintained below 168 ℃ by cooling. The reaction continued until the acid value became less than 1, where the flask was cooled to room temperature. This synthesis produced a 43.6% epoxy/dimer acid adduct dispersed in an epoxy resin having an Epoxy Equivalent Weight (EEW) of 338.6.

Partial E-Synthesis of epoxy/CTBN adducts

Carboxylic acid terminated butadiene-acrylonitrile rubber (40g, available from Emerald Performance Material Corporation) and HYCAR1300X8828(60g) was charged to a round bottom flask equipped with a mechanical stirrer, thermometer and reflux condenser. The flask was warmed to 115 ℃ under nitrogen atmosphere. The mixture was then heated to 165 ℃ and stirred at this temperature until the acid value became less than 0.1, where the flask was cooled to room temperature. This synthesis produced a 43.9% epoxy/CTBN adduct dispersed in an epoxy resin having an Epoxy Equivalent Weight (EEW) of 357.

Part F-synthetic polyetheramine modified epoxy resins

187 g of828 was added to a pint metal can and heated in a 95 c oven for 30 minutes. The can was removed from the furnace and installedAn upper air motor driven mechanical agitator with shrouded blades for high shear mixing. 38.33 grams of Jeffamine D-400 was added to the tank with high speed mixing, and the mixture was stirred for 3 hours. During this time, the temperature of the mixture (initially at about 120 ℃ (measured by a thermocouple) was gradually reduced after 3 hours, the pot was cooled to room temperature.

Part G-evaluation 1K Binder

Test method

All the mechanical properties are in Germany&Tested on a 1mm thick Hot Dip Galvanized (HDG) substrate supplied by Lueg GmbH. The curing conditions used for all tests were 177 ℃ (350 ° f) for 30 minutes.

An extension of the ISO11343 method for wedge impacts, the "Adhesives-Determination of dynamic resistance to compact of high strength adhesive bonds — Wedgeimpact method" was used as described in Ford test method BU 121-01. Three binding samples were prepared for each test condition.

Wedge impact bonding preparation: cut 90mmX20mm samples. Teflon is added^TMThe tape was placed around the sample (both upper and lower samples) 30.0 + -0.2 mm from one end. Adhesive was then applied to the top 30 mm. Bond line thickness was maintained with 0.25mm (10 mil) glass beads. The adhesive squeezed from the edge of the sample was removed with a spatula. The sample was clamped together to keep the sample end and side flush. The bonded assembly was cured at 350 ° f (177 ℃) for 30 minutes. Any excess adhesive is then removed from the edge by sanding and a flat and parallel impact end is ensured, which allows the hammer to impact the entire sample simultaneously. The sample was labeled 40.0 + -0.2 mm from the binding end as a locator for consistent placement on the wedge. Placing the sample inOn the wedge, the marker on the sample is aligned with the tip of the wedge so that it is in the same position on the wedge each time. The sample is not pre-bent; instead, the unbound portion of the sample conforms to the shape of the wedge when the sample is placed on the wedge. An Instron Dynatup8200 type impact tester used with an integrated software package provided means for load application and data acquisition, respectively. The test frame is a device whose goal is to achieve a minimum impact energy of 150 joules (110.634lbf ft) and an impact velocity of at least 2 meters per second (6.562 ft./sec).

The combination was conditioned at room temperature for at least 24 hours. The conjugate was pulled apart in the tensile mode using an Instron model 5567.

Lap shear test: a 25mmX100mm sample was cut and scored at 12.5mm at one end. Adhesive was applied uniformly to the scored area of one of the samples for the bonded assembly of each. Uniformity of bond thickness was ensured by the addition of 0.25mm (10 mil) glass spacer beads. The spacer beads should be spread evenly over the material covering no more than 5% of the total bonding area. Other test specimens are placed on the bonded areas and spring-loaded Clips such as Binder Clips from Office Max or MiniSpring Clamp from Home Depot are attached to one of the bonds to each edge to hold the assembly together during baking. Excess adhesive extruded was removed with a spatula before baking. The bonded assembly is cured as specified, and after cooling, the remaining excess is sanded. The combination was allowed to settle at room temperature for at least 24 hours. The combination was pulled apart in the tensile mode using an Instron model 5567.

T-peeling: pairs of metal substrates were cut to a size of 25 mmx87.5mm. A 90 ° bend is made in one jaw from one end 12.5mm so that when joined together the pairs of sheets create a configuration: t-shaped. A thin layer of adhesive was applied to the three inch portion of the bonded side of one sheet. 0.25mm diameter glass spacer beads were applied evenly to the total bonding surface, which ensured coverage of 5% of the total bonding surface. The two sheets are placed together, which forms a T-shaped configuration, which is referred to as a T-pel assembly. 3 media binding clips were placed on the T-PEEL assembly to hold it together. Excess extruded binder is removed with a spatula before baking the assembly in a preconditioning oven at a given temperature as specified. The sample was allowed to cool and then the binding clamps were removed and sanded to polish any remaining extruded excess. The sample was pulled over INSTRON5567 at a rate of 127 mm/min. The T-Peel assembly in the Instron jar was conditioned for at least 30 minutes in an ambient room and tested in this room with a-30 ℃ test. The Instron5567 calculates the results by internal computer program in pounds per linear inch or newtons per millimeter.

Toughening agents having different epoxy end-caps on average and rubber particles having a core/shell structure 1K Binder composition

The following examples compare 1K binder compositions according to certain embodiments of the invention. The formulation is shown in table 5 and the mechanical properties of the 1K binder compositions are shown in tables 6-9, respectively.

TABLE 5

18. Synthesis example, example 2 from section D above.

19. Synthesis example, example 2 from section E above.

20. In that828 core/shell poly (butadiene) rubber dispersion (33%) obtained from Kaneka Texas Corporation.

21. Synthesis example, example 2 from section a above.

22. Synthesis example, example 2 from section F above.

23. Synthesis example, example 2 from section B above.

24. Synthesis example, example 2 from section C above.

25. A heat activated latent curing agent, available from ALZ Chem.

26. Catalytically active substituted ureas from ALZ Chem

27. Carbon Black, available from Phelps Dodge-Columbian Chemicals

28. Calcium oxide, obtained from Mississipi life, Co.

29. Hydrophobic fumed silica, available from Wacker Chemie AG

TABLE 6

Mechanical Properties of the Binders measured according to ISO527-1&2

TABLE 7

Overlap shear Strength (MPA)	Temperature of	Example 1	Example 2	Example 3	Example 4	Example 5
							Bonding area-25 x10x0.2mm	-40℃	31.4	28.4	29.1	28.4	29.6
GM-SAEJ1523	RT	25.3	24.5	23.5	24.9	25.8
							The traction speed is-10 mm/min.	+80℃	22.2	20.3	21.9	20.7	21.6

TABLE 8

TABLE 9

While specific embodiments of the invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.

Claims

1. A composition, comprising:

(a) a first component comprising:

(1) an epoxy adduct that is the reaction product of reactants comprising a first epoxy compound, a polyol, and an anhydride and/or diacid; and

(2) a second epoxy compound;

(b) rubber particles having a core/shell structure; and

(c) a second component that chemically reacts with the first component.

2. The composition of claim 1, further comprising (d) grapheme carbon particles.

3. A composition, comprising:

(a) a first component comprising:

(2) a second epoxy compound;

(b) graphene carbon particles; and

(c) a second component that chemically reacts with the first component.

4. A coated substrate comprising the composition of claim 3.

5. A composition, comprising:

(a) an epoxy-terminated toughener that is a reaction product of reactants comprising an epoxy compound, a polyol, and an anhydride and/or diacid; and

(b) a heat activated latent curing agent.

6. The composition of claim 5, further comprising (c) rubber particles having a core/shell structure.

7. The composition of claim 5, further comprising (c) grapheme carbon particles.

8. The composition of claim 5, further comprising:

(c) rubber particles having a core/shell structure; and

(d) graphene carbon particles.

9. The composition of claim 5, further comprising (c) an epoxy/CTBN adduct.

10. The composition of claim 5 further comprising (c) an epoxy/dimer acid adduct.

11. The composition of claim 5, further comprising:

(c) epoxy/CTBN adducts; and

(d) epoxy/dimer acid adducts.

12. A composition, comprising:

(a) an epoxy-terminated toughener that is a reaction product of reactants comprising an epoxy compound, an anhydride, and/or a diacid, and caprolactone; and

(b) a heat activated latent curing agent.

13. The composition of claim 12, further comprising (c) rubber particles having a core/shell structure.

14. The composition of claim 12, further comprising (c) grapheme carbon particles.

15. The composition of claim 12, further comprising:

(c) rubber particles having a core/shell structure; and

(d) graphene carbon particles.

16. The composition of claim 12, further comprising (c) an epoxy/CTBN adduct.

17. The composition of claim 12 further comprising (c) an epoxy/dimer acid adduct.

18. The composition of claim 12, further comprising:

(c) epoxy/CTBN adducts; and

(d) epoxy/dimer acid adducts.

19. The composition of claim 12, wherein the epoxy-terminated toughener comprises the reaction product of reactants comprising an epoxy compound, an anhydride and/or diacid, caprolactone; and diamines or higher functional amines.

20. A composition, comprising:

(a) an epoxy-terminated toughener that is a reaction product of reactants comprising an epoxy compound and a primary or secondary polyetheramine; and

(b) a heat activated latent curing agent.

21. The composition of claim 20, further comprising (c) rubber particles having a core/shell structure.

22. The composition of claim 20, further comprising (c) grapheme carbon particles.

23. The composition of claim 20, further comprising:

(c) rubber particles having a core/shell structure; and

(d) graphene carbon particles.

24. The composition of claim 20, further comprising (c) an epoxy/CTBN adduct.

25. The composition of claim 20 further comprising (c) an epoxy/dimer acid adduct.

26. The composition of claim 20, further comprising:

(c) epoxy/CTBN adducts; and

(d) epoxy/dimer acid adducts.