RU2839050C1 - Thermosetting resin compositions - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to thermosetting materials and relates to a curable resin composition and its preparation, which can be used in various versions of coatings, especially those which provide for high-temperature operating conditions. Curable resin composition contains a thermosetting resin, a reinforcing component containing a multiphase polymer and a thermoplastic reinforcing agent, which is a polyether sulphone and a phenylindanediamine hardener, wherein the resin composition has a glass transition temperature during curing of more than 150 °C.

EFFECT: invention provides the use of reinforcing components and hardeners with thermosetting materials, which, being cured, enabling the hardened product to reach a high glass transition temperature and exhibit mechanical and chemical properties which are especially suitable for use as coatings for various substrates exposed to severe operating conditions.

16 cl, 3 tbl

Description

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63/066,335, filed August 17, 2020, the entire contents of which are expressly incorporated herein by reference.

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

[0002] The present invention generally relates to curable resin compositions having a high glass transition temperature, increased impact strength and excellent thermal oxidation resistance and hydrolytic stability characteristics. The curable resin composition is particularly suitable for use as a coating in industrial applications, for the automotive industry and in electronic devices, and especially in those that involve high-temperature operating conditions.

LEVEL OF TECHNOLOGY

[0003] Thermosetting materials such as cured epoxy resins are known for their thermal and chemical stability. They also exhibit good mechanical properties, but often lack impact strength and tend to be very brittle. This is especially the case as their crosslinking density increases or the monomer functionality increases above two. Attempts have been made to strengthen or make tougher epoxy resins and other thermosetting materials such as bismaleimide resins, benzoxazine resins, cyanate ester resins, epoxy vinyl ester resins, and unsaturated ester resins by incorporating a variety of reinforcing materials into them.

[0004] Such reinforcements can be compared with each other by their structural, morphological or thermal characteristics. The structural framework of the reinforcement can be aromatic, aliphatic, or both aromatic and aliphatic. Aromatic reinforcements, such as polyetheretherketones or polyimides, create thermosetting materials that exhibit desirable improvements in terms of reinforcement, namely, impact compression, and, due to the aromatic structure of the reinforcement, low moisture absorption when exposed to hot, humid environments. In contrast, aliphatic reinforcements, such as nylon (also known as polyamide), create thermosetting materials that exhibit significant improvements in impact compression, but higher than desirable moisture absorption when exposed to hot, humid environments, which can lead to a decrease in compressive strength and bulk modulus. Other tougheners, such as core-shell polymers, can create thermosets that exhibit good damage resistance. However, these tougheners tend to have a negative effect on the processability and glass transition temperature of the thermoset.

[0005] One particular toughener that has recently found use in thermosetting resin compositions is a multi-stage (multi-phase) polymer, such as the polymers described in patent documents WO2016102666, WO2016102658, WO2016102682, WO2017211889, WO2017220793, WO2018002259 and WO2019012052. While these tougheners have been found to be easily dispersible in the thermosetting matrix to achieve a uniform distribution, the cured products may still lack adequate impact strength and chemical properties.

[0006] There is therefore a need for a further improvement over the prior art using reinforcing components and hardeners with thermosetting materials which, when cured, enable the cured product to achieve a high glass transition temperature and exhibit mechanical and chemical properties that are particularly suitable for use as coatings for various substrates exposed to harsh operating conditions.

ESSENCE OF THE INVENTION

[0007] The present invention generally provides a curable resin composition comprising (a) a thermosetting resin, (b) a reinforcing component comprising a multiphase polymer and a thermoplastic reinforcing agent, and (c) a phenylindanediamine curing agent. The curable resin composition can be used in a variety of applications, including those requiring the composition to exhibit, upon rapid curing, a glass transition temperature of at least 150°C, increased impact strength, and characteristics of high thermal oxidation resistance and hydrolytic stability. Thus, the curable resin composition is particularly suitable for use as a coating on process pipelines (e.g., for chemical and gas and oil industries), construction applications, and electronic devices, or other industrial applications.

DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention generally provides a curable resin composition comprising (a) a thermosetting resin, (b) a toughening component comprising a multiphase polymer and a thermoplastic toughener, and (c) a phenylindanediamine hardener. It has been unexpectedly found that the combination of the multiphase polymer and the thermoplastic toughener together with the phenylindanediamine hardener exhibits a synergistic effect such that the observed toughening effect is more pronounced than would be expected from the cured coating, as well as when forming it, which exhibits excellent thermal oxidation resistance and hydrolytic stability characteristics. The curable resin compositions described below exhibit high temperature resistance characteristics in both aqueous and dry environments, which are necessary for advanced high-temperature applications. The coatings obtained by curing the curable resin compositions also exhibit a glass transition temperature Tg>150°C, and preferably Tg>170°C, and most preferably Tg>190°C.

[0009] The following terms shall have the following meanings:

[0010] The term "curing," "cured," or similar terms, "curing," or "vulcanization," means the hardening of a thermosetting resin by chemical crosslinking. The term "curable" means that the composition is capable of being exposed to conditions that will cause the composition to be in a cured or thermosetting state or condition.

[0011] The term "multi-stage (multi-phase) polymer" means a polymer formed by a sequential multi-stage polymerization process. The multi-stage polymerization process may be a multi-stage emulsion polymerization process in which the first polymer is a first-stage polymer and the second polymer is a second-stage polymer (i.e., the second polymer is formed by emulsion polymerization in the presence of the first emulsion polymer).

[0012] The term "(meth)acrylic polymer" means that the (meth)acrylic polymer includes mainly polymers including (meth)acrylic monomers that constitute up to 50% by weight or more of the (meth)acrylic polymer.

[0013] The term "comprising" and its derivatives are not intended to exclude the presence of any additional component, step or procedure, whether the same or different from those disclosed herein. For the avoidance of any doubt, all compositions claimed herein by the use of the term "comprising" may include any additional additive or components unless otherwise specified. Conversely, the term "consisting essentially of," when used herein, excludes from the scope of any subsequent reference any other component, step or procedure, except those that are not essential to operability, and the term "consisting of," when used, excludes any component, step or procedure not specifically depicted or listed. The term "or," unless otherwise specified, refers to the members listed individually as well as in any combination.

[0014] The articles "a" and "an" are used here to denote one or more than one (i.e., at least one) grammatical object of the article. As an example, "epoxy resin" refers to one epoxy resin or more than one epoxy resin.

[0015] The expressions "in one embodiment," "according to one embodiment," and the like generally mean a specific feature, structure, or characteristic following the expression that is included in at least one aspect of the present invention, and may be included in more than one embodiment of the present invention. It is important to note that such expressions do not necessarily imply the same embodiment.

[0016] If a description identifies a component or feature as "allows," "may," "could," or "may," includes or has a characteristic, that particular component or feature need not necessarily include or have that characteristic.

[0017] The term "about" as used herein may allow for the possibility of a degree of variability in the value or range, such as being within 10%, within 5%, or within 1% of the stated value or stated range limit.

[0018] Values expressed in range format should be interpreted flexibly to include not only the numerical values specifically stated as the limits of the range, but also to include all individual numerical values or subranges within that range, as if each numerical value or subrange were specifically stated. For example, a range such as 1 to 6 should be considered to have specifically disclosed subranges such as 1 to 3, 2 to 4, 3 to 6, etc., as well as individual numbers within that range, such as 1, 2, 3, 4, 5, and 6. This applies regardless of the width of the range.

[0019] The terms "preferred" and "preferably" refer to embodiments that may provide certain advantages in certain circumstances. However, other embodiments may also be preferred in the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and does not imply the exclusion of other embodiments from the scope of the present invention.

[0020] According to a first embodiment, the present invention provides a curable resin composition that mainly comprises (a) a thermosetting resin, (b) a reinforcing component comprising a multiphase polymer and a thermoplastic reinforcing agent, and (c) a phenylindanediamine curing agent.

[0021] In one embodiment, the thermosetting resin may be an epoxy resin, a bismaleimide resin, a benzoxazine resin, a cyanate ester resin, a phenolic resin, a vinyl ester resin, or a mixture thereof. In one particular embodiment, the thermosetting resin is an epoxy resin.

[0022] In general, any epoxy group-containing compound is suitable for use as the epoxy resin in the present invention, such as the epoxy group-containing compounds disclosed in U.S. Patent No. 5,476,748, which is incorporated herein by reference. According to one embodiment, the epoxy resin is selected from a monofunctional epoxy resin, a difunctional epoxy resin (thereby having two epoxy groups), a trifunctional epoxy resin (thereby having three epoxy groups), a tetrafunctional epoxy resin (thereby having four epoxy groups), and mixtures thereof.

[0023] Illustrative, non-limiting examples of monofunctional epoxy resins include: styrene oxide, cyclohexene oxide, and glycidyl ethers of phenol, cresols, tert-butylphenol and other alkylphenols, butanol, 2-ethylhexanol, and C ₈ -C ₁₄ alcohols, and the like.

[0024] Illustrative non-limiting examples of bifunctional epoxy resins include: diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, diglycidyl ether of tetrabromobisphenol A, diglycidyl ether of propylene glycol, diglycidyl ether of butylene glycol, diglycidyl ether of ethylene glycol, diglycidyl ether of neopentyl glycol, diglycidyl ether of 1,4-butanediol, diglycidyl ether of 1,6-hexanediol, diglycidyl ether of cyclohexanedimethanol, diglycidyl ether of polyethylene glycol, diglycidyl ether of polypropylene glycol, diglycidyl ether of polytetramethylene glycol, diglycidyl ether of resorcinol, diglycidyl ether of neopentyl glycol, diglycidyl ether of bisphenol A-polyethylene glycol, diglycidyl ether of bisphenol A-polypropylene glycol, 3,4-epoxycyclohexyl methyl carboxylate, diglycidyl ester of hexahydrophthalic acid, diglycidyl ester of methylhexahydrophthalic acid, and mixtures thereof. In some embodiments, the bifunctional epoxy resin can be modified with a monofunctional reactive diluent such as, but not limited to, glycidyl ether of para-tert-butylphenol, glycidyl ether of cresol, 2-ethylhexyl glycidyl ether, and C ₈ -C ₁₄ -glycidyl ether.

[0025] Illustrative, non-limiting examples of trifunctional epoxy resins include: triglycidyl ether of para-aminophenol, triglycidyl ether of meta-aminophenol, dicyclopentadiene-based epoxy resins, N,N,O-triglycidyl-4-amino-meta- or -5-amino-ortho-cresol-type epoxy resins, and 1,1,1-(triglycidyloxyphenyl)methane-type epoxy resins.

[0026] Illustrative, non-limiting examples of tetrafunctional epoxy resins include: N,N,N',N'-tetraglycidylmethylenedianiline, N,N,N',N'-tetraglycidyl-meta-xylylenediamine, tetraglycidyldiaminodiphenylmethane, polyglycidyl ether of sorbitan, tetraglycidyl ether of pentaerythritol, tetraglycidyl-bis-aminomethylcyclohexane, and tetraglycidylglycoluril.

[0027] Examples of commercially available epoxy resins that can be used include, but are not limited to, ARALDITE® PY 306 epoxy resin (an unmodified liquid epoxy resin based on bisphenol-F), ARALDITE® MY 721 epoxy resin (a tetrafunctional epoxy resin based on methylenedianiline), ARALDITE® MY 0510 epoxy resin (a trifunctional epoxy resin based on para-aminophenol), ARALDITE® GY 6005 epoxy resin (a liquid epoxy resin based on bisphenol-A modified with a monofunctional reactive diluent), ARALDITE® 6010 epoxy resin (a liquid epoxy resin based on bisphenol-A), ARALDITE® MY 06010 resin (a trifunctional epoxy resin based on meta-aminophenol), ARALDITE® GY 285 epoxy resin (an unmodified liquid epoxy resin based on bisphenol-F), ARALDITE® EPN 1138, 1139 and 1180 epoxy resins (phenolic volac epoxy resins), ARALDITE® ECN 1273 and 9611 epoxy resins (cresol novolac epoxy resins), ARALDITE® GY 289 epoxy resin (phenolic volac epoxy resin), ARALDITE® PY 307-1 epoxy resin (phenolic volac epoxy resin), and mixtures thereof.

[0028] In one embodiment, the amount of epoxy resin present in the curable resin composition can be an amount between about 10 wt. % and about 95 wt. %, or between about 20 wt. % and about 75 wt. %, or between about 30 wt. % and about 60 wt. %, or between about 40 wt. % and about 50 wt. %, based on the total weight of the curable resin composition. In another embodiment, the amount of epoxy resin present in the curable resin composition can be an amount between about 50 wt. % and about 95 wt. %, or between about 65 wt. % and about 90 wt. %, based on the total weight of the curable resin composition.

[0029] In yet another further embodiment, the epoxy resin may consist of at least one trifunctional epoxy resin or tetrafunctional epoxy resin, or a mixture thereof, and, optionally, at least one difunctional epoxy resin. In such embodiments, the trifunctional epoxy resin may be present in the curable resin composition in an amount between about 25 wt. % and about 50 wt. %, or between about 35 wt. % and about 45 wt. %, based on the total weight of the curable resin composition, and the tetrafunctional epoxy resin may be present in the curable resin composition in an amount between about 1 wt. % and 20 wt. %, or between about 5 wt. % and 15 wt. %, based on the total weight of the curable resin composition.

[0030] According to another embodiment, the thermosetting resin is a benzoxazine resin. The benzoxazine resin can be any curable monomer, oligomer, or polymer containing at least one benzoxazine moiety. Thus, in one embodiment, the benzoxazine can be represented by the general formula (1)

,

wherein b is an integer from 1 to 4; each R independently represents a hydrogen atom, a substituted or unsubstituted _C1 - _C20 alkyl group, a substituted or unsubstituted _C2 - _C20 alkenyl group, a substituted or unsubstituted _C6 - _C20 aryl group, a substituted or unsubstituted _C2 - _C20 heteroaryl group, a substituted or unsubstituted _C4 - _C20 carbocyclic group, a substituted or unsubstituted _C2 - _C20 heterocyclic group, or a _C3 - _C8 cycloalkyl group; each R ₁ independently represents a hydrogen atom, a _C1 - _C20 alkyl group, a _C2 - _C20 alkenyl group, or a _C6 - _C20 aryl group; and Z represents a single bond (when b=2), a substituted or unsubstituted _C1 - _C20 alkyl group, a substituted or unsubstituted _C6 - _C20 aryl group, a substituted or unsubstituted _C2 - _C20 heteroaryl group, O, S, S=O, O=S=O or C=O. Substituents include, but are not limited to, a hydroxy group, a _C1 - _C20 alkyl group, a _C2 - _C20 alkoxy group, a mercapto group, a _C3 - _C8 cycloalkyl group, a _C6 - _C14 heterocyclic group, a _C6 - _C14 aryl group, a _C6 - _C14 heteroaryl group, a halogen atom, a cyano group, a nitro group, a nitrone group, an amino group, an amide group, an acyl, an oxyacyl, a carboxyl, a carbamate, a sulfonyl, a sulfonamide, and a sulfuryl group.

[0031] In one particular embodiment within formula (1), the benzoxazine may be represented by the general formula (1a)

where Z is selected from a single bond, CH ₂ , C(CH ₃ ) ₂ , C=O, O, S, S=O, O=S=O, and

,

each R independently represents a hydrogen atom, a C ₁ -C ₂₀ alkyl group, an allyl group, or a C ₆ -C ₁₄ aryl group; and R ₁ is as defined above.

[0032] In another embodiment, benzoxazine can be represented by the following general formula (2)

,

wherein Y represents a _C1 - _C20 alkyl group, a _C2 - _C20 alkenyl group, or a substituted or unsubstituted phenyl group; and each _R2 independently represents a hydrogen atom, a halogen atom, a _C1 - _C20 alkyl group, a _C2 - _C20 alkenyl group, or a _C6 - _C20 aryl group. Suitable substituents for the phenyl group are as set out above.

[0033] In one particular embodiment, within the scope of formula (2), the benzoxazine may be represented by the following formula (2a)

,

wherein each R ₂ independently represents a C ₁ -C ₂₀ alkyl or C ₂ -C ₂₀ alkenyl group, each of which is optionally substituted by or comprises in the chains one or more O, N, S atoms, C=O, COO and NHC=O groups, and a C ₆ -C ₂₀ aryl group; and each R ₃ independently represents a hydrogen atom, a C ₁ -C ₂₀ alkyl or C ₂ -C ₂₀ alkenyl group, each of which is optionally substituted by or comprises in the chains one or more O, N, S atoms, C=O, COOH and NHC=O groups, or a C ₆ -C ₂₀ aryl group.

[0034] Alternatively, benzoxazine may be represented by the following general formula (3)

,

where p is 2; W is selected from diphenyl, diphenylmethane, diphenylisopropane, diphenyl sulfide, diphenyl sulfoxide, diphenyl sulfone and diphenyl ketone; and R ¹ is as defined above.

[0035] Benzoxazines are commercially available from several suppliers, including Huntsman Advanced Materials Americas LLC, Georgia Pacific Resins Inc., and Shikoku Chemicals Corporation.

[0036] Benzoxazines can also be prepared by reacting a phenolic derivative, such as bisphenol A, bisphenol F, or phenolphthalein, with an aldehyde, such as formaldehyde, and a primary amine under conditions that remove water. The molar ratio of the phenolic derivative to the aldehyde reactant can be from about 1:3 to 1:10, alternatively from about 1:4 to 1:7. In yet another further embodiment, the molar ratio of the phenolic derivative to the aldehyde reactant can be from about 1:4.5 to 1:5. The molar ratio of the phenolic derivative to the primary amine reactant can be from about 1:1 to 1:3, alternatively from about 1:1.4 to 1:2.5. In yet another further embodiment, the molar ratio of the phenolic derivative to the primary amine reactant may be from about 1:2.1 to 1:2.2.

[0037] Examples of primary amines include: aromatic mono- or diamines, aliphatic amines, cycloaliphatic amines, and heterocyclic monoamines such as aniline, ortho-, meta-, and para-phenylenediamine, benzidine, 4,4'-diaminodiphenylmethane, cyclohexylamine, butylamine, methylamine, hexylamine, allylamine, furfurylamine, ethylenediamine, and propylenediamine. The amines, at their corresponding carbon moiety, may be substituted with a C ₁ -C ₈ alkyl or allyl group. In one embodiment, the primary amine is a compound having the general formula R _a NH ₂ , wherein R _a is allyl, unsubstituted or substituted phenyl, unsubstituted or substituted C ₁ -C ₈ alkyl, or C ₃ -C ₈ cycloalkyl. Suitable substituents on the R _a group include, but are not limited to, amino, C ₁ -C ₄ alkyl, or allyl. In some embodiments, one to four substituents may be present on the R _a group. In one particular embodiment, R _a is phenyl.

[0038] According to one embodiment, the benzoxazine may be present in the curable composition in an amount in the range of between about 10 wt. % and about 90 wt. %, based on the total weight of the curable composition. In another embodiment, the benzoxazine may be present in the curable composition in an amount in the range of between about 60 wt. % and about 90 wt. %, based on the total weight of the curable composition.

[0039] The curable resin composition also includes a reinforcing component comprising a multiphase polymer and a thermoplastic reinforcing agent.

[0040] A multiphase polymer (for example as described in patent documents WO2016/102411 and WO2016/102682, the contents of which are incorporated herein by reference) has at least two phases that differ in their polymer composition, wherein the first phase forms the core and the second or all subsequent phases form the respective shells. The multiphase polymer may be in the form of polymer particles, in particular spherical particles. These polymer particles are also referred to as core-shell particles, with the first phase constituting the core and the second and all subsequent phases forming the respective shells. In one embodiment, the polymer particles may have a weight average particle size between 20 nm and 800 nm, or between 25 nm and 600 nm, or between 30 nm and 550 nm, or between 40 nm and 400 nm, or between 75 nm and 350 nm, or between 80 nm and 300 nm. The polymer particles may be agglomerated to form a polymer powder.

[0041] Thus, the polymer particles can have a multilayer structure comprising at least one layer (or phase) (A) comprising a polymer (A1) having a glass transition temperature lower than about 10°C, and at least one more layer (or phase) (B) comprising a polymer (B1) having a glass transition temperature higher than about 30°C. In some embodiments, the polymer (B1) is an outer layer of the polymer particle. In other embodiments, the phase (A) comprising the polymer (A1) is a first phase, and the phase (B) comprising the polymer (B1) is grafted onto the phase (A) comprising the polymer (A1).

[0042] As noted above, the polymer particle may be produced by a multi-stage process, such as a process comprising two, three or more stages. The polymer (A1) having a glass transition temperature lower than about 10°C in the layer (A) is never formed during the last stage of the multi-stage process. This means that the polymer (A1) is never in the outer layer of the particle. Accordingly, the polymer (A1) having a glass transition temperature lower than about 10°C in the layer (A) constitutes either the core of the polymer particle or one of the inner layers.

[0043] In some embodiments, the polymer (A1) having a glass transition temperature lower than about 10°C is formed in layer (A) in a first stage of a multi-stage process that forms the core of a polymer particle having a multilayer structure and/or before the polymer (B1).

[0044] In other embodiments, the polymer (B1) having a glass transition temperature above about 30°C is formed in the last stage of a multi-stage process that forms the outer layer of the polymer particle. There could be additional intermediate layer or layers obtained in an intermediate stage or in intermediate stages.

[0045] In one embodiment, at least a portion of the polymer (B1) of the layer (B) is grafted onto the polymer formed in the preceding layer. If there are only two phases (A) and (B), comprising polymer (A1) and (B1), respectively, a portion of the polymer (B1) is grafted onto the polymer (A1). In some embodiments, at least 50 wt. % of the polymer (B1) is grafted.

[0046] According to one embodiment, polymer (A1) is a (meth)acrylate polymer comprising at least 50 wt. % alkyl acrylates monomers. In further embodiments, polymer (A1) comprises a comonomer or comonomers that can be copolymerized with the alkyl acrylate as long as polymer (A1) has a glass transition temperature lower than about 10°C. The comonomer or comonomers in polymer (A1) can be selected from (meth)acrylate monomers and/or vinyl monomers. The (meth)acrylate comonomers can include monomers selected from _C1 - _C12 -alkyl (meth)acrylates. In still other embodiments, the (meth)acrylate comonomer in the polymer (A1) comprises monomers from _C1 - _C4- alkyl (meth)acrylate and/or _C1 - _C8- alkyl acrylate monomers. The acrylic or methacrylic comonomers of the polymer (A1) are most preferably selected from methyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, tert-butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and mixtures thereof, as long as the polymer (A1) has a glass transition temperature of less than about 10°C.

[0047] In another embodiment, the polymer (A1) is crosslinked (i.e., a crosslinking agent is added to other monomer or monomers). The crosslinking agent may include at least two groups that can be polymerized.

[0048] In one particular embodiment, polymer (A1) is a homopolymer of butyl acrylate. In another particular embodiment, polymer (A1) is a copolymer of butyl acrylate and at least one crosslinking agent. The crosslinking agent may be present in an amount of less than 5 wt.% of the copolymer.

[0049] In yet another further embodiment, the polymer (A1) having a glass transition temperature lower than about 10°C is a polymer based on silicone rubber. For example, the silicone rubber may be polydimethylsiloxane.

[0050] In yet another further embodiment, the polymer (A1) having a glass transition temperature lower than about 10°C comprises at least 50 wt. % polymeric structural units derived from isoprene or butadiene, and the phase (A) constitutes the innermost layer of the polymer particle. In other words, the phase (A) comprising the polymer (A1) is the core of the polymer particle. By way of example, the core polymer (A1) can be formed from isoprene homopolymers or butadiene homopolymers, isoprene-butadiene copolymers, copolymers of isoprene with not more than 98 wt. % vinyl monomer, and copolymers of butadiene with not more than 98 wt. % vinyl monomer. The vinyl monomer can be styrene, alkyl styrene, acrylonitrile, alkyl (meth) acrylate, or butadiene or isoprene. In one embodiment, the core is composed of a butadiene homopolymer.

[0051] The polymer (B1) can be formed from homopolymers and copolymers comprising monomers with double bonds and/or vinyl monomers. The polymer (B1) is preferably a (meth)acrylic polymer. The polymer (B1) preferably comprises at least 70 wt. % of monomers selected from _C1 - _C12 -alkyl (meth)acrylates. Even more preferably, the polymer (B1) comprises at least 80 wt. % of monomers from _C1 - _C4- alkyl methacrylate and/or _C1 - _C8 -alkyl acrylate monomers. Most preferably, the acrylic or methacrylic monomers of the polymer (B1) are selected from methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and mixtures thereof, as long as the polymer (B1) has a glass transition temperature of at least about 30°C. The polymer (B1) advantageously comprises at least 70 wt.% of monomer structural units originating from methyl methacrylate.

[0052] In another embodiment, the multiphase polymer as previously described has an additional phase which is a (meth)acrylic polymer (P1). The primary polymer particle according to this embodiment will have a multilayer structure comprising at least one phase (A) comprising a polymer (A1) having a glass transition temperature lower than about 10°C, at least one phase (B) comprising a polymer (B1) having a glass transition temperature greater than about 30°C, and at least one phase (P) comprising a (meth)acrylic polymer (P1) having a glass transition temperature between about 30°C and about 150°C. The (meth)acrylic polymer (P1) is preferably not grafted onto any of the polymers (A1) or (B1).

[0053] The (meth)acrylic polymer (P1) may have a weight average molecular weight Mw of less than about 100,000 g/mol, or less than about 90,000 g/mol, or less than about 80,000 g/mol, or less than about 70,000 g/mol, preferably less than about 60,000 g/mol, more preferably less than about 50,000 g/mol, and even more preferably less than about 40,000 g/mol.

[0054] The (meth)acrylic polymer (P1) may have a weight average molecular weight Mw of greater than about 2000 g/mol, or greater than about 3000 g/mol, or greater than about 4000 g/mol, or greater than about 5000 g/mol, preferably greater than about 6000 g/mol, more preferably greater than about 6500 g/mol, and even more preferably greater than about 7000 g/mol, and most preferably greater than about 10000 g/mol.

[0055] The weight average molecular weight Mw of the (meth)acrylic polymer (P1) may be between about 2000 g/mol and about 100000 g/mol, or between about 3000 g/mol and about 90000 g/mol, or between about 4000 g/mol and about 80000 g/mol, preferably between about 5000 g/mol and about 70000 g/mol, more preferably between about 6000 g/mol and about 50000 g/mol, and most preferably between about 10000 g/mol and about 40000 g/mol.

[0056] The (meth)acrylic polymer (P1) is preferably a copolymer comprising (meth)acrylic monomers. The (meth)acrylic polymer (P1) is more preferably a (meth)acrylic polymer. Even more preferably, the (meth)acrylic polymer (P1) comprises at least 50 wt. % of monomers selected from C ₁ -C ₁₂ -alkyl (meth)acrylates. The (meth)acrylic polymer (P1) preferably comprises at least 50 wt. % of monomers selected from C ₁ -C ₄ -alkyl methacrylate and C ₁ -C ₈ -alkyl acrylate monomers and mixtures thereof. The (meth)acrylic polymer (P1) more preferably comprises at least 50 wt. % of polymerized methyl methacrylate, and even more preferably at least 60 wt. %, and most preferably at least 65 wt. % polymerized methyl methacrylate.

[0057] In one embodiment, the (meth)acrylic polymer (P1) comprises from 50 wt.% to 100 wt.% methyl methacrylate, or from 80 wt.% to 100 wt.% methyl methacrylate, or from 80 wt.% to 99.8 wt.% methyl methacrylate, and from 0.2 wt.% to 20 wt.% _C1 - _C8- alkyl acrylate monomer. The _C1 - _C8- alkyl acrylate monomer is preferably selected from methyl acrylate, ethyl acrylate or butyl acrylate.

[0058] In another embodiment, the (meth)acrylic polymer (P1) comprises between 0.01 wt.% and 50 wt.% of a functional monomer. The (meth)acrylic polymer (P1) preferably comprises between 0.01 wt.% and 30 wt.% of a functional monomer, more preferably between 1 wt.% and 30 wt.%, even more preferably between 2 wt.% and 30 wt.%, especially between 3 wt.% and 30 wt.% of a functional monomer.

[0059] In one embodiment, the functional monomer is selected from glycidyl (meth)acrylate, acrylic or methacrylic acid, amides formed from acrylic or methacrylic acids, such as, for example, dimethylacrylamide, 2-methoxyethyl acrylate or -methacrylate, 2-aminoethyl acrylates or -methacrylates, which are optionally quaternized, acrylate or methacrylate monomers comprising a phosphonate or phosphate group, alkylimidazolidinone (meth)acrylates, and polyethyleneglycol (meth)acrylates. The polyethyleneglycol group of the polyethyleneglycol (meth)acrylates preferably has a molecular weight in the range of from 400 g/mol to 10,000 g/mol.

[0060] In one embodiment, the reinforcing component also includes a thermoplastic reinforcement. In one embodiment, the thermoplastic reinforcement is a polyether sulfone. Non-limiting examples of polyether sulfones include the particulate polyether sulfones sold under the trade name Sumnikaexcel®, the polyether sulfones that are commercially available from Sumitomo Chemicals, and those polyether sulfones that are sold under the trade names Veradel® and Virantage® that are commercially available from Solvay Chemicals. Densified particles of polyether sulfones may also be used. The form of the polyether sulfone is not particularly critical, since the polyether sulfone may be dissolved during the formation of the curable resin composition. Densified particles of polyether sulfones may be formed in accordance with the teachings of U.S. Patent No. 4,945,154, the contents of which are hereby incorporated by reference herein. Densified polyethersulfone particles are also commercially available from Hexcel Corporation under the trade name HRI-1. In some embodiments, the average particle size of the polyethersulfone is less than 100 microns (µm) to promote and ensure complete dissolution of the polyethersulfone in the thermoset resin.

[0061] In another embodiment, the thermoplastic toughener may be any of the following thermoplastic polymers: polysulfone, polyetherimide, polyamide (PA), polyphenylene oxide (PPO), polyethylene oxide (PEO), phenoxy, polymethyl methacrylate (PMMA), polyvinylpyrrolidone (PVP), polyetheretherketone (PEEK), polystyrene (PS), polycarbonate (PC), or mixtures thereof. According to one embodiment, polyethersulfone is the only thermoplastic toughener included in the curable resin composition (i.e., the curable resin composition does not contain any other thermoplastic polymer toughening agents other than polyethersulfone).

[0062] According to one embodiment, the amount of the strengthening component present in the curable resin composition is less than about 25 weight percent, based on the total weight of the curable resin composition. In another embodiment, the amount of the strengthening component present in the curable resin composition is less than about 22.5 weight percent, or less than about 20 weight percent, or less than about 17.5 weight percent, or less than about 15 weight percent, based on the total weight of the curable resin composition. According to another embodiment, the amount of the strengthening component present in the curable resin composition is at least about 1 weight percent, or at least about 5 weight percent, or at least about 7.5 weight percent, based on the total weight of the curable resin composition. In yet another further embodiment, the amount of the strengthening component present in the curable resin composition is between about 1 wt. % and about 25 wt. %, or between about 5 wt. % and about 20 wt. %, or between about 7 wt. % and about 16 wt. %, based on the total weight of the curable resin composition. In yet another embodiment, the amount of the strengthening component present in the curable resin composition is between about 1 wt. % and about 15 wt. %, based on the total weight of the curable resin composition.

[0063] According to another embodiment, the amount of multiphase polymer present in the curable resin composition is between about 3 wt. % and about 20 wt. %, or between about 4 wt. % and about 15 wt. %, or from about 5 wt. % to about 10 wt. %, based on the total weight of the curable resin composition. In yet another embodiment, the amount of thermoplastic toughener present in the curable resin composition is between about 0.1 wt. % and about 10 wt. %, or between about 0.5 wt. % and about 8 wt. %, or between about 1 wt. % and about 7 wt. %, based on the total weight of the curable resin composition.

[0064] Curing of the curable resin composition can be accomplished by adding phenylindanediamine. In one embodiment, the phenylindanediamine is a compound having the structure

where R ² represents a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms; R ³ independently represents a hydrogen atom, a halogen atom, or an alkyl group having from 1 to 6 carbon atoms; and b independently represents an integer from 1 to 4, and the amino group in the indane ring is in position 5 or 6.

[0065] The phenylindanediamines may include any combination of isomeric or substituted isomeric derivatives of phenylindanediamines. For example, the phenylindanediamines may include from 0 mol% to 100 mol% 5-amino-3-(4'-aminophenyl)-1,1,3-trimethylindane in combination with from 100 mol% to 0 mol% 6-amino-3-(4'-aminophenyl)-1,1,3-trimethylindane. Furthermore, either or both of these isomers may be substituted within the entire range of 0 to 100% by any of the substituted diamine isomers. Examples of such substituted diamine isomers are 5-amino-6-methyl-3-(3'-amino-4'-methylphenyl)-1,1,3-trimethylindane, 5-amino-3-(4'-amino-Ar',Ar'-dichlorophenyl)-Ar, Ar-dichloro-1,1,3-trimethylindane, 6-amino-(4'-amino-Ar',Ar'-dichlorophenyl)-Ar, Ar-dichloro-1,1,3-trimethylindane, 4-amino-6-methyl-3-(3'-amino-4'-methylphenyl)-1,1,3-trimethylindane, and Ar-amino-3-(Ar'-amino-2',4'-dimethylphenyl)-1,1,3,4,6-pentamethylindane. The prefixes Ar and Ar’ in the above formulas denote unrestricted positions of these substituents in the phenyl rings.

[0066] Among the phenylindanediamines, there may be mentioned those in which R ² independently represents a hydrogen atom or methyl, and R ³ independently represents a hydrogen atom, a methyl group, a chlorine atom or bromine. Particularly suitable phenylindanediamines are those in which R ² represents a hydrogen atom or methyl, and R ³ independently represents a hydrogen atom, a methyl group, a chlorine atom or bromine, and the amino groups are in the 5- or 6-position and in the 3' or 4'-position. In view of their relative availability, phenylindanediamines which are particularly useful include compounds in which R ² represents methyl, each R ³ represents a hydrogen atom, and the amino groups are in the 5- or 6-position and in the 4'-position. These compounds are known as 5(6)-amino-3-(4'-aminophenyl)-1,1,3-trimethylindane (DAPI).

[0067] Phenylindanediamines and methods for preparing them are disclosed in U.S. Patent Nos. 385,652 and 3,983,092, which patents are incorporated herein by reference in their entirety for their subject matter relating to the preparation of such materials.

[0068] In addition to phenylindanediamine, other curing agents may also be included, such as, but not limited to, aromatic amines, cyclic amines, aliphatic amines, alkyl amines, polyetheramines, including such polyetheramines that may be derived from polypropylene oxide and/or polyethylene oxide, 9,9-bis(4-amino-3-chlorophenyl)fluorene (CAF), acid anhydrides, carboxylic acid amides, polyamides, polyphenols, cresol and phenolic resins, imidazoles, guanidines, substituted guanidines, substituted ureas, melamine resins, guanamine derivatives, tertiary amines, Lewis acid complexes such as boron trifluoride and boron trichloride, and polymercaptans. Any of the epoxy-modified amine products, modified Mannich reaction products, and modified Michael addition reaction products of the above-described curing agents may also be used. All of the above curing agents may be used either singly or in any combination.

[0069] Exemplary aromatic amines include, but are not limited to, 1,8-diaminonaphthalene, meta-phenylenediamine, diethylenetoluenediamine, diaminodiphenylsulfone, diaminodiphenylmethane, diaminodiethyldimethyldiphenylmethane, 4,4′-methylene-bis(2,6-diethylaniline), 4,4′-methylene-bis(2-isopropyl-6-methylaniline), 4,4′-methylene-bis(2,6-diisopropylaniline), 4,4′-[1,4-phenylene-bis(1-methylethylindene)]bisaniline, 4,4′-[1,3-phenylene-bis(1-methylethylindene)]bisaniline, 1,3-bis(3-aminophenoxy)benzene, bis-[4-(3-aminophenoxy)phenyl]sulfone, bis-[4-(4-aminophenoxy)phenyl]sulfone, 2,2′-bis[4-(4-aminophenoxy)phenyl]propane, and bis(4-amino-2-chloro-3,5-diethylphenyl)methane. Additionally, the aromatic amines may include adducts of heterocyclic polyfunctional amines as disclosed in U.S. Patent Nos. 4,427,802 and 4,599,413, both of which are hereby incorporated by reference in their entireties.

[0070] Examples of cyclic amines include, but are not limited to, bis(4-amino-3-methyldicyclohexyl)methane, diaminodicyclohexylmethane, bis(aminomethyl)cyclohexane, N-aminoethylpyrazine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, meta-xylylenediamine, isophoronediamine, menthenediamine, 1,4-bis(2-amino-2-methylpropyl)piperazine, N,N′-dimethylpiperazine, pyridine, picoline, 1,8-diazabicyclo[5,4,0]-7-undecene, benzylmethylamine, 2-(dimethylaminomethyl)phenol, 2-methylimidazole, 2-phenylimidazole, and 2-ethyl-4-methylimidazole.

[0071] Exemplary aliphatic amines include, but are not limited to, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 3-(dimethylamino)propylamine, 3-(diethylamino)propylamine, 3-(methylamino)propylamine, tris(2-aminoethyl)amine; 3-(2-ethylhexyloxy)propylamine, 3-ethoxypropylamine, 3-methoxypropylamine, 3-(dibutylamino)propylamine, and tetramethylethylenediamine; ethylenediamine; 3,3'-iminobis(propylamine), N-methyl-3,3'-iminobis(propylamine); allylamine, diallylamine, triallylamine, polyoxypropylenediamine, and polyoxypropylenetriamine.

[0072] Exemplary alkylamines include, but are not limited to, methylamine, ethylamine, propylamine, isopropylamine, butylamine, sec-butylamine, tert-butylamine, n-octylamine, 2-ethylhexylamine, dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, di-sec-butylamine, di-tert-butylamine, di-n-octylamine, and di-2-ethylhexylamine.

[0073] Exemplary acid anhydrides include, but are not limited to, cyclohexane-1,2-dicarboxylic anhydride, 1-cyclohexene-1,2-dicarboxylic anhydride, 2-cyclohexene-1,2-dicarboxylic anhydride, 3-cyclohexene-1,2-dicarboxylic anhydride, 4-cyclohexene-1,2-dicarboxylic anhydride, l-methyl-2-cyclohexene-1,2-dicarboxylic anhydride, 1-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, 3-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, 4-methyl-4-cyclohexene-1,2-dicarboxylic anhydride, dodecenyl succinic anhydride, succinic anhydride, 4-methyl-1-cyclohexene-1,2-dicarboxylic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylenedic anhydride, dodecenylsuccinic anhydride, tetrahydrophthalic anhydride, maleic anhydride, pyromellitic dianhydride, trimellitic anhydride, benzophenonetetracarboxylic dianhydride, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride, methyl-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic anhydride, dichloromaleic anhydride, chlorendic anhydride, tetrachlorophthalic anhydride, and any derivative or adduct thereof.

[0074] Exemplary imidazoles include, but are not limited to, imidazole, 1-methylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-n-propylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-isopropyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 1,2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-dodecyl-2-methylimidazole, and 1-cyanoethyl-2-phenyl-4,5-di(2-cyanoethoxy)methylimidazole.

[0075] Exemplary substituted guanidines are methylguanidine, dimethylguanidine, trimethylguanidine, tetramethylguanidine, methylisobiguanidine, dimethylisobiguanidine, tetramethylisobiguanidine, hexamethylisobiguanidine, heptamethylisobiguanidine, and cyanoguanidine (dicyandiamide). Representative guanamine derivatives that may be mentioned are alkylated benzoguanamine resins, benzoguanamine resins, or methoxymethylethoxymethylbenzoguanamine. Substituted ureas may include para-chlorophenyl-N,N-dimethylurea (monuron), 3-phenyl-1,1-dimethylurea (fenuron), or 3,4-dichlorophenyl-N,N-dimethylurea (diuron).

[0076] Exemplary tertiary amines include, but are not limited to, trimethylamine, tripropylamine, triisopropylamine, tributylamine, tri-sec-butylamine, tri-tert-butylamine, tri-n-octylamine, N,N-dimethylaniline, N,N-dimethylbenzylamine, pyridine, N-methylpiperidine, N-methylmorpholine, N,N-dimethylaminopyridine, morpholine derivatives such as bis(2-(2,6-dimethyl-4-morpholino)ethyl)-(2-(4-morpholino)ethyl)amine, bis(2-(2,6-dimethyl-4-morpholino)ethyl)-(2-(2,6-diethyl-4-morpholino)ethyl)amine, tris(2-(4-morpholino)ethyl)amine, and tris(2-(4-morpholino)propyl)amine, diazabicyclooctane (DABCO), and heterocyclic compounds having an amidine linkage such as the diazabicyclone moiety.

[0077] Amine epoxide adducts are well known in the art and are described, for example, in U.S. Patent Nos. 3,756,984, 4,066,625, 4,268,656, 4,360,649, 4,542,202, 4,546,155, 5,134,239, 5,407,978, 5,543,486, 5,548,058, 5,430,112, 5,464,910, 5,439,977, 5,717,011, 5,733,954, 5,789,498, 5,798,399, and 5,801,218, each of which is incorporated herein by reference in its entirety. Such aminoepoxy adducts are reaction products between one or more amine compounds and one or more epoxy derivatives. The adduct is preferably a solid that is insoluble in the epoxy resin at room temperature, but which becomes soluble and acts as a catalyst to enhance the rate of cure upon heating. While any type of amine can be used (with heterocyclic amines and/or amines containing at least one secondary nitrogen atom being preferred), imidazole derivatives are particularly preferred. Illustrative examples of imidazoles include 2-methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and the like. Other suitable amines include, but are not limited to, piperazines, piperidines, pyrazoles, purines, and triazoles. As another starting material for the adduct, any type of epoxy compound can be used, including monofunctional and polyfunctional epoxy compounds such as those described previously with respect to the epoxy resin component.

[0078] In one embodiment, the curable resin composition of the present invention may comprise a phenylindanediamine curing agent in an amount between about 5 wt. % and about 50 wt. %, or between about 20 wt. % and about 50 wt. %, or between about 40 wt. % and about 50 wt. %, based on the total weight of the curable resin composition.

[0079] In yet another further embodiment, the curable resin composition may also contain one or more other additives that are useful for its intended use. For example, optional additives may include, but are not limited to, diluents, stabilizers, surfactants, flow modifiers, release agents, matting agents, degassing agents, thermoplastic particles (e.g., liquid carboxyl-terminated butadiene-acrylonitrile rubber (CTBN), liquid acrylic-terminated butadiene-acrylonitrile rubber (ATBN), liquid epoxy-terminated butadiene-acrylonitrile rubber (ETBN), liquid epoxy resin adducts (LER) of elastomers and preformed core-shell rubbers), cure initiators, cure inhibitors, wetting agents, processing aids, fluorescent compounds, UV stabilizers, antioxidants, impact modifiers, corrosion inhibitors, tackifiers, high-density particulate fillers (e.g., various naturally occurring clays such as kaolin, bentonite, montmorillonite or modified montmorillonite, attapulgate, and Buckminster Fuller's earth; other naturally occurring materials or formed from them such as mica, calcium carbonate, and aluminum carbonate; various oxides such as iron oxide, titanium dioxide, calcium oxide, and silica (e.g., sand); various artificial materials such as precipitated calcium carbonate; and various wastes such as ground blast furnace slag), conductive particles (e.g., silver, gold, copper, nickel, aluminum, and conductive grades of carbon and carbon nanotubes), and mixtures thereof.

[0080] The amount of additives, if present, introduced into the curable resin composition can be at least about 0.5 wt. %, or at least 2 wt. %, or at least 5 wt. %, or at least 10 wt. %, based on the total weight of the curable resin composition. In other embodiments, the amount of additives present in the curable resin composition can be no more than about 30 wt. %, or no more than 25 wt. %, or no more than 20 wt. %, or no more than 15 wt. %, based on the total weight of the curable resin composition.

[0081] The curable resin composition can be prepared, for example, by pre-mixing the individual components and then mixing these pre-mixtures, or by mixing all of the components together using conventional devices such as a stirred tank, a rod stirrer, a ball mill, a sample mixer, a static mixer, a high shear mixer, a ribbon mixer, or by hot melting.

[0082] Thus, according to another embodiment, the curable resin composition according to the present invention can be obtained by mixing together from about 10 wt. % to about 95 wt. % of a thermosetting resin and from about 1 wt. % to about 15 wt. % of a reinforcing component, and from about 5 wt. % to about 50 wt. % of a hardener, where the value in wt. % is given based on the total weight of the curable resin composition.

[0083] According to another embodiment, a curable resin composition can be applied to a substrate to coat at least a portion (or substantially all) of the substrate, and then cured by heating at a temperature greater than about 80°C to form a coated substrate. The curable resin composition can be applied by any known method, such as spraying, dipping, fluidized bed, etc. In another embodiment, after application, the curable resin composition can be cured by heating at a temperature in the range of about 80°C to about 180°C, preferably about 100°C to about 160°C. Heating can be accomplished by any method known in the art, such as placing the coated substrate in an oven. IR radiation can also be used to thermally cure the coated substrate. The powder coated surface should be subjected to curing temperatures for a period of time sufficient to cure the composition to form a substantially continuous, uniform coating. Typically, curing for a period of from about 1 minute to about 10 minutes or more will convert the composition into a substantially continuous, uniform coating. If desired, curing can be carried out in two or more stages, such as partially curing at a lower temperature, then fully curing at an elevated temperature. In yet another further embodiment, the curable resin composition can reach 85% of the fully cured state within 5 minutes, preferably within 2 minutes, more preferably within 1 minute, and most preferably within 45 seconds, when curing is carried out at a temperature in the range between about 80 ° C and about 160 ° C.

[0084] In another embodiment, the thermally curable resin composition, when mixed and cured, creates a film having a glass transition temperature greater than 150°C, preferably greater than 170°C, most preferably greater than 180°C, and particularly preferably greater than 190°C.

[0085] The curable resin composition of the present invention can be used in various applications such as casting, laminating, impregnating, coating, adhering, sealing, painting, bonding, insulating, or in embedding, pressing, injection molding, extrusion, sand mold fixing, foaming and ablative materials.

[0086] According to some embodiments, the thermally curable resin composition can be used in the production of and/or as a sealant, adhesive, or coating. The sealant, adhesive, or coating comprising the curable resin composition can be applied to a surface (internal or external, or both) of one or more substrates and heated to form a cured film. The substrate can be metallic or non-metallic. Examples of substrates include metallic pipelines, such as those used in the transportation of various chemical materials such as those common in the chemical and oil and gas industries, silicate, metal oxide, concrete, wood, plastic, cardboard, particle board, ceramic materials, glass, graphite, cellulosic materials, electronic integrated circuit materials, and semiconductor materials. In some embodiments, the substrates include the inner and/or outer surfaces of steel pipes, structural steel used in concrete or in marine environments, storage tanks, valves and pipelines and casings in oil and gas production. If desired, before or after application of the curable resin composition, the surface of the substrate can be subjected to mechanical treatment, such as shot blasting, followed, in the case of metal substrates, by acid washing, or cleaning and then chemical treatment. In addition, the substrate to be coated can be preheated before application of the powder composition.

[0087] In embodiments where the curable resin composition is used as a coating, it can be used in a single coating system or as a topcoat in forming a multilayer film. The curable resin composition of the invention can be applied directly to the substrate surface or to a primer layer, which can be a liquid or a powder-based primer. The curable resin composition of the invention can also be applied as a topcoat in a multilayer coating system based on liquid or powder coatings, for example, based on a powder or liquid clear topcoat applied to a color-imparting and/or special-effect base coat, or as a pigmented single-layer powder or liquid topcoat applied to a primary coating. The curable resin composition may be applied to the substrate by a known method such as spraying, dipping, flowing, rolling, etc., in a single pass or in multiple passes. After application, the coating applied to the surface of the substrate is then heated at a temperature sufficient to cure the composition and form a film-coated substrate. In some embodiments, the film coating will typically have a thickness after curing of about 1 to 10 mils (0.025-0.25 mm), preferably about 2-4 mils (0.05-0.1 mm).

[0088] In another embodiment of this invention, the curable resin composition can be used as an adhesive for gluing or sticking parts made from the same or different substrates to form an article. The curable resin composition is first placed in contact with at least one of two or more of the same or different substrates to be joined. In one embodiment, the curable resin composition is sandwiched between the first and second substrates. The curable resin composition and the substrates are then heated at a temperature above 80°C. As a result of the heat application, an adhesive bond is formed to adhere the substrates to each other and form an article.

[0089] Although the execution and use of various embodiments of the present invention have been described in detail above, it should be understood that the present invention presents many applicable inventive concepts that can be implemented in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways of performing and using the invention, and do not set out the limits of the scope of the invention.

EXAMPLES

[0090] An exemplary resin composition was prepared using the ingredients listed as "Example 1" in Table 1. The composition was prepared by mixing DAPI, an epoxy resin (Araldite® MY 0510 available from Huntsman International LLC or an affiliate thereof), and a methyl methacrylate, butadiene, styrene ("MBS") copolymer core-shell additive powder (Clearstrength® XT 100, commercially available from Arkema) at 50°C. A polyethersulfone toughener (Virantage® VW-10200 RFP, commercially available from Solvay Specialty Polymers USA, LLC) was then added.

[0091] The composition of Example 1 was then cured for 3 hours at 160°C and further cured for 1 hour at 200°C. The cured sample was then aged at elevated temperatures in circulating air ovens at 150°C and 170°C, and then tested for Tg change by dynamic mechanical analysis (DMA) using ASTM-D4055, and for flexural strain and strength using ASTM-D790, over a period of 35 to 42 days.

[0092] Comparative Examples 1-3 (Comp. 1, Comp. 2, and Comp. 3) were prepared, cured, and evaluated in the same manner as Example 1 described above, but with different compositions, as set forth in Table 1. In particular, the composition for Comp. 1 did not have an MBS core-shell additive or a polyethersulfone toughener, the composition for Comp. 2 had an MBS core-shell additive but did not contain a polyethersulfone toughener, and Comp. 3 has a polyethersulfone toughener but does not contain an MBS core-shell additive.

[0093] The test results for Example 1 and Comparative Examples Comps. 1-3 are shown below in Tables 2-4.

Table 1

Component Comp. 1 (g) Comp. 2 (g) Comp. 3 (g) Example 1
(G) DAPI 100 100 100 100 Epoxy resin ARALDITE® MY0510 100 100 100 100 Clearstrength® XT 100 XT-100 MBS Core-Shell Supplement 10 8 Virantage® Polyethersulfone VW-10200 RFP 5 2 Total 100 110 105 110

Table 2

Tg retention (%) at 150°C Tg retention (%) at 170°C Time, day Comp.1 Comp.2 Comp.3 Example 1 Comp.1 Comp.2 Comp.3 Example 1 0 100 100 100 100 100 100 100 100 3 101.16 100 99.62 99.62 96.90 91.60 95.82 96.20 7 99.22 97.71 98.48 99.24 92.64 90.08 92.02 91.25 14 96.90 93.89 96.20 97.34 86,82 84.73 85.55 87.07 21 95.35 93.89 94.30 94.68 84.50 83.21 83.65 84.41 28 95.35 93.89 92.78 94.68 84.50 83.21 83.65 84.41 35 94.19 92.75 92.78 93.16 84.50 83.21 83.65 84.41 42 92.64 90.46 92.78 93.16 84.50 83.21 83.65 84.41

Table 3

Time, day Bending strain, %, at 170°C Bending strength, %, at 170°C Comp.1 Comp.2 Comp.3 Example 1 Comp.1 Comp.2 Comp.3 Example 1 0 5.98 5.5 5.85 7.12 19700 16700 19500 19330 7 1.50 2.31 1.64 2.87 6910 10190 7380 11460 14 1.20 1.50 1.20 1.60 6182 6804 5699 7660 21 1.10 1.30 1.10 1.60 5637 6177 5524 7130 35 1.40 1.60 1.40 1.60 5580 6210 5790 6430

[0094] The results in Tables 2 and 3 show a clear, unexpected synergistic effect when the polyethersulfone toughener is used in combination with the core-shell additive. As demonstrated by Comparative Examples 2 and 3, one of ordinary skill in the art would expect that the combination of the polyethersulfone toughener and the core-shell additive would lower the Tg value of the system having only the polyethersulfone toughener (Comp. 3). However, Example 1 shows that this combination unexpectedly exhibits a higher Tg value than Comp. 2 and Comp. 3. Equally unexpectedly improved properties are demonstrated in Table 3, which shows that the combination of the polyethersulfone toughener and the core-shell additive provides significantly increased flexural strength relative to both Comp. 2 and Comp. 3, when they were maintained as cured samples at 170°C. A person of ordinary skill in this field of technology would expect similar beneficial effects for various embodiments of the curable resin composition disclosed herein.

Claims (27)

1. A curable resin composition comprising (a) a thermosetting resin, (b) a reinforcing component comprising a multiphase polymer and a thermoplastic reinforcing agent, and (c) a phenylindanediamine curing agent, wherein the thermoplastic reinforcer is a polyethersulfone and the resin composition has a glass transition temperature of greater than 150°C upon curing. 2. The composition according to claim 1, wherein the thermosetting resin is an epoxy resin. 3. The composition according to claim 2, wherein the epoxy resin is selected from a monofunctional epoxy resin, a bifunctional epoxy resin, a trifunctional epoxy resin, a tetrafunctional epoxy resin, and a mixture thereof. 4. The composition of claim 1, wherein the composition further comprises 4,4'-methylene-bis(3-chloro-2,6-diethylaniline). 5. The composition according to claim 1, in which the phenylindanediamine hardener is a compound having the structure , wherein the amino group in the indane ring is in position 5 or 6, R ³ independently represents a hydrogen atom, a halogen atom or an alkyl group having from 1 to 6 carbon atoms, and b independently represents an integer from 1 to 4. 6. A curable resin composition comprising (a) from about 50 to about 95% by weight of a thermosetting resin, (b) from about 1 to about 15 wt.% of a reinforcing component comprising a multiphase polymer and a thermoplastic reinforcing agent, and (c) from about 5 to about 50 wt.% of a phenylindanediamine curing agent, wherein the wt.% is based on the total weight of the curable resin composition, wherein the thermoplastic reinforcer is a polyethersulfone and the resin composition has a glass transition temperature of greater than 150°C upon curing. 7. The composition of claim 6, wherein the reinforcing component comprises from about 5 to about 10 wt. % of a multiphase polymer and from about 0.1 to about 10 wt. % of a thermoplastic reinforcing agent. 8. The composition according to claim 6, wherein the phenylindanediamine hardener is a compound having the structure wherein the amino group in the indane ring is in position 5 or 6, R ³ independently represents a hydrogen atom, a halogen atom or an alkyl group having from 1 to 6 carbon atoms, and b independently represents an integer from 1 to 4. 9. A substrate at least partially coated with a curable resin composition according to claim 1. 10. The substrate according to item 9, wherein the substrate is a metal pipeline. 11. The substrate according to item 9, wherein the substrate is non-metallic. 12. The substrate according to claim 9, wherein the substrate is a steel pipe, structural steel, a storage tank, a valve or a pipeline or a casing pipe in oil or gas production. 13. A method for producing a coated substrate, comprising the steps of: (a) applying a curable resin composition according to claim 1 to the surface of the substrate; (b) heating the curable resin composition at a temperature above 80°C to cure the curable resin composition. 14. The method according to claim 13, wherein the substrate is a metal pipeline. 15. The method of claim 13, wherein the surface is the outer surface of the substrate. 16. The method of claim 13, wherein the surface is an inner surface of the substrate.