WO2016053641A1

WO2016053641A1 - Adduct composition

Info

Publication number: WO2016053641A1
Application number: PCT/US2015/050826
Authority: WO
Inventors: Yinzhong Guo; Ray E. Drumright; Erin B. Vogel; Justin M. Virgili; Mark F. Sonnenschein
Original assignee: Blue Cube Ip Llc
Priority date: 2014-09-29
Filing date: 2015-09-18
Publication date: 2016-04-07

Abstract

A curing agent adduct composition for curing epoxy resins, said adduct composition comprising an adduct reaction product of (a) at least one polyamine compound, (b) at least one alpha beta unsaturated acrylate compound such as a (meth)acrylate compound, and (c) at least one alpha beta unsaturated amide compound such as a (meth)acrylamide compound.

Description

ADDUCT COMPOSITION

FIELD

The present invention is related to amine adduct compositions and the use of such adduct compositions as curing agents for curing thermosettable resins such as epoxy resins.

BACKGROUND

Low levels of volatile organic compounds (VOCs) and high solid content are strong requirements for solvent based epoxy coatings, particularly for Maintenance and Protective (M&P) coatings. Besides lower viscosity epoxy resins, lower viscosity curing agents are also needed to enable preparation of high solid content, low VOC epoxy coating formulations. Use of low molecular weight polyamines (i.e. isophorone diamine, diethylene triamine, bisaminomethylcyclohexane, etc.) as curing agents deliver very low viscosity, however, these known amines suffer from compatibility problems with traditional liquid epoxy resins (LERs, such as DER331, a LER commercially available from The Dow Chemical Company); and the known amines create blooming and blushing problems which results in poor coating performance. Adducting amines with epoxy resins can resolve compatibility, blooming and blushing problems but adversely impacts viscosity. Therefore epoxy modified amine adducts usually contain high levels of residual free amine, solvent, or plasticizers to reduce their viscosity. Similarly, polyamide curing agents (yield coatings with good chemical resistance) are usually formulated with solvents or low molecular weight polyamines to reduce their viscosity either causing the problems mentioned above or bringing unwanted solvent into formulations.

Heretofore, various processes have been used to produce adducts using a Michael Addition reaction. For example, JP09291135 discloses a curing agent prepared by the Michael Addition reaction of: (a) an amine compound having at least two primary or secondary amino groups, (b) a (meth)acrylate compound containing at least two

(meth)acryloyl groups, and (c) a silane coupling agent having an amino or methacryloyl group and an active hydrogen and alkoxysilyl group. Also, JP09291135 discloses a curing resin composition consisting of a curing agent defined above and a liquid epoxy resin. The curing agent disclosed in JP09291135 is useful for a liquid epoxy resin composition. The resin composition is suitable for civil engineering and building material, e.g., concrete or mortar, for adhesives, repairing material, material for grouted cut-off, a floor-painting agent, a sealing agent and a coating agent. The curable resin composition has a low viscosity without using solvent. The curable resin composition forms a coated film having good adhesion and water resistance on a wet surface of concrete or mortar.

JP08198942 discloses an epoxy resin composition applied on a wet surface or in water, wherein the composition includes: (A) an epoxy resin, (B) a curing agent for the epoxy resin and (C) an inorganic filler. The curing agent, component (B), of the above composition is m-xylenediamine, bis-(aminomethyl) cyclohexane, methylene- di(cyclohexylamine) and/or norbornene-diamine. Component (B) is prepared by modifying an amine by the following methods: (l)a Mannich method of reacting amines with phenols and carbonyl group-containing compound; (2) an addition reaction method of reacting amines with an epoxy compound; (3) a Michael Addition modification method of reacting amines with a substituted acrylic compound; (4) a poly-amidation method of reacting an amide with polycarboxylic acid; and/or (5) a ketiminating modification method of reacting amines with a ketone compound.

The epoxy resin, component (A), of the above composition disclosed in JP08198942 is a multinuclear dihydric phenol polyglycidyl ether and/or polyglycidyl ether which is prepared by adding an alkyleneoxide to a multinuclear dihydric phenol and by glycidyl-etherification of the hydroxy group.

Components (A) and (B) of the above composition disclosed in JP08198942 are used in such amount that the equivalent ratio of the epoxy group in (A) to the active hydrogen in (B) is 1:0.5-2.0. The content of component (C) is 10 weight percent (wt ) to70 wt % in the composition. Component (C) is, for example, titanium dioxide, magnesium oxide or talc. The epoxy resin curable composition is suitable as a coating, an adhesive, a sealing material, and the like, for application on a wet surface or in water. The composition has good coating properties and adhesiveness on a wet surface or in water. The coated film resulting from the epoxy resin composition disclosed in JP08198942 has good corrosion resistance.

WO2013072052 discloses a process for preparing an amine adduct by reacting (A) a polyamine, (B) a polyester compound, and (C) a hydrocarbon compound. The amine adduct resulting from the reaction process of WO2013072052 is of particularly good suitability as a wetting agent and dispersant, especially for coatings and plastic applications.

EP0899287 discloses multi-branched compounds and a curable composition which is obtained by reacting a core compound obtainable from a Michael Addition reaction of (a) a polyamino compound having primary or secondary amino group(s), (bl) an active hydrogen-containing (meth)acrylic compound, and (c) a vinyl group-containing compound having a functional group reactable with the active hydrogen. Also, EP0899287 discloses (I) a curable composition containing the above multi-branched compound, water and/or another solvent; (II) a printing ink or coating composition containing the above multi- branched composition; and (III) a cured product obtainable by curing the above multi- branched compound or curable composition. The compound is used as a film forming material such as a coating composition, an ink, a resin for a sealant, a molding material, an adhesive or tackiness agent, a curing agent or reactive diluent. The compound provides a liquid compound having a relatively high molecular weight but a low viscosity and having excellent coating performances.

U.S. Patent Application Publication No. 20040048985 discloses adducts of polyfunctional acrylates and amine terminated polyolefins (H2C=CR-R4-(CH2-CH2- N(R2)-Rl-N(R3)-CH2-CH2-R4)m-CR=CH2). The adducts disclosed in US20040048985 are prepared via a Michael Addition reaction of an acrylate and the amine terminated polyolefin. The resultant adduct disclosed in US20040048985 can be further polymerized with acrylic monomers via free radical or radiation curing mechanisms or quaternized to improve dispersion in aqueous systems. The resultant adduct is also useful as binders in radiation curable compositions to provide clean chemistries at or near zero volatile organic compound (VOC) requirements for coatings, electronics, adhesive, and other low VOC application.

JP1996003282 discloses hardener compounds including: (A) a polyamine compound containing at least one of bis(aminomethyl) cyclohexane, epoxy modified bis(aminomethyl) cyclohexane and a Michael addition product of bis(aminomethyl) cyclohexane and (B) an amine compound having a 16C-18C alkyl. Also, JP1996003282 discloses an epoxy resin paint comprising an epoxy resin and the above hardener for the epoxy resin. None of the above references disclose an adduct composition containing both an amine functionality and an amide functionality or a process for preparing such an adduct. The above known epoxy resin compositions suffer from missing several key attributes required of the epoxy resin for its acceptable processability and downstream reliability including for example, low viscosity, low VOC, and high solids content.

It is therefore desired to provide an adduct composition containing both an amine functionality and an amide functionality which can be used as a curing agent in a curable coating formulation with enhanced rheological properties and when the formulation is cured, the cured coating exhibits increased performance properties including chemical resistance.

SUMMARY

One embodiment of the present invention is directed to an amine adduct composition. In general, the adduct composition may include the reaction product of: (a) at least one polyamine compound, (b) at least one alpha beta unsaturated acrylate compound, and (c) at least one alpha beta unsaturated amide compound. For example, the adduct reaction product can be made using (a) at least one polyamine compound, (b) at least one (meth)acrylate compound, and (c) at least one (meth)acrylamide compound. Generally, the adduct composition is made by modifying an amine with a combination of a (meth)acrylate compound and a (meth)acrylamide compound utilizing Michael Addition reactions.

The resultant adduct composition can be used as a curing agent in a thermosettable or curable composition wherein the adduct can be one component of the composition or formulation. The adduct composition contains both an amine functionality and an amide functionality. The adduct composition also exhibits several beneficial properties such as having a low viscosity and good compatibility with liquid epoxy resins (LERs). In addition, advantageously the adduct composition of the present invention does not display undesirable properties such as "blooming" and "blushing". The adduct composition, containing both an amine functionality and an amide functionality and when used as a curing agent in a curable coating formulation, also provides a resultant coating made from the curable formulation with beneficial coating performance properties such as coating chemical resistance.

Another embodiment of the present invention is directed to a process for preparing the above adduct. Still another embodiment of the present invention is directed to a curable composition or formulation including the above adduct of the present invention.

Yet another embodiment of the present invention is directed to a process for preparing the above composition or formulation.

And even still other embodiments of the present invention are directed to a cured thermoset product, such as a coating, manufactured from the above curable composition or formulation and a process therefor.

DETAILED DESCRIPTION

"Blooming" herein, with reference to a coating film surface, means a thin greasy or waxy layer on the cured coating film which causes grey cloudiness or gloss reduction of coatings.

"Blushing" herein, with reference to a coating surface, means white crystals or patches on the coating surface which causes grey cloudiness; gloss reduction or a milky haze visible in clear coatings.

Blooming and blushing are known to be caused by the reaction of low molecular weight amines, which are typically hygroscopic, with atmospheric carbon dioxide and moisture to form an ammonium carbamate or the salts of ammonium (bi-) carbonate.

A "Michael Addition reaction process" herein means nucleophilic addition of an amine or other nucleophile to an unsaturated carbonyl compound that results in saturated compounds or materials.

In its broadest scope, the present invention is directed to an amine adduct composition including a reaction product of: (a) at least one polyamine compound, (b) at least one alpha beta unsaturated acrylate compound, and (c) at least one alpha beta unsaturated amide compound. For example, the adduct composition can be made by modifying a polyamine with a combination of an acrylate compound and an acrylamide compound utilizing a Michael Addition reaction. One preferred embodiment of the present invention includes an adduct composition comprising the reaction product of: (a) at least one polyamine compound, (b) at least one (meth)acrylate compound, and (c) at least one (meth)acrylamide compound. In the preferred embodiment above, the concentrations of the above components for preparing the adduct composition generally can be, for example, from about 40 wt % to about 95 wt % of the at least one polyamine compound; from about 5 wt % to about 40 wt % of the at least one acrylate compound; and from about 0.1 wt % to about 20 wt % of the at least one acrylamide compound.

In general, the novel adduct composition of present invention can be prepared by adding the amine compound into a mixture of the acrylate compound and the acrylamide compound at a mixing temperature of from about 20 °C to about 70 °C with or without a strong base as catalyst such as l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or other tertiary amines. The novel adduct of the present invention can be used as a curing agent for curing thermosetting resins such as epoxy resins.

The amine compound useful for producing the curing agent adduct composition of the present invention can be for example, at least one polyamine compound. For example, the adduct formulation used to form the adduct reaction product can include an aliphatic polyamine, a cycloaliphatic polyamine, or a mixture thereof. In one preferred embodiment, the polyamine compound, component (a), when used to form the adduct reaction product, can include an aliphatic diamine, a cycloaliphatic diamine, or a mixture thereof.

Suitable polyamine compounds useful for producing the adduct composition of the present invention can be for example mono-, di-, tri-, and multi- cycloaliphatic diamines, triamines, and mono-, di-, tri-, and multi- non-cycloaliphatic diamines, such as norbornane diamine (NBDA), isophorone diamine (IPDA), cyclohexane dimethylene diamine, and the like; and mixtures thereof. In another embodiment, any one or more of the above described amine compounds can be used as a mixture or blend with polyaliphatic amines such as diethylenetriamine, triethylenetetraamine, and JEFF AMINE amines.

Generally, the amount of amine compound used in the preparation of the adduct composition of the present invention, may be for example, from about 40 wt % to about 95 wt % in one embodiment, from about 50 wt % to about 90 wt % in another embodiment; from about 60 wt % to about 85 wt % in still another embodiment; from about 60 wt % to about 85 wt % in yet another embodiment and from about 77 wt % to about 81 wt % in even still another embodiment, based on the total weight of the composition.

The alpha beta (α,β) unsaturated acrylate compound useful for producing the curing agent adduct composition of the present invention can be for example, at least one (meth)acrylate compound. For example, the adduct formulation used to form the adduct reaction product can include a multi-(meth)acrylate compound such as for example maleic alkylesters, alkyl (meth)acrylates, ethylene glycol di(meth)acrylate, di(ethylene glycol) di(meth)acrylate, propylene glycol di(meth)acrylates, dipropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylates, polyethylene glycol di(meth)acrylates,

2,2-dimethylpropalene glycol di(meth)acrylates, 2-ethyl propylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, neopentyl glycol propoxylate (1 PO/OH) diacrylate, tricyclo[5.2.1.0]decanedimethanol diacrylate, and mixtures thereof.

In one preferred embodiment, the multi-(meth)acrylate compound useful for the present invention may include for example one or more (meth)acrylic functional group terminated materials.

Generally, the amount of multi-(meth)acrylate compound used in the present invention, may be for example, from about 5 wt % to about 40 wt % in one embodiment, from about 10 wt % to about 35 wt % in another embodiment; from about 15 wt % to about 30 wt % in still another embodiment; and from about 15 wt % to about 20 wt % in yet another embodiment, based on the total weight of the composition.

The alpha beta (α,β) unsaturated amide compound useful for producing the curing agent adduct composition of the present invention can be for example, at least one (meth)acrylamide compound. For example, the adduct formulation used to form the adduct reaction product can include the (meth)acrylamide compound such as (meth)acrylamide, maleic amides, amide terminated polyesters, amide terminated polyethers, and mixtures thereof.

In one preferred embodiment, the (meth)acrylamide compound useful for the present invention may include for example acrylamide, methacrylamide, maleic diamide, and mixtures thereof.

Generally, the amount of (meth)acrylamide compound used in the present invention, may be for example, from about 0.1 wt % to about 20 wt % in one embodiment, from about 1 wt % to about 15 wt % in another embodiment; from about 3 wt % to about 12 wt % in still another embodiment; and from about 5 wt % to about 9 wt % in yet another embodiment, based on the total weight of the composition. The concentration of the (meth)acrylamide compound used to make the adduct reaction product is important because if too much amide compound is used beyond 20 wt %, then insufficient amine functionality will be present in the adduct product to be useful as an effective hardener. Also, with too much amide compound, the viscosity of the adduct product will be high enough to necessitate the use of a solvent to reduce the viscosity of the adduct product. If the concentration of the amide compound is too low, below 0.1 wt %, the cured coating made using the adduct curing agent of the present invention will exhibit a poor chemical resistance property. It is possible that other rheological issues can arise when the amide compound is used outside of the above concentrations.

As one illustration of the present invention, an adduct composition product which comprises the reaction product of: (a) at least one polyamine compound, (b) at least one (meth) aery late compound, and (c) at least one (meth)acrylamide compound; results in an adduct product that contains both an amine functionality and an amide functionality. In general, the molar ratio of the amine functionality (of component (a)) to the amide functionality (of component (c) may be from about 25:1 to about 5: 1 in one embodiment, from about 22:1 to about 6:1 in another embodiment, and from about 20:1 to about 8:1 in still another embodiment.

In another embodiment, the adduct composition product may have a molar ratio of the amine functionality (of component (a)) to the acrylic functionality (of component (b) in the range of from about 25:1 to about 5:1 in one embodiment, from about 20: 1 to about 6:1 in another embodiment, and from about 10:1 to about 8:1 in still another embodiment.

The adduct composition of the present invention can include, as an optional component (d), a catalyst wherein the concentration of the at least one catalyst compound, component (d), when used to form the adduct reaction product, is from 0 weight percent to about 0.5 weight percent.

The catalyst compound can include for example, when used to form the adduct reaction product, one or more compounds selected from the group consisting of l,8-diazabicyclo[5.4.0]undec-7-ene, triethylamine (TEA), other tertiary amine catalysts, or mixtures thereof.

As an illustration of some of the preferred adduct composition products of the present invention useful as curing agents, the curing agents can be shown by the following Structures (I) - (IV). The Structures (I) - (IV) are general chemical structures of examples of the curing agents of the present invention; and the curing agents can include, but are not limited to, compositions of one or more of the following structures.

Structure (I)

Structure (IV)

In the above Structures (I) to (IV), Y can be a numerical value of from 1 to 3; R can be a hydrocarbon radical containing up to about 30 carbon atoms, ((CH2)_mZ)_n(CH2)_m where Z is O or NH, and m is a numerical value of from 2 to 16, and n is a numerical value of from 1 to 100; R' can be CH₂CH₂, CH₂CH₂CH₂, CH₂CHCH₂ , CH₂CH₂CH₂CH₂, CH₂CH₂OCH₂CH₂, CH₂CH₂CH₂OCH₂CH₂CH₂, CH₃C(CH₂)₃, CH₃CH₂C(CH₂)₃, C(CH₂)₄, (CH₃) ₂C(CH₂) ₂, ((CH₂)_mO)_n(CH₂)_m where m is a numerical value of from 2 to 16, and n is a numerical value of from 1 to 100; and any other alkylene segments.

The hydrocarbon radicals represented by R in the above chemical structures, are known to those skilled in art and are organic groups which consist solely of hydrogen and carbon. According to the present invention, the term "hydrocarbon radical", in reference to the R group in the above chemical structures, refers to a hydrocarbyl radical R that preferably can contain CI to about C30 carbon atoms, preferably CI to about C25 carbon atoms, more preferably C2 to C20 carbon atoms, and most preferably from C2 to C16 carbon atoms per molecule; and such hydrocarbon radicals include both aliphatic

(which can include those radicals that are based on the presence of double or triple bonds in the chemical structure) and aromatic or arene radicals (which include those radicals that can contain a benzene ring). The hydrocarbyl radical can be, for example, an alkyl radical, an alkenyl radical, cycloalkyl radical, an aryl radical, an alkyl aryl (alkaryl) radical, an aryl alkyl (aralkyl) radical, or combinations of two or more thereof. The hydrocarbon radical R may be optionally substituted or unsubstituted. The hydrocarbon group R may also include a saturated or unsaturated hydrocarbon group; any substituents present in the composition should be inert in the composition and reactions of the present invention process. The hydrocarbon group R may also be a linear (straight-chained), branched, cyclic, aliphatic, or aromatic group.

In one embodiment, for example, hydrocarbon radicals, R, cars be an alky] having as few as 2 carbon atoms; but hydrocarbon groups with 3, 4 or more carbon atoms may be used in other embodiments. A representative sample of alkyl hydrocarbon radicals may include, for example but not limited to, straight chain and branched chain alkyl hydrocarbons radicals based on methyl, ethyl, propyl, butyl, amy], hexyl, he tyl, octyl, lauryl, pentadecyl, octadecyl, dodecyl, decenyl, lauryl, stearyl, and the like; and alkenyl hydrocarbon radicals may include, for example but not limited to, alkenyl hydrocarbons radicals based on phenyl, naphthyl, benzyl, ethylphenyl, cyclohexyl, ethylcyclohexyl, and the like.

As aforementioned, the adduct composition of the present invention useful as curing agent can include a combination or mixture of one or more compounds of

Structures (I) - (IV) in some embodiments. In addition to one or more compounds of Structures (I) - (IV) present in the adduct composition, in still another embodiment, it is within the scope of the present invention to include other compounds with no amide functionality in the adduct composition. For example, a compound having the general chemical structure of Structure (V) is an example of a compound with no amide

functionality that may be optionally present in the adduct composition of the present invention.

Structure (V)

In the above Structures (V), Y, R and R' can be the same as Y, R and R' as discussed above with reference to Structures (I) to (IV).

Other optional compounds, such as compounds used as unreacted raw materials used to prepare the adduct composition or compounds derived from the raw materials used to prepare the adduct composition, may be present in the adduct composition.

The process used for preparing the adducts of the present invention includes a Michael Addition reaction process which includes the steps of air purging with a nitrogen gas for 1-5 minutes, charging the amines and acrylamides into a reactor, and mixing the materials in the reactor until the acrylamides are totally dissolved. Then, the acrylates are charged into the reactor. Depending on the reactivity of the raw materials, a catalyst such as DBU may optionally be added to the reaction mixture in a concentration of from about 0.1 wt % to about 0.5 wt % based on total materials. After an exotherm of reaction occurs, the reaction mixture is heated to a temperature of from about 50 °C to about 80 °C for a time period of from about 0.5 hour to about 1 hour to finish the reaction. 1H NMR can be used to monitor the reaction by tracking the disappearance of C=C double bonds. After the reaction is complete, the resulting product can be transferred to a container for further processing or storage.

In general, the reaction process for producing the adduct composition of the present invention includes carrying out the reaction at process conditions to enable the preparation of an effective adduct composition having the desired balance of properties for a particular application. For example, generally, the reaction temperature for preparing the adduct composition can be in the range of from about 20 °C to about 80 °C in one embodiment, from about 25 °C to about 75 °C in another embodiment, and from about 30 °C to about 70 °C in still another embodiment.

The reaction time of the reaction may be generally from about 1 hour to about 4 hours in one embodiment, from about 1 hour to about 3 hours in another embodiment, and from 1 hour to about 2 hours in still another embodiment.

The preparation of the adduct composition of the present invention, and/or any of the steps thereof, may be a batch or a continuous process. The equipment employed to carry out the reaction includes equipment known to those skilled in the art.

The adduct composition product prepared by the process of the present invention is a novel composition with unexpected and unique properties. For example, it has been found that the adduct composition product of the present invention exhibits a low viscosity. Surprisingly, in one embodiment, the adduct composition product of the present invention exhibits a viscosity of less than or equal to (<) about 100,000 mPa-s at 25 °C. Generally, the viscosity of the adduct composition product of the present invention can be

< about 100,000 mPa-s in one embodiment, < about 50,000 mPa-s in another embodiment,

< about 20,000 mPa-s in still another embodiment at 25 °C.

Because the modified adduct product has a low viscosity described above, the product can be used without using solvents or diluents for the sole purpose of reducing the viscosity of the product if desired. The adduct product of the present invention is easily processed and readily handled in enduse processes for forming other products.

Besides lowering the viscosity and improving the processability of the adduct product of the present invention, the adduct composition also surprisingly exhibits a much better compatibility with epoxy resins than the compatibility of other known adducts. For example, the compatibility of the adduct composition with epoxy resin can be observed by the appearance of formulated liquid coatings. Clear formulations with no haze or phase separation indicated good formulation compatibility. In cured coating films, the lack of blooming and blushing is indicative of good compatibility and reactivity and can be assessed with known gloss measurements. The adduct of the present invention can be used as a curing agent for epoxy resin compositions or formulations. In turn, the epoxy resin formulations which are cured with the adduct of the present invention may be used in thermoset systems where conventional epoxy resins are used. For instance, some non-limiting examples of applications wherein the epoxy resin formulation containing the curing agent adduct of present invention may be used include, for example, coatings, adhesives, inks, composites, and any applications that traditionally use a curing agent.

In another embodiment, the adduct of the present invention may also be used as a dual diluent/curing agent for curable formulations to replace high viscosity curing agents. Other examples of applications for the adduct composition and the epoxy resin formulation with the adduct curing agent can be envisioned by those skilled in the art.

As aforementioned, one embodiment of the present invention is directed to a curable epoxy resin composition or formulation containing the above described adduct as a curing agent for the epoxy resin composition or formulation. The adduct curing agent of the present invention can be used in epoxy resin formulations which are typically cured using a conventional curing agent to produce a cured product or thermoset from conventional thermosetting resins such as epoxy resins. For example, the curable epoxy resin composition containing the adduct as a curing agent may include: (i) an epoxy resin; (ii) the adduct composition of the present invention as a curing agent; and (iii) optionally, any other desired additive such as a curing reaction catalyst; other curing agents different from the adduct composition of the present invention; other (meth)acrylate resins; diluents; and/or pigments or fillers such as Ti0₂, iron oxide, BaS0₄, silica, mica, CaC0₃, clay, and the like; or mixtures thereof.

The curable formulation of the present invention includes at least one epoxy resin as component (i). The epoxy resins used herein may be monomeric, oligomeric, or polymeric compounds containing at least one vicinal epoxy group. The epoxy resin may be aliphatic, cycloaliphatic, aromatic, cyclic, heterocyclic or mixtures thereof. The epoxy resin may be saturated or unsaturated. The epoxy resins may be substituted or unsubstituted. An extensive enumeration of epoxy resins useful in the present invention is found in Lee, H. and Neville, K., "Handbook of Epoxy Resins," McGraw-Hill Book Company, New York, 1967, Chapter 2, pages 257-307; incorporated herein by reference. The epoxy resins, used in embodiments disclosed herein of the present invention, may vary and include conventional and commercially available epoxy resins. The epoxy resin component of the resin composition used herein may include a single epoxy resin compound used alone or a mixture of two or more epoxy compounds used in combination. The epoxy resin, also referred to as a polyepoxide, may be a product that has, on average, more than one unreacted epoxide unit per molecule. In choosing epoxy resins for compositions disclosed herein, consideration should be given to properties of the final product, and to viscosity and other properties that may influence the processing of the resin composition.

Suitable conventional epoxy resin compounds utilized in the composition of the present invention may be prepared by processes known in the art, such as for example, a reaction product based on the reaction of an epihalohydrin and (1) a phenol or a phenol type compound, (2) an amine, or (3) a carboxylic acid. Suitable conventional epoxy resins used herein may also be prepared from the oxidation of unsaturated compounds. For example, epoxy resins used herein may include reaction products of epichlorohydrin with

polyfunctional alcohols, phenols, bisphenols, halogenated bisphenols, hydrogenated bisphenols, novolac resins, o-cresol novolacs, phenol novolacs, polyglycols, polyalkylene glycols, cycloaliphatics, carboxylic acids, aromatic amines, aminophenols, or combinations thereof. The preparation of epoxy compounds is described for example in Kirk- Othmer, Encyclopedia of Chemical Technology, 3rd Ed., Vol. 9, pp 267-289.

In one embodiment, suitable phenol, phenol-type or polyhydric phenol compounds useful for reacting with an epihalohydrin to prepare an epoxy resin include, for example, the polyhydric phenol compounds having an average of more than one aromatic hydroxyl group per molecule such as, for example, dihydroxy phenols; biphenols;

bisphenols such as bisphenol A, bisphenol AP (l,l-bis(4-hydroxyphenyl)-l-phenyl ethane), bisphenol F, or bisphenol K; halogenated biphenols such as tetramethyl-tetrabromobiphenol or tetramethyltribromobiphenol; halogenated bisphenols such as tetrabromobisphenol A or tetrachlorobisphenol A; alkylated biphenols such as tetramethylbiphenol; alkylated bisphenols; trisphenols; phenol- aldehyde novolac resins (i.e. the reaction product of phenols and simple aldehydes, preferably formaldehyde) such as phenol-formaldehyde novolac resins, alkyl substituted phenol-formaldehyde resins, phenol- hydroxybenzaldehyde resins, alkylated phenol-hydroxybenzaldehyde resins, or cresol-hydroxybenzaldehyde resins; halogenated phenol- aldehyde novolac resins; substituted phenol-aldehyde novolac resins; phenol-hydrocarbon resins; substituted phenol-hydrocarbon resins; hydrocarbon-phenol resins; hydrocarbon-halogenated phenol resins; hydrocarbon-alkylated phenol resins;

resorcinol; catechol; hydroquinone; dicyclopentadiene-phenol resins; dicyclopentadiene- substituted phenol resins; or combinations thereof.

In another embodiment, suitable amines useful for reacting with an epihalohydrin to prepare an epoxy resin include, for example, diaminodiphenylmethane, aminophenol, xylene diamine, anilines, or combinations thereof.

In still another embodiment, suitable carboxylic acids useful for reacting with an epihalohydrin to prepare an epoxy resin include, for example, phthalic acid, isophthalic acid, terephthalic acid, tetrahydro- and/or hexahydrophthalic acid,

endomethylenetetrahydrophthalic acid, isophthalic acid, methylhexahydrophthalic acid, or combinations thereof.

A few non-limiting embodiments of the epoxy resin useful in the present invention include, for example, aliphatic epoxides prepared from the reaction of epihalohydrins and polyglycols such as trimethylpropane epoxide; diglycidyl- 1,2- cyclohexane dicarboxylate, or mixtures thereof; diglycidyl ether of bisphenol A; diglycidyl ether of bisphenol F; resorcinol diglycidyl ether; triglycidyl ethers of para-aminophenols; halogen (for example, chlorine or bromine) -containing epoxy resins such as diglycidyl ether of tetrabromobisphenol A; epoxidized phenol novolac; epoxidized bisphenol A novolac; an oxazolidone-modified epoxy resin; an epoxy-terminated polyoxazolidone; and mixtures thereof.

Suitable commercially available epoxy resin compounds utilized in the composition of the present invention may be for example, epoxy resins commercially available from The Dow Chemical Company such as the D.E.R.™ 300 series, the D.E.N.™ 400 series, the D.E.R.™ 500 series, the D.E.R.™ 600 series and the D.E.R.™ 700 series of epoxy resins. Examples of bisphenol A based epoxy resins useful in the present invention include commercially available resins such as D.E.R.™ 300 series and D.E.R.™ 600 series, commercially available from The Dow Chemical Company. Examples of epoxy novolac resins useful in the present invention include commercially available resins such as D.E.N.™ 400 series, commercially available from The Dow Chemical Company.

Epoxy resin compounds useful in the present invention can include for example advanced epoxy resin polymers and partly advanced epoxy resin compositions such as the advanced epoxy resin polymers described in U.S. Patent No. 4,596,861, EP0187855 Bl, and WO1989008121A1. Generally, advanced epoxy resins are prepared from a liquid diglycidyl ether of bisphenol A and bisphenol A such that the advanced epoxy resins have an equivalent weight in the range of 3,000 to 3,900 and a weight average molecular weight of 13,000 to 17,000.

As another illustrative embodiment of the present invention, the epoxy resin may be a liquid epoxy resin, such as D.E.R. 383 a diglycidylether of bisphenol A

(DGEBPA) having an epoxide equivalent weight of from about 175 to about 185, a viscosity of about 9.5 Pa-s and a density of about 1.16 g/cc. Other commercial epoxy resins that can be used for the epoxy resin component can be D.E.R. 330, D.E.R. 331, D.E.R. 354, or D.E.R. 332; and blends or mixtures thereof.

Other suitable epoxy resins useful as component (I) are disclosed in, for example, U.S. Patent Nos. 3,018,262;7,163,973; 6,887,574; 6,632,893; 6,242,083;

7,037,958; 6,572,971; 6,153,719; and 5,405,688; PCT Publication WO 2006/052727; U.S. Patent Application Publication Nos. 20060293172 and 20050171237, each of which is hereby incorporated herein by reference. Examples of epoxy resins and their precursors suitable for use in the compositions of the present invention are also described, for example, in U.S. Patent Nos. 5,137,990 and 6,451,898, which are incorporated herein by reference.

In general, the concentration of the epoxy resin compound used in the present invention may range generally from about 1 wt % to about 99 wt % in one embodiment, from about 20 wt % to about 70 wt % in another embodiment, from about 30 wt % to about 50 wt % in still another embodiment, and from about 35 wt % to about 40 wt % in yet another embodiment, based on the total weight of the components in the resin composition.

In general, the adduct of the present invention described above is used as the curing agent (also referred to as a hardener or crosslinking agent), component (ii), and is blended with the epoxy resin, component (i), to prepare the curable composition or formulation. The curable formulation can then be cured to form a cured product or thermoset.

Generally, the amount of adduct curing agent used in the curable formulation of the present invention will depend on the enduse of the curable composition. For example, as one illustrative embodiment, when the curable formulation is used to prepare a coating, the concentration of the adduct curing agent can be generally from about 5 wt % to about 60 wt % in one embodiment, from about 10 wt % to about 30 wt % in another embodiment; and from about 15 wt % to about 20 wt % in still another embodiment; based on the weight of the components in the curable formulation.

In another illustrative embodiment, when the curable formulation is used to prepare a coating, the epoxy resins are formulated with the adduct curing agent at an epoxide to amine hydrogen (NH) equivalent ratio of from about 0.3:1 to about 1.3:1 in one embodiment, from about 0.6:1 to about 1.2:1 in another embodiment, and from about 0.7: 1 to about 1.0: 1 in still another embodiment.

In preparing the curable resin formulation of the present invention, optional compounds or additives may be used in the formulation including for example at least one curing catalyst to facilitate the reaction of the epoxy resin composition with the adduct curing agent. The curing catalyst useful in the present invention may include for example, any homogeneous or heterogeneous catalyst known in the art which is appropriate for facilitating the reaction between an epoxy resin and a curing agent may be used. The catalyst may include for example, but are not limited to, imidazoles, tertiary amines, phosphonium complexes, Lewis acids, or Lewis bases, transition metal catalysts, and mixtures thereof.

The catalyst useful in the present invention may include for example a Lewis acid such as boron triflouride complexes, Lewis bases such as tertiary amines like diazabicycloundecene and 2-phenylimidazole, quaternary salts such as

tetrabutyphosphonium bromide and tetraethylammonium bromide, and organoantimony halides such as triphenylantimony tetraiodide and triphenylantimony dibromide; and mixtures thereof.

Generally, the amount of cure catalyst, when used in the curable composition, may be for example from 0 wt % to about 5 wt % in one embodiment, from about 0.01 wt % to about 3 wt % in another embodiment; from about 0.1 wt % to about 2 wt % in still another embodiment; and from about 0.2 wt % to about 1 wt % in yet another embodiment. The catalyst level can be adjusted to allow adequate processing in the final application.

Other optional compounds that may be added to the curable composition of the present invention may include compounds that are normally used in resin formulations known to those skilled in the art for preparing curable compositions and thermosets. For example, the optional components may comprise compounds that can be added to the composition to enhance application properties (e.g. surface tension modifiers or flow aids), reliability properties (e.g. adhesion promoters) the reaction rate, the selectivity of the reaction, and/or the catalyst lifetime.

Other optional compounds or additives that may be added to the curable composition of the present invention may include, for example, de-molding agents;

accelerators, a solvent to lower the viscosity of the formulation further, other resins such as a phenolic resin that can be blended with the other ingredients in the curable formulation, other curing agents different from the adduct curing agent, fillers, pigments, toughening agents, flow modifiers, adhesion promoters, diluents, stabilizers, plasticizers, catalyst deactivators, flame retardants, and mixtures thereof.

Generally, the amount of other optional components or additives, when used in the present invention, may be for example from 0 wt % to about 40 wt % based on the total weight of the compounds in the composition. When an optional additive (e.g., a toughening agent) is used and only a relatively small amount is required for its use, the desirable amount of the additive can be on the lower end of the above range such as for example, from about to about 10 wt % in one embodiment, from about 0.01 wt % to about 5 wt % in another embodiment; from about 0.1 wt % to about 3 wt % in still another embodiment; and from about 0.2 wt % to about 1 wt % in yet another embodiment.

On the other hand, when an optional additive is used and a relatively larger amount is required for its use, the desirable amount of the additive can be on the higher end of the above range. For example, when an optional compound such as a pigment is used, the pigment may be added to the curable composition of the present invention generally, from 0 wt % to about 40 wt % in one embodiment, from about 5 wt % to about 30 wt % in another embodiment; and from about 10 wt % to about 20 wt % in still another

embodiment, based on the weight of the components in the curable composition.

In a preferred embodiment, a pigment may be added to the curable composition of the present invention to enhance application properties and reduce cost. The pigments useful in the present invention may include for example compounds that are normally used in coating formulations known to those skilled in the art for preparing curable compositions and thermosets. For example, the optional pigment that may be added to the composition, may include Ti0₂, iron oxide, BaS0₄, silica, mica, CaC0₃, clay, and the like; and mixtures thereof.

In general, another embodiment of the present invention is directed to a process for preparing a curable epoxy resin composition comprising admixing the adduct composition described above and at least one epoxy thermosetting resin.

The process for preparing the curable formulation of the present invention includes admixing (i) at least one epoxy resin compound; (ii) the adduct composition described above which is used as a curing agent for the epoxy resin compound; and

(iii) optionally, any other optional ingredients as desired and described above. For example, the preparation of the curable resin formulation of the present invention is achieved by blending, in known mixing equipment, the epoxy resin, the adduct curing agent, and optionally any other desirable additives. Any of the above-mentioned optional additives, for example a curing catalyst, may be added to the composition during the mixing or prior to the mixing to form the formulation.

All the compounds of the curable formulation are typically mixed and dispersed at a temperature enabling the preparation of an effective curable epoxy resin formulation having the desired balance of properties for a particular application. For example, the temperature during the mixing of all components may be generally from about -10 °C to about 40 °C in one embodiment, and from about 0 °C to about 30 °C in another embodiment. Lower mixing temperatures help to minimize reaction of the epoxide and curing agent in the composition to maximize the pot life of the composition.

The preparation of the curable formulation of the present invention, and/or any of the steps thereof, may be a batch or a continuous process. The mixing equipment used in the process may be any vessel and ancillary equipment well known to those skilled in the art.

Some of the beneficial properties exhibited by the curable formulation may include for example, low viscosity, high solids content, and low VOC (volatile organic compounds). For example, the curable epoxy formulation prepared by the above process using the adduct curing agent of the present invention advantageously exhibits a low viscosity for example a viscosity of less than or equal to (<) about 10,000 mPa-s at 25 °C. Generally, the viscosity of curable formulation can be from about 10,000 mPa-s to about 500 mPa-s in one embodiment, from about 8,000 mPa-s to about 1,000 mPa-s in another embodiment, and from about 6,000 mPa-s to about 2,000 mPa-s in still another embodiment at 25 °C.

Because the curable formulation has a low viscosity as described above, the curable formulation can be used without using solvents or diluents for the sole purpose of reducing the viscosity of the curable formulation's processability. In other words, the curable formulation can be easily processed and readily handled in enduse processes for forming thermoset products.

Also, the curable formulation prepared by the above process using the adduct of the present invention advantageously exhibits a high solids content for example a solids content of greater than or equal to (>) about 70 wt %. Generally, the solids content of the curable formulation can be from about 50 % to about 100 % in one embodiment, from about 60 wt % to about 95 wt % in another embodiment, and from about 70 wt % to about 90 wt % in still another embodiment.

Another beneficial property of the curable formulation of the present invention includes a curable formulation that advantageously exhibits low VOC content for example a VOC content of < about 500 g/L. Generally, the VOC content of the curable formulation can be < about 500 g/L in one embodiment, < about 300 g/L in another embodiment, and < about 200 g/L in still another embodiment. The VOC content of the curable formulation is ideally zero and in general can be from about 10 g/L to < about 500 g/L.

The above curable formulation, when cured, endows the cured thermosets or cured articles such as coatings made from the curable formulation with excellent flexibility, impact resistance, and chemical resistance which can be attributable to the adduct curing agent of the present invention being used in the formulation. The properties of the cured thermoset product are discussed in more detail herein below.

Another embodiment of the present invention includes curing the curable resin formulation discussed above to form a thermoset or cured article. For example, the curing of the thermosettable composition or curable resin formulation may be carried out at a predetermined temperature and for a predetermined period of time sufficient to cure the resin composition. For example, the temperature of curing the formulation may be generally from about 10 °C to about 200 °C; preferably from about 25 °C to about 100 °C; and more preferably from about 30 °C to about 90 °C; and the curing time may be chosen between about 1 minute to about 4 hours, preferably between about 5 minutes to about 2 hours, and more preferably between about 10 minutes to about 1 hour. Below a period of time of about 1 minute, the time may be too short to ensure sufficient reaction under conventional processing conditions; and above about 4 hours, the time may be too long to be practical or economical.

The curable formulation of the present invention having as one component the adduct curing agent of the present invention as described above may be used to manufacture a cured thermoset product for various applications. The cured product (i.e. the cross-linked product made from the curable formulation) of the present invention shows several improved and beneficial performance properties over conventional cured thermosets made from curable compositions containing conventional curing agents. When the adduct is used as a curing agent in a curable coating formulation, for example, the curable formulation provides a resultant cured coating with beneficial coating performance properties.

For example, the cured coating product advantageously does not display the undesirable property of "blooming". The blooming phenomena resulting in a cured coating product may be an indication of the curing agent not being compatible with the epoxy resin. In the present invention, no blooming is visually detected in a clear coat sample which may be the result of an improved compatibility property of the adduct with the epoxy resin.

In addition, the cured coating product advantageously does not display the undesirable property of "blushing". The blushing phenomena, similar to the blooming phenomena, may result in a cured coating product because of the incompatibility of the curing agent with the epoxy resin. In the present invention, no blushing is visually detected in a clear coat sample which may be the result of an improved compatibility property of the adduct with the epoxy resin.

As aforementioned, some non-limiting examples of end use applications wherein the epoxy resin formulation containing the curing agent adduct of present invention may be used include, for example, coatings, adhesives, inks, and any applications that traditionally use a curing agent or a co-curing agent. The beneficial properties of the cured product can also be measured and evaluated to determine the desired end use of the curable formulation and the cured product. For example, the epoxy resin formulation of the present invention can be used for preparing a coating wherein the cured coating product exhibits a combination, i.e. a balance, of advantageous properties required for such coating enduse including for example processability, Tg, mechanical performance, chemical resistance performance, and other properties such as the properties described above.

EXAMPLES

The following examples and comparative examples further illustrate the present invention in detail but are not to be construed to limit the scope thereof.

In the following Examples, various terms and designations are used including for example the following:

"AHEW" stands for amine hydrogen equivalent weight which is theoretically calculated from non-reacted or residual amine hydrogen and given units of gram per amine hydrogen.

"NBDA" stands for norbornane diamine and is a product commercially available from Mitsui Fine Chemicals Inc.

"IPDA" stands for isophorone diamine and is a product commercially available from Aldrich.

M-cure 201 is an acrylate reactive diluent with an acrylate equivalent weight of 95-100 (g/mole acryl group) and is a product commercially available from Sartomer USA, LLC.

Acrylamide is a product commercially available from Aldrich.

DER331 is an epoxy resin having an EEW of 189 and commercially available from The Dow Chemical Company.

"DBU" stands for l,8-diazabicyclo[5.4.0]undec-7-ene and a product commercially from Aldrich.

In the following Examples, standard analytical equipment and methods are used such as for example: Viscosity

Viscosity was calculated in accordance with Brookfield viscosity method using a Brookfield HADVIII+ Viscometer at 25 °C in accordance with ASTM D-445. For example, a 9 gram (g) sample was loaded into an adapter, put a # 31 spindle, spun in a range 25-35% torque depending upon the sample to obtain a stabilized spin rate of between 31 and 34 rotations per min. Viscosity data was collected following 2 min of stabilization. The viscosity measurements are reported in units of mPa-s.

AHEW

AHEW is calculated based on the following theoretical calculation:

AHEW = total amount product (g)/(total molar amine hydrogen - reacted molar amine hydrogen)

Hardness

Pendulum Hardness was measured using a Tester from BYK Gardner equipped with a Konig pendulum. The test was run according to ISO 1522 standard and set to measure hardness in seconds. This method evaluates hardness by measuring the damping time in seconds of an oscillating pendulum as its amplitude decreases from 6° to 3°. The hardness pendulum rests on the test surface and pivots on two 5mm in diameter stainless steel balls. When the pendulum is set into motion, the balls roll on the surface and put pressure on the coating. Depending on the elasticity of the coating, the damping will be stronger or weaker. If there are no elastic forces, the pendulum will damp stronger. High elasticity will cause weak damping. In other words, the amplitude of the pendulum oscillations decreases more rapidly with softer coatings resulting in shorter damping times.

Dry Time

The method described in ASTM DC 1640-03 (2001) was used to determine the dry time of the coatings prepared in the examples.

Gloss

The gloss of the coatings was measured with the BYK micro-TRI-gloss gloss meter. Five measurements were taken from five random locations over the entire panel. The average of those five measurements were calculated and reported. The gloss meter computes 20, 60 and 85 degrees gloss and depending on application one, two or all three of those measurements were used.

Coating Thickness

Positector 6000 was used to measure coating thickness. Five measurements were taken from five random locations and an average was calculated and reported. The Positector measures on both steel and aluminum, the vast majority of the testing done was on the phosphate coated steel panels.

Solvent Resistance

Solvent resistance testing was performed using the (methyl ethyl ketone) MEK double rub test in accordance with ASTM D5402. For instance, MEK Double Rub Test was performed using the semi-automatic MEK Double Rub Tester made by DJH DESIGNS INC. The testing continued until the coating was rubbed through to the substrate with the MEK or a maximum of 200 double rubs were completed without breakthrough.

Flexibility

Mandrel bend tests of coatings were carried out according to the procedure described in ASTM D522 (test method B). A BYK Gardner Conical Mandrel Bending Tester was used to measure the elongation and adhesion of a coated film after a bending stress. The use of the BYK Tester enabled testing of various bending radii (3.2 mm to 38.1 mm) simultaneously. According to this Test, a test panel was bent 180 degrees around the conical mandrel with the coated side up. The panel was then inspected for cracking and/or delamination of the coating from the substrate. Results were measured in terms of the length of cracking or delamination in millimeters from the narrowest (3.2 mm) end of the bend.

Chemical Resistance

The following chemicals were used to evaluate the chemical resistance of the substrate coating samples: 10 % sulfuric acid (H₂SO₄), 3 % acetic acid, 10 % sodium hydroxide (NaOH), 3 % sodium chloride (NaCl), xylene, and ethanol (EtOH).

A couple drops of the above specified chemicals (including 3 wt % acetic acid in water, 10 % H₂SO₄ in water, 10 wt % NaOH solution, 3 wt % NaCl in water, xylene, or EtOH) were deposited onto a coated panel. For the specified chemicals with low surface tension or quick evaporation, filter papers (25 mm diameter) were placed on the coatings prior to contacting the coated panel with the specified chemical. Plastic caps were used to cover the resulting droplets of chemicals on the surface of the coated panel or the saturated filter papers. After 24 hours, the chemicals were washed away with water and the panels were dried with paper towels. The coatings were immediately visually inspected for any signs of chemical attack or staining; and such inspection was ranked on a 1-5 rating scale as follows: 5 = No visible affect, 4 = Slight blush, 3 = Major blush, Slight blister, change in touch, 2 = Major blisters, and 1 = Coating failure.

Impact Resistance

Impact resistance for direct impact and indirect impact was calculated using that pendulum hardness measured using a Pendulum Hardness Tester from BYK Gardner equipped with a Konig pendulum in accordance with ISO 1522. Hardness was measured in seconds. For instance, by measuring the damping time in seconds of an oscillating pendulum as its amplitude decreases from 6 degrees (°) to 3°. The pendulum rests with 2 stainless steel balls, 5 mm in diameter, on the coating surface. When the pendulum is set into motion, the balls roll on the surface and put pressure on the coating. Depending on the elasticity of the coating, the damping will be stronger or weaker. If there are no elastic forces, the pendulum will damp stronger. High elasticity will cause weak damping. In other words, the amplitude of the pendulum oscillations decreases more rapidly with softer coatings resulting in shorter damping times.

Examples 1 - 4 - Synthesis of Amine Adducts

The amine adducts (i.e., the adduct curing agents) were synthesized using the following general procedure; and using the amounts and compounds for the formulations described in Table I.

Acrylamide was charged into a flask at room temperature (about 25 °C), and then an amine compound was added to the flask. The resulting mixture was stirred under nitrogen until the acrylamide had totally dissolved. Then, polyacrylates were added into the flask and an exothermic reaction occurred immediately. Depending on the reactivity of the raw materials, an amount of catalyst, such as DBU, may be added to the composition. For example, a catalyst amount of from about 0.1 % to about 0.5 % can be used. After the temperature of the reaction mixture started to drop, the flask was heated to a temperature of 80 °C for a period of time of 2-3 hours until the C=C bond disappeared based on proton NMR measurements of samples of the reaction mixture. After 2-3 hours, the final reaction product (i.e., the adduct curing agent) was transfer to a glass bottle for use in a coating formulation.

The viscosity measurements of the prepared adduct curing agent is described in Table II.

Table I - Formulations for Preparing Amine Adducts

Table II - Viscosity of the Prepared Hardeners

Examples 5 - 8 and Comparative Example A - Synthesis of Coating Formulations and Coatings

The prepared amine hardeners from Examples 1-4 were evaluated by blending the prepared amine hardeners with an epoxy resin, DER331, to form clear coat formulations as described in Table III. NBDA (Comparative Example A) was used as a comparison. The mixing was conducted with a high speed mixture at 1500-2000 rpm at room temperature for 1 min. Table III - Coating Formulations

Examples 9 - 12 and Comparative Example B - Preparation of Coatings

The clear coat formulations from Examples 5-8 and Comparative Example A were cured to produce clear coatings (Examples 9-12 and Comparative Example B). The coatings were prepared using the following general procedure: charge the adduct curing agent and 10 % xylene solvent based on total weight into a given amount of epoxy resin with 1/1 of epoxy/amine equivalent weight ratio and mixed with a high speed mixer at 1500-2000 rpm speed for 1 minute. Then the formulated coating mixture was coated onto metal panel with a 6 mil drawdown bar and dried at a control room (25 °C, 50 % humidity) for 7 days.

The curing property of the coatings prepared as described above was evaluated by measuring dry time, gloss, and hardness development. The stoichiometry of NH/epoxy was 1/1 for all the Examples. The results are described in Tables IV, V and VI.

Table IV - Coating Curing Property and Coating Appearance

Table V - Coating Koenig Hardness

Table VI - Clear Coating Performance

Notes for Table VI: 5 is the best; 0 is the worst

5

Claims

WHAT IS CLAIMED IS:

1. A curing agent adduct composition for curing epoxy resins, said adduct composition comprising an adduct reaction product of (a) at least one polyamine compound, (b) at least one alpha beta unsaturated acrylate compound, and (c) at least one alpha beta unsaturated amide compound.

2. The adduct composition of claim 1, wherein the at least one polyamine compound, component (a), when used to form the adduct reaction product, is an aliphatic polyamine, a cycloaliphatic polyamine, or a mixture thereof.

3. The adduct composition of claim 1, wherein the at least one polyamine compound, component (a), when used to form the adduct reaction product, is an aliphatic diamine, a cycloaliphatic diamine, or a mixture thereof.

4. The adduct composition of claim 1, wherein the concentration of the at least one polyamine compound, component (a), when used to form the adduct reaction product, is from about 40 weight percent to about 95 weight percent based on the total compounds in the composition.

5. The adduct composition of claim 1, wherein the at least one alpha beta unsaturated acrylate compound, component (b), when used to form the adduct reaction product, is a (meth)acrylate compound.

6. The adduct composition of claim 1, wherein the at least one alpha beta unsaturated acrylate compound, component (b), when used to form the adduct reaction product, is an alkyl (meth)acrylate, an alkylene di(meth)acrylate, a poly glycol

di(meth)acrylate, a multi-functional (meth)acrylate, or a mixture thereof.

7. The adduct composition of claim 1, wherein the concentration of the at least one alpha beta unsaturated acrylate compound, component (b), when used to form the adduct reaction product, is from about 5 weight percent to about 40 weight percent based on the total compounds in the composition.

8. The adduct composition of claim 1 wherein the at least one alpha beta unsaturated amide compound, component (c), when used to form the adduct reaction product, is a (meth)acrylamide compound.

9. The adduct composition of claim 1, wherein the at least one alpha beta unsaturated amide compound, component (c), when used to form the adduct reaction product, is a (meth)acrylamide, a maleic amide, or a mixture thereof.

10. The adduct composition of claim 1, wherein the concentration of the at least one alpha beta unsaturated amide compound, component (c), when used to form the adduct reaction product, is from about 0.1 weight percent to about 20 weight percent.

11. The adduct composition of claim 1, wherein the stoichiometric ratio of the amine functionality (of component (a)) to the amide functionality (of component (c)) is from about 25 : 1 to about 5:1.

12. The adduct composition of claim 1, wherein the stoichiometric ratio of the amine functionality (of component (a)) to the acrylic functionality (of component (b)) is from about 25 : 1 to about 5:1.

13. The adduct composition of claim 1, including further at least one catalyst compound, component (d), used to form the adduct reaction product.

14. The adduct composition of claim 13, wherein the at least one catalyst compound, component (d), when used to form the adduct reaction product, is

l,8-diazabicyclo[5.4.0]undec-7-ene, Triethylamine (TEA), another tertiary amine catalyst, or mixtures thereof.

15. A process for preparing a curing agent adduct composition comprising reacting (a) at least one polyamine compound, (b) at least one alpha beta unsaturated acrylate compound, and (c) at least one alpha beta unsaturated amide compound.

16. A curable epoxy resin composition comprising (i) the adduct composition of claim 1 and (ii) at least one epoxy thermosetting resin.

17. The adduct composition of claim 1, including further (iii) at least one co-curing agent different from the adduct composition of claim 1.

18. A cured article comprising a product prepared by curing the curable epoxy resin composition of claim 16.

19. The cured article of claim 18, wherein the cured article exhibits no blooming; or wherein the cured article exhibits no blushing.

20. The cured article of claim 18, wherein the chemical resistance of the cured article is from greater than or equal to 4 as measured on a scale of from 1 to 5.

21. The cured article of claim 18, wherein the cured article is a coating, an adhesive, or a composite.