RU2646631C2 - Adhesion-improving adducts containing ligands, capable of coordinating with metal, compositions containing same and use thereof - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: group of inventions relates to adhesion-improving adducts and to compositions containing same, and used to produce sealants. Adhesion-improving adducts contain adhesion-improving groups and ligands capable of coordinating with a metal. Compositions, such as sealing compositions for the aerospace industry, contain said adhesion-improving adducts. Adhesion-improving adducts described can be used as adhesion-enhancing additives or as copolymerisable reagents in a polymer composition.

EFFECT: improved adhesion of the composition.

15 cl, 3 dwg, 9 tbl, 4 ex

Description

This application is a partial continuation of the application for US patent No. 13/529,183, filed July 21, 2012, application for US Patent No. 13 / 923,941 filed June 21, 2013, and application for US Patent No. 13 / 923,903, filed June 21, 2013, each of which fully incorporated into this text by reference.

FIELD OF THE INVENTION

The present invention relates to adhesion-improving adducts containing adhesion-improving groups and ligands capable of coordinating with a metal. Adhesion-improving adducts can be used as additives in polymer compositions, or they can be copolymerized with a sulfur-containing polymer backbone to achieve improved adhesion to metal surfaces. Also described are compositions comprising adhesion-improving adducts and sulfur-containing prepolymers that can be used to produce sealants for the aerospace field.

BACKGROUND OF THE INVENTION

Sealants that can be used in the aerospace industry and other fields of application must meet stringent mechanical, chemical, and environmental requirements. Such sealants can be applied to various surfaces, including metal surfaces, primers, intermediate coatings, topcoats and old coatings. Adhesion enhancers are typically added to sealant compositions to improve the adhesion of the various components to each other and to the surface on which the sealant is applied. There is a continuing need to develop methods for improving adhesion to the surface while maintaining other favorable sealant characteristics.

Sulfur-containing polymers such as polythioethers and polysulfides can be used in the aerospace field. Examples of suitable polythioethers and polysulfides are described, for example, in US Patent Application Publications No. 2005/0010003, 2006/0270796, 2007/0287810, 2009/0326167 and 2010/036063, each of which is incorporated herein by reference in its entirety.

Copolymerizable sulfur-containing adhesion promoters containing terminal adhesion-improving groups and used in sulfur-containing polymer compositions are described in US Patent Application No. 13 / 529,183. Sulfur-containing polymers containing bis (sulfonyl) alkanol ligands capable of coordinating with a metal included in the main chain of a sulfur-containing polymer and / or playing the role of terminal groups in a sulfur-containing polymer are described in US patent application No. 13/923,903 and US patent application No. 13 / 923,941.

SUMMARY OF THE INVENTION

Adhesion-improving adducts that can be used to enhance adhesion to metal substrates are described.

In a first aspect, adhesion improving adducts are described comprising an adhesion improving group and a ligand capable of coordinating with a metal.

In a second aspect, compositions comprising adhesion improving adducts comprising an adhesion improving group and a ligand capable of coordinating with a metal are described.

In a third aspect, cured sealants are prepared from sealant compositions containing adhesion improvers, adhesion improvers and a metal coordinating ligand.

Brief Description of the Drawings

In FIG. 1 illustrates the reaction described in example 1.

In FIG. 2 illustrates the reaction described in example 2.

FIG. 3 is a table that shows the calculated values of the energy of interaction of the ligands with the surfaces of aluminum (III) described in example 4.

The following describes private variants of the compositions and methods. The described embodiments do not limit the claims. On the contrary, the claims cover all alternatives, modifications and equivalents of the invention.

Detailed description

Definitions

In the context of the present description, it should be understood that the embodiments described herein allow for various alternatives and stages, unless explicitly stated otherwise. In addition, with the exception of examples or cases where otherwise is specifically indicated, all figures reflecting, for example, the amounts of ingredients used in the description and claims, should be understood as preceded by the term "about". Accordingly, unless otherwise indicated, the numerical parameters given in the present description and claims are approximate values, which may vary depending on the target characteristics that need to be achieved. Finally, but not as a limitation of the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be interpreted at least in light of the number of significant digits given and using standard rounding techniques.

Although the numerical ranges and parameters describing the wide scope of the present invention are approximate values, the numerical values given in the specific examples are given as accurately as possible. However, any numerical value by its nature contains certain errors, which are the inevitable result of standard deviations in the corresponding test measurements.

It should also be understood that any numerical interval given in this text includes all sub-intervals included in it. For example, the interval “from 1 to 10” includes all sub-intervals between (and inclusive) a reduced lower value of about 1 and a maximum value of about 10, that is, having a minimum value of about 1 or more, and a maximum value equal to about 10 or less. Also in this text, the use of the term “or” means “and / or” unless expressly indicated otherwise, even though in some cases “and / or” may be used explicitly.

A dash ("-"), not located between two letters or symbols, is used to indicate the point of attachment of a substituent or binding between atoms. For example, —CONH ₂ is linked to another fragment via a carbon atom.

The term "alkanediyl" refers to the diradical of a saturated branched or linear acyclic hydrocarbon group containing, for example, from 1 to 18 carbon atoms (C _1-18 ), from 1 to 14 carbon atoms (C _1-14 ), from 1 to 6 atoms carbon (C _1-6 ), from 1 to 4 carbon atoms (C _1-4 ) or from 1 to 3 carbon atoms (C _1-3 ). Branched alkanediyl contains at least three carbon atoms. In certain embodiments, the alkanediyl is C _2-14 alkanediyl, C _2-10 alkanediyl, C _2-8 alkanediyl, C _2-6 alkanediyl, C _2-4 alkanediyl,, in certain embodiments, C _2-3 alkanediyl. Examples of alkanediyl groups include methane-diyl (-CH ₂ -), ethane-1,2 diyl (-CH ₂ CH ₂ -), propan-1,3-diyl and iso-propan-1,2-diyl (e.g., - CH ₂ CH ₂ CH ₂ - and -CH (CH ₃ ) CH ₂ -), butane-1,4-diyl (-CH ₂ CH ₂ CH ₂ CH ₂ -), pentane-1,5-diyl (-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -), hexane-1,6-diyl (-CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ -), heptane-1,7-diyl, octane-1,8-diyl , nonane-1,9-diyl, decane-1,10-diyl, dodecane-1,12-diyl and the like.

The term "alkanocycloalkane" refers to a saturated hydrocarbon group containing one or more cycloalkyl and / or cycloalkanediyl groups and one or more alkyl and / or alkanediyl groups, where cycloalkyl, cycloalkanediyl, alkyl and alkanediyl meet the definitions given in this text. In certain embodiments, each cycloalkyl and / or cycloalkanediyl group (s) is C _3-6 , C _5-6, and, in certain embodiments, cyclohexyl or cyclohexanediyl. In certain embodiments, each alkyl and / or alkanediyl group (s) is C _1-6 , C _1-4 , C _1-3, and, in certain embodiments, methyl, methanediyl, ethyl or ethane-1,2-diyl . In certain embodiments, the alkanecycloalkane group is C _4-18 alkanecycloalkane, C _4-16 alkanecycloalkane, C _4-12 alkanecycloalkane, C _4-8 alkanecycloalkane, C _6-12 alkanecycloalkane, C _6-10 alkanecycloalkane, and, in certain embodiments, C _6-9 alkanocycloalkane. Examples of alkanecycloalkane groups include 1,1,3,3-tetramethylcyclohexane and cyclohexylmethane.

The term "alkanecycloalkanediyl" refers to a diradical of an alkanecycloalkane group. In certain embodiments alkantsikloalkandiilnaya group is a C _4-18 alkantsikloalkandiil, C _4-16 alkantsikloalkandiil, alkantsikloalkandiil C _4-12, C _4-8 alkantsikloalkandiil, alkantsikloalkandiil C _6-12, C _6-10 alkantsikloalkandiil, and in certain embodiments, C _6-9 alkanocycloalkanediyl. Examples of alkanecycloalkanediyl groups include 1,1,3,3-tetramethylcyclohexane-1,5-diyl and cyclohexylmethane-4,4'-diyl.

The term "alkenyl" group refers to the group (R) ₂ C = C (R) ₂ or -RC = C (R) ₂ , where the alkenyl group is terminal and is attached to a larger molecule. In such embodiments, each R may be selected, for example, from a hydrogen atom and C _1-3 alkyl. In some embodiments, each R represents a hydrogen atom, and the alkenyl group has the structure —CH═CH ₂ .

The term “alkoxy” refers to an —OR group, where R is alkyl, as defined herein. Examples of alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy and n-butoxy. In certain embodiments, an alkoxy group is a C _1-8 alkoxy, C _1-6 alkoxy, C _1-4 alkoxy, and, in certain embodiments, a C _1-3 alkoxy group.

The term “alkyl” refers to a mono radical of a saturated, branched or linear acyclic hydrocarbon group containing, for example, from 1 to 20 carbon atoms, from 1 to 10 carbon atoms, from 1 to 6 carbon atoms, from 1 to 4 carbon atoms, or from 1 up to 3 carbon atoms. In some embodiments, the alkyl group is C _2-6 alkyl, C _2-4 alkyl, and, in some embodiments, C _2-3 alkyl. Examples of alkyl groups include methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-hexyl, n-decyl, tetradecyl and the like. In certain embodiments, the alkyl group is C _2-6 alkyl, C _2-4 alkyl, and, in certain embodiments, C _2-3 alkyl. A branched alkyl group contains at least three carbon atoms.

The term "cycloalkanediyl" refers to a diradical of a saturated monocyclic or polycyclic hydrocarbon group. In certain embodiments, the cycloalkanediyl group is C _3-12 cycloalkanediyl, C _3-8 cycloalkanediyl, C _3-6 cycloalkanediyl, and, in certain embodiments, C _5-6 cycloalkanediyl. Examples of cycloalkanediyl groups include cyclohexane-1,4-diyl, cyclohexane-1,3-diyl and cyclohexane-1,2-diyl.

The term “cycloalkyl” refers to a saturated monocyclic or polycyclic hydrocarbon monoradical group. In certain embodiments, the cycloalkyl group is C _3-12 cycloalkyl, C _3-8 cycloalkyl, C _3-6 cycloalkyl, and, in certain embodiments, C _5-6 cycloalkyl.

The term "bis (sulfonyl) alkanol group" refers to a group having the general Formula (1):

where each R ^{10 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituent groups are —OH. In some embodiments, the bis (sulfonyl) alkanol group has the structure —CH ₂ —CH ₂ —S (O) ₂ —R ¹⁰ —CH (—OH) —R ¹⁰ —S (O) ₂ —CH ₂ —CH ₂ -, and, in some embodiments, the implementation of the structure —R ⁹ —S (O) ₂ —R ¹⁰ —CH (—OH) —R ¹⁰ —S (O) ₂ —R ⁹ -, wherein each R ⁹ is an organic moiety; and each R ^{10 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituent groups are —OH.

In some embodiments, the “bis (sulfonyl) alkanol group” may be a monovalent bis (sulfonyl) alkanol group or a divalent bis (sulfonyl) alkanol group. In some embodiments, the monovalent bis (sulfonyl) alkanol may be a terminal bis (sulfonyl) alkanol group, such as a "1- (ethylene sulfonyl) n- (vinyl sulfonyl) alkanol group." The terminal bis (sulfonyl) alkanol group can be obtained by the reaction of bis (sulfonyl) alkanol and may have a terminal fragment with the general structure —R ⁹ —S (O) ₂ —R ¹⁰ —CH (—OH) —R ¹⁰ —S (O) ₂ -R ⁸ , where R ⁹ is a fragment formed by the reaction of bis (sulfonyl) alkanol with a compound having a group capable of reacting with bis (sulfonyl) alkanol; each R ^{10 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituent groups are —OH. In some embodiments, R ⁸ is —CH═CH ₂ . In some embodiments, the terminal bis (sulfonyl) alkanol group is a 1- (ethylene sulfonyl) n- (vinylsulfonyl) alkanol group, such as 1- (ethylene sulfonyl) -3- (vinylsulfonyl) propan-2-ol, i.e. -CH ₂ -CH ₂ -S (O) ₂ -CH ₂ -CH (-OH) -CH ₂ -S (O) ₂ -CH = CH ₂ . In some embodiments, the terminal bis (sulfonyl) alkanol group has the structure —CH ₂ —CH ₂ —S (O) ₂ —R ¹⁵ —CH (—OH) —R ¹⁵ —S (O) ₂ —CH = CH ₂ .

In some embodiments, the bis (sulfonyl) alkanol group may also be divalent, as in the case where this group is included in the main chain of a prepolymer, such as the polythioesters described in US patent application No. 13/923,903. In some embodiments, the divalent bis (sulfonyl) alkanol group may have the general structure —R ⁹ —S (O) ₂ —R ¹⁵ —CH (—OH) —R ¹⁵ —S (O) ₂ —R ⁹ -; in some embodiments, —CH ₂ —CH ₂ —S (O) ₂ —R ¹⁵ —CH (—OH) —R ¹⁵ —S (O) ₂ —CH ₂ —CH ₂ -; in some embodiments, —R ⁹ - S (O) ₂ —CH ₂ —CH (—OH) —CH ₂ —S (O) ₂ —R ⁹ -, and in some embodiments, —CH ₂ —CH ₂ —S (O) ₂ —CH ₂ —CH (—OH) —CH ₂ —S (O) ₂ —CH ₂ —CH ₂ -, wherein R ⁹ and R ¹⁵ are as defined herein. In some embodiments, bis (sulfonyl) alkanol each R ⁹ represents an ethanediyl group and / or each R ¹⁵ represents methanediyl.

The term “bis (sulfonyl) alkanol” refers to a compound of the general formula R ⁸ —S (O) ₂ —R ¹⁵ —CH (—OH) —R ¹⁵ —S (O) ₂ —R ⁸ , wherein each R ⁸ is a moiety containing a terminal reactive group; and each R ^{10 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituent groups are —OH. In some embodiments, each R ⁸ contains a terminal group capable of reacting with a thiol group, such as, for example, an alkenyl group, an epoxy group, a Michael acceptor group or a saturated carbon atom group carrying a leaving group well suited for nucleophilic substitution such as, for example, —Cl, —Br, —I, —OSO ₂ CH ₃ (mesylate), —OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate), etc. In some embodiments, the bis (sulfonyl) alkanol may be a bis (vinylsulfonyl) alkanol containing terminal alkenyl groups. In some embodiments, the bis (sulfonyl) alkanol may be a bis (vinylsulfonyl) alkanol in which R ⁸ contains a terminal alkenyl group, such as a compound having the formula CH ₂ = CH-S (O) ₂ —R ¹⁵ —CH (- OH) -R ¹⁵ -S (O) ₂ -CH = CH ₂ . In some embodiments, the bis (vinylsulfonyl) alkanol is 1,3-bis (vinylsulfonyl) -2-propanol. In some embodiments, a compound containing bis (sulfonyl) alkanol can be prepared by reacting a bis (vinylsulfonyl) alkanol with a compound containing a reactive terminal functional group and a terminal group capable of reacting with terminal alkenyl groups of a bis (vinylsulfonyl) alkanol, such as a thiol group or epoxy group. In such embodiments, the bis (sulfonyl) alkanol may have the structure R ⁹ —CH ₂ —CH ₂ —S (O) ₂ —R ¹⁵ —CH (—OH) —R ¹⁵ —S (O) ₂ —CH ₂ —CH ₂ -R ⁹ , where each R ⁹ is a fragment formed by the reaction of this compound with terminal alkenyl groups of bis (vinylsulfonyl) alkanol.

"Bis (sulfonyl) alkanol-containing" polymer, prepolymer or adduct means a polymer, prepolymer or adduct in which one or more divalent bis (sulfonyl) alkanol groups are included in the backbone of the polymer, prepolymer or adduct.

The divalent bis (sulfonyl) alkanol group can be included in the prepolymer by reaction, for example, in a suitable ratio, of a polythiol monomer or prepolymer of Formula (2) with a bis (sulfonyl) alkanol of Formula (3):

where R is an organic fragment, w is an integer of at least 2, and each R ⁸ contains a terminal group capable of reacting with a thiol group, such as, for example, an alkenyl group and an epoxy group, or a group containing a saturated carbon atom, bearing a leaving group well suited for nucleophilic substitution, such as, for example, —Cl, —Br, —I, —OSO ₂ CH ₃ (mesylate), —OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate), etc. d. In some embodiments, a bis (sulfonyl) alkanol of Formula (3) may be a bis (vinylsulfonyl) alkanol having the structure of Formula (4):

where each R ^{10 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituent groups are —OH. In some embodiments, the bis (sulfonyl) alkanol may be 1,3-bis (vinylsulfonyl) -2-propanol. Alternatively, the bis (sulfonyl) alkanol group can be introduced into the main chain of the prepolymer by reaction, in an appropriate ratio, of the thiol-terminal bis (sulfonyl) alkanol of Formula (5) with a reagent of Formula (6):

where each R ²⁰ represents a divalent moiety, each R ¹⁰ corresponds to the definition given in this text, and each R ²¹ contains a terminal group capable of reacting with a thiol group, such as, for example, an alkenyl group, an epoxy group or a group consisting of saturated a carbon atom carrying a leaving group well suited for nucleophilic substitution, such as, for example, —Cl, —Br, —I, —OSO ₂ CH ₃ (mesylate), —OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate) etc.

By selecting the desired ratio of the reagents of Formula (2) and Formula (3), or Formula (5) and Formula (6), one or more bis (sulfonyl) alkanol groups can be introduced into the prepolymer as a chain segment, as a terminal reactive group, or both options are used. For example, bis (vinylsulfonyl) alkanol can be used to introduce one or more 1, n-bis (ethylenesulfonyl) alkanol groups into the main chain of the prepolymer chain, one or more terminal 1- (ethylenesulfonyl) -n- (vinylsulfonyl) alkanol groups, or use both of these options.

In some embodiments, bis (vinylsulfonyl) -2-propanol can be reacted with thiol terminal monomers / polymers to introduce 1,3-bis (ethylene sulfonyl) -2-propanol groups into the polymer chain.

In some embodiments, bis (vinylsulfonyl) -2-propanol can be reacted with thiol terminal monomers / polymers to produce 1- (ethylene sulfonyl) -3- (vinylsulfonyl) -2-propanol terminal groups, wherein the terminal alkenyl group is well famous Michael acceptor.

The fragment formed by the reaction of a bis (sulfonyl) alkanol with a thiol group is the reaction product of a thiol group and a fragment containing a terminal group capable of reacting with a thiol group. Examples of terminal groups capable of reacting with thiol groups include epoxy groups, alkenyl groups, Michael acceptor groups and groups containing a saturated carbon atom bearing a leaving group well suited for nucleophilic substitution, such as, for example, -Cl, -Br , -I, -OSO ₂ CH ₃ (mesylate), -OSO ₂ -C ₆ H ₄ -CH ₃ (tosylate), etc. In some embodiments, the fragment formed by the reaction of a bis (sulfonyl) alkanol with a thiol group has the structure: —CH ₂ —CH ₂ —R—, —GH (—OH) —CH ₂ —R—, —CH ₂ —CH ( —OH) —R— or —CH ₂ —CH ₂ —SO ₂ —R—, where R is a covalent bond or organic moiety bound to a sulfonyl group.

The fragment formed by the reaction of a bis (sulfonyl) alkanol with a thiol group is denoted in the same way as the fragment R ⁹ which is formed by the reaction of the group R ⁸ with a thiol group, where R ⁸ is a terminal group capable of reacting with a thiol group.

In some embodiments, R ⁹ is formed during the reaction of a bis (sulfonyl) alkanol with a compound having a terminal group capable of reacting with a thiol group and a group capable of reacting with a bis (sulfonyl) alkanol. In some embodiments, R ⁹ is formed during the reaction of a bis (vinylsulfonyl) alkanol with a compound having a terminal group capable of reacting with a thiol group and a group capable of reacting with an alkenyl group. In such an embodiment, R ⁹ may have the structure: —CH ₂ —CH ₂ —R′ — CH ₂ —CH ₂ -, —CH (—OH) —CH ₂ —R′ — CH ₂ —CH ₂ -, —CH ₂ -CH (-OH) -R'-CH ₂ -CH ₂ - or -CH ₂ -CH ₂ -SO ₂ -R'-CH ₂ -CH ₂ -, where R 'is an organic fragment obtained by the reaction of a compound used for introducing into the bis (ethylene sulfonyl) alkanol a terminal functional group such as an alkenyl group, an epoxy group, a Michael acceptor group or a saturated carbon atom group carrying a leaving group well suited for nucleophilic substitution, such as, for example, -Cl , -Br, -I, -OSO ₂ CH ₃ (mesylate), -OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate), etc.

In some embodiments, R ^{9 is} selected from C _2-10 alkanediyl, substituted C _2-10 alkanediyl, C _2-10 heteroalkanediyl, substituted C _2-10 heteroalkanediyl, C _4-14 alkanocycloalkanediyl, substituted C _4-14 alkanocycloalkanediyl, C _{4- 14} heteroalkanecycloalkanediyl, substituted C _4-14 heteroalkanecycloalkanediyl, C _4-14 alkanarendiyl, substituted C _4-14 alkanarendiyl, C _4-14 heteroalkanediandyl and substituted C _4-14 heteroalkanediandyl. In some embodiments, R ⁹ is ethanediyl.

In some embodiments, R ^{9 is} selected from C _2-10 alkyl, substituted C _2-10 alkyl, C _2-10 heteroalkyl, substituted C _2-10 heteroalkyl, C _4-14 alkanocycloalkyl, substituted C _4-14 alkanocycloalkyl, C _{4- 14} heteroalkanecycloalkyl, substituted C _4-14 heteroalkanecycloalkyl, C _4-14 alkanaryl, substituted C _4-14 alkanaryl, C _4-14 heteroalkanaryl and substituted C _4-14 heteroalkanaryl. In some embodiments, R ⁸ is ethylene, i.e. -CH = CH ₂ .

"Acetylacetonate group" means a group having the structure of Formula (1):

In some embodiments, the implementation of acetylacetonate means a metal chelating agent containing an acetylacetonate group and one or more reactive functional groups.

The term “hydroxypyridinone groups” includes groups such as 3-hydroxy-4-pyridinone and 3-hydroxy-2-pyridinone having the structure of Formula (8a) or Formula (8b), respectively:

where R represents an organic group, such as an alkyl group. The hydroxypyridinone metal chelating agent contains a hydroxypyridinone group and one or more reactive functional groups, such as terminal thiol groups.

The term "quinones" means compounds having a fully conjugated cyclic dione structure obtained from aromatic compounds by converting an even number of -CH = groups to -C = O) - groups, with the necessary rearrangement of double bonds. Examples of quinones include 1,2-benzoquinone, 1,4-benzoquinone, 1,4-naphthaloquinone and 9,10-anthraquinone. Quinone groups can be ligands capable of coordinating with a metal.

The term “ligand capable of coordinating with a metal” refers to an ion or molecule that binds to a metal atom and, potentially, to other atoms to form a coordination complex. The bonding between the metal and / or atoms usually involves donating one or more pairs of electrons to the metal, and the nature of such bonding may consist, for example, in a covalent, ionic or hydrogen bond. Ligands capable of coordinating with the metal described herein are capable of forming coordination complexes with surfaces used in the aerospace field, such as aluminum and titanium surfaces, which can be oxidized. In the case of oxidized surfaces, a ligand capable of coordinating with a metal can form a coordination complex with a metal such as Al (III) and oxygen atoms. The coordination complex can increase adhesion to the surface of a metal or oxidized metal.

Ligands capable of coordinating with the metal can be incorporated into the prepolymer backbone as described herein. In addition to a fragment capable of forming a coordination complex, for incorporation into the main chain of a prepolymer, a ligand capable of coordinating with a metal is included or modified in order to include at least two groups capable of reacting with a group of a sub-fragment of the prepolymer. Such reactive ligands capable of coordinating with the metal may be commercially available or may be derivatized to include suitable reactive substituent groups using methods known to those skilled in the art.

The term “heteroalkanediyl” refers to an alkanediyl group in which one or more carbon atoms is replaced by a heteroatom, such as N, O, S or P. In some embodiments, the heteroalkanediyl heteroatom is selected from N and O.

The term “heterocycloalkanediyl” refers to a cycloalkanediyl group in which one or more carbon atoms is replaced by a heteroatom such as N, O, S, or P. In some embodiments, the heterocycloalkanediyl heteroatom is selected from N and O.

The term "Michael acceptor" refers to an activated alkene, such as an alkenyl group adjacent to an electron-acceptor group, such as a keto, nitro, halogen, nitrile, carbonyl or nitro group. Michael acceptors are well known in the art. The term “Michael acceptor group” means an activated alkenyl group and an electron acceptor group. In some embodiments, the Michael acceptor group is selected from vinyl ketone, vinyl sulfone, quinone, enamine, ketimine, aldimine, oxazolidine and acrylate. Other examples of Michael acceptors are described in Mather et al., Prog. Polym. ScL, 2006, 31, 487-531 and include acrylate esters, acrylonitrile, acrylamides, maleimides, alkyl methacrylates, cyanoacrylates. Other Michael acceptors include vinyl ketones, α, β-unsaturated aldehydes, vinyl phosphonates, acrylonitrile, vinyl pyridines, some azo compounds, β-keto-acetylenes and acetylene esters. In some embodiments, the Michael acceptor group is a vinyl ketone derivative and has the structure of the formula —S (O) ₂ —C (R) ₂ = CH ₂ , where each R is independently selected from a hydrogen atom, fluorine, and C _1-3 alkyl. In some embodiments, each R represents a hydrogen atom. In some embodiments, the Michael acceptor or Michael acceptor group does not encompass acrylates. The term “Michael acceptor compound” means a compound containing at least one Michael acceptor. In some embodiments, the Michael acceptor compound is divinyl sulfone, and the Michael acceptor group is vinyl sulfonyl, for example —S (O) ₂ —CH ₂ = CH ₂ .

The term “Michael acceptor” refers to substituted alkene / alkyne compounds in which at least one alkene / alkyne group is directly attached to one or more electron-acceptor groups, such as carbonyl (—CO), nitro group (—NO ₂ ) , nitrile (-CN), alkoxycarbonyl (-COOR), phosphonate (-PO (OR) ₂ ), trifluoromethyl (-CF ₃ ), sulfonyl (-SO ₂ -), trifluoromethanesulfonyl (-SO ₂ CF ₃ ), p-toluenesulfonyl (-SO ₂ -C ₆ C ₄ -CH ₃ ), etc. Types of compounds that act as Michael acceptors are vinyl ketones, quinones, nitroalkenes, acrylonitriles, acrylates, methacrylates, cyanoacrylates, acrylamides, maleimides, dialkyl vinylphosphonate and vinyl sulfones. Other examples of Michael acceptors are described in Mather et al, Prog. Polym. Sci. 2006, 31, 487-531. Michael acceptor compounds having more than one Michael acceptor group are also well known. Examples include diacrylates such as ethylene glycol diacrylate and diethylene glycol diacrylate, dimethacrylates such as ethylene glycol methacrylate and diethylene glycol methacrylate, bismaleimides such as N, N '- (1,3-phenylene) dimaleimide and 1,1' - (methylenedi-4, 1-phenylene) bismaleimide, vinyl sulfones such as divinyl sulfone and 1,3-bis (vinyl sulfonyl) -2-propanol, etc. In some embodiments, the Michael acceptor group has the structure of Formula (9a) or Formula (9b):

where each R ^{15 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituent groups are —OH.

The term “Michael acceptor compound” refers to a compound containing at least one Michael terminal acceptor group. In some embodiments, the Michael acceptor compound is divinyl sulfone, and the Michael acceptor group is vinyl sulfonyl, i.e. -S (O) ₂ -CH = CH ₂ . In some embodiments, the Michael acceptor compound is bis (vinylsulfonyl) alkanol, and the Michael acceptor group is 1- (ethylene sulfonyl) n- (vinylsulfonyl) alkanol, i.e. —CH ₂ —CH ₂ —S (O) ₂ —R ¹⁰ —CH (—OH) —R ¹⁰ —S (O) ₂ —CH = CH ₂ , and, in some embodiments, 1- (ethylene sulfonyl) -3 - (vinylsulfonyl) propan-2-ol (-CH ₂ -CH ₂ -S (O) ₂ -CH ₂ -CH (-OH) -CH ₂ -S (O) ₂ -CH = CH ₂ ).

The term "polyalkoxysilyl group" refers to a group having the structure of Formula (10):

where p is selected from 0, 1 and 2; and each R ^{7 is} independently selected from C _1-4 alkyl. In some embodiments of the polyalkoxysilyl group, p is 0, p is 1, and in some embodiments, p is 2. In some embodiments of the polyalkoxysilyl group, each R ^{7 is} independently selected from ethyl and methyl. In some embodiments of the polyalkoxysilyl group, each R is ethyl, and in some embodiments, each R ⁷ is methyl. In some embodiments of the polyalkoxysilyl group, this group is selected from —Si (—OCH ₂ CH ₃ ) ₃ , —Si (—OCH ₃ ) ₃ , —Si (—CH ₃ ) (—CH ₃ ) ₂ , —Si (—CH ₃ ) ₂ (-OCH ₃ ), -Si (-CH ₃ ) (- OCH ₂ CH ₃ ) ₂ , -Si (-CH ₃ ) ₂ (-OCH ₂ CH ₃ ), -Si (-CH ₂ CH ₃ ) (- OCH ₃ ) and -Si (-CH ₂ CH ₃ ) ₂ (-OCH ₃ ).

The term "polyalkoxysilane" refers to a compound containing a polyalkoxysilane group. Polyalkoxysilyl groups are adhesion-improving groups, and therefore polyalkoxysilanes are adhesion promoters.

In some embodiments, the polyalkoxysilane has the formula R ¹¹ -PR ¹² , where P is a polyalkoxysilane core, R ¹¹ contains a polyalkoxysilyl group, and R ¹² contains a reactive functional group.

As used herein, the term “polymer” refers to oligomers, homopolymers and copolymers. Unless otherwise indicated, molecular weights are number average molecular weights for polymeric materials, are designated “Mn”, and are determined, for example, by gel permeation chromatography using polystyrene standards by known methods. The term "prepolymer" is also used to refer to the polymer components of a composition that, after curing, form a cured polymer.

The term “substituted” refers to a group in which one or more hydrogen atoms are each independently replaced with the same or different substituents. In certain embodiments, a substituent is selected from halogen, —S (O) ₂ OH, —S (O) ₂ , —SH, —SR, where R is C _1-6 alkyl, —COOH, —NO ₂ , —NR ₂ where each R is independently selected from a hydrogen atom and C _1-3 alkyl, —CN, ═O, C _1-6 alkyl, C _1-3 alkyl, —CF ₃ , —OH, phenyl, C _2-6 heteroalkyl, C _5-6 heteroaryl, C _1-6 alkoxy groups and —COR, where R is C _1-6 alkyl. In certain embodiments, a substituent is selected from —OH, —NH _2, and C _1-3 kilograms.

Particular embodiments of adhesion improving adducts, prepolymers, compositions and methods are described below. The described embodiments do not limit the scope of the claims. On the contrary, the claims cover all alternatives, modifications and equivalents.

Adhesion Improving Adducts

The adhesion improving adducts described herein include an adhesion improving group and a ligand capable of coordinating with the metal.

Groups promoting adhesion to metal surfaces are well known in the prior art. Examples of groups promoting adhesion to metal surfaces include polyalkoxysilyl groups, phosphonate groups, amine groups, including primary and secondary amines, carboxyl groups and phosphonic acid groups.

In some embodiments, the adhesion improving group may be a polyalkoxysilyl group, which may have the structure —Si (R ⁴ ) _y1 (OR ⁵ ) _y2 , where y1 is selected from 0, 1, and 2; y2 is selected from 1, 2, and 3; and the sum of y1 and y2 is 3; each R ^{4 is} independently selected from C _1-4 alkyl; and each R ⁵ independently represents C _1-4 alkyl.

In some embodiments, the adhesion improving group may be a phosphonate group, which may have the structure —P (═O) (OR ⁶ ) ₂ , where each R ^{6 is} independently selected from C _1-4 alkyl. In some embodiments, the adhesion improver may be a phosphonic acid group that has the structure —P (═O) (OR ⁶ ) ₂ , where each R ⁶ represents a hydrogen atom.

In some embodiments, the adhesion improving group may be a primary amine, and, in some embodiments, a secondary amine.

In some embodiments, the adhesion improver may be a carboxy group.

Typical aerospace ship surfaces include, for example, aluminum, anodized aluminum, Al (III), Alodine®, and titanium. Thus, for use in aerospace sealants, it is desirable that the metal chelating agent coordinate with aluminum, alumina, Alodine®, titanium and titanium oxide. Thus, in some embodiments, a ligand capable of coordinating with a metal comprises a moiety capable of forming a coordination complex with one or more of the listed surfaces used in the aerospace industry. In addition to the formation of the coordination complex with the metal, other transition metals or elements, such as oxygen, can participate in the formation of the coordination complex through covalent, ionic interaction or hydrogen bonds. For use on other surfaces, a suitable ligand capable of coordinating with the metal can be selected.

Ligands capable of coordinating with a metal, and in particular ligands capable of coordinating with a metal, for aluminum (III) include Lewis hard bases such as —OH, —PO ₄ , —SO ₄ , —COOH, —C = O and —NH ₂ groups that are capable of coordinating with a metal or an oxidized metal such as aluminum (III). The main donor groups that efficiently form multidentate coordination complexes with aluminum (III) include anions of aliphatic monohydroxy acids, catecholates, anions of aromatic hydroxy acids, 3-hydroxy-4-pyridinones, hydroxamates and 3-hydroxy-2-pyridinones. Complexes of aluminum (III) with multidentate ligands having negatively charged oxygen electron donors are stable. A ligand capable of coordinating with the metal can form a multidentate complex with the metal, such as a bidentate complex or a tridentate complex.

In some embodiments, the functional group of the ligand capable of coordinating with the metal is a derivative of a metal chelating agent selected from bis (sulfonyl) alkanol, benzoquinone, hydroxypyridinone and acetylacetonate.

Examples of ligands for aluminum, aluminum oxide and / or Al (III) include 2,3-dihydroxybenzoic acid, 5-nitrosalicylate, 3-hydroxy-4-pyridinone, 3-hydroxy-2-pyridinone, 2-2'-dihydroxyazobenzene, 8 -hydroxyquinoline, oxalate, malonate, citrate, iminodiacetic acid, picolinic acid, maltol, kojic acid, N, N'-diacetic acid (EDTA), N- (2-hydroxy) ethylenediamine triacetic acid (HEDTA), ethylenediamine-N bis (2-hydroxyphenylacetic acid (EDDHA) and N, N'-bis (hydroxybenzyl) ethylenediamine-N, N'-diacetic acid (HBED), acetoacetate and quinone. Other chelators for a Yuminov and alumina are described in, for example, in Yokel, Coordination Chemistry Reviews 2002, 228, 97-113; and Martell et al, Coordination Chemistry Reviews 1996, 149, 311-328..

Examples of ligands for titanium or titanium oxide include H ₂ O ₂ , acetoacetonate (CH ₂ (COCH ₃ ) ₂ ), EDTA, trans-1,2-cyclohexanediamine tetraacetic acid, glycol ether diamine tetraacetic acid (GEDTA, (CH ₂ OCH ₂ CH ₂ N ₂ (CH ₂ COOH) ₂ ) ₂ ), diethylenetriamine pentaacetic acid (DTPA, HOOCH ₂ N (CH ₂ CH ₂ N (CH ₂ COOH) ₂ ) ₂ ), nitrile triacetic acid (NTA, N (CH ₂ COOH) ₃ ), salicylic acid, lactic acid, acetylacetonate, triethanolamine, and a combination of any of the above.

In some embodiments, a ligand capable of coordinating with a metal contains at least two heteroatom groups capable of coordinating with aluminum (III). In some embodiments, the ligand capable of coordinating with the metal contains at least two heteroatom groups selected from —OH, —PO ₄ , —P (O) ₂ - —SO ₄ , —S (O) ₂ -, —COOH, -C = O, -NH ₂ , -NH- and combinations of any of the above.

In US Patent Applications 13 / 923,903 and 13 / 923,941, Cai et al. describe bis (sulfonyl) alkanol groups in combination with sulfur-containing polymers to enhance the surface adhesion of hardened compositions to surfaces used in the aerospace industry. Bis (sulfonyl) alkanol groups may have the structure of Formula (11a) or Formula (11b):

wherein each R ^{15 is} independently selected from C _1-3 alkanediyl and substituted C _1-3 alkanediyl, where one or more substituents are —OH.

In some embodiments, a metal-coordinated ligand comprises a structure of Formula (12a), Formula (12b), Formula (12c), Formula (12d), Formula (12e), and a combination of any of the following:

where each X is independently selected from —C (O) - and —S (O) ₂ -; n is an integer from 1 to 3; and R ⁵ represents C _1-4 alkanediyl.

In some embodiments, the metal coordinated ligand comprises bis (sulfonyl) alkanol, hydroxypyridinone, quinone, acetylacetonate, or a combination of any of the above.

The adhesion improving adducts described herein may also contain a reactive group that reacts with a polyfunctionalizing agent or with a prepolymer functional group. For example, a reactive group can be reacted with a terminal group of a polyfunctionalizing agent and used to produce a polyvalent adhesion-improving adduct, copolymerizable adhesion-improving adduct, or copolymerizable sulfur-containing adhesion-improving adduct, as described herein. In other embodiments, the reactive group may react with a functional group of a multifunctional sulfur-containing prepolymer, such as a polythioether or polysulfide, and / or may react with a hardener. In any case, the reactive group can be used to graft the adhesion-improving adduct to the backbone of the hardened polymer, which can be used to increase the adhesion force of the composition.

In some embodiments, the adhesion improver adduct comprises a reaction product of reagents comprising an adhesion promoter containing an adhesion improver group and a functional group, and a metal chelating agent containing a ligand capable of coordinating with the metal, and a functional group capable of reacting with the functional group of the adhesion promoter. For example, in some embodiments, the adhesion improver adduct comprises a reaction product of reagents comprising an adhesion promoter of Formula R ¹¹ -PR ¹² and a metal chelating agent of Formula R ¹³ -MR ¹⁴ , where R ¹¹ is an adhesion improver, P is a core of an adhesion promoter , M represents a ligand capable of coordinating with the metal, R ¹² and R ¹³ include mutually reactive functional groups, and R ^{14 is} selected from a non-reactive group, a reactive functional group or is absent.

In some embodiments, the adhesion improving adduct has the structure of Formula (13):

where R ¹¹ contains an adhesion improving group;

P contains a core adhesion promoter;

M contains a ligand capable of coordinating with the metal;

R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ -PR ¹² and the metal chelating agent R ¹³ -MR ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ selected from a non-reactive group, a reactive functional group or absent.

Suitable reaction conditions for the interaction of the adhesion promoter and a metal chelating agent to produce an adhesion-improving adduct can be determined by a person skilled in the art.

In some embodiments, the adhesion promoter comprises an alkenyl group, a thiol group, or an amino group that can react with a metal chelating agent group. In some embodiments, the adhesion promoter is a thiol-terminal polyalkoxysilane.

In some embodiments, the adhesion promoter comprises mercaptosilane, and, in some embodiments, aminosilane. Examples of polyalkoxysilyl-containing adhesion promoters containing a reactive amino or thiol group include amine-functional adhesion promoters such as N- (β-aminoethyl) γ-aminopropyltrimethoxysilane (Silquest® A-1120) and thiol-functional adhesion promoters, such as γ-mercaptopropyltrimethoxysilane (Silquest® A-189).

In some embodiments, the adhesion promoter has a structure of Formula (14a), a structure of Formula (14b), a structure of Formula (14c), or a combination of any of the following:

)

)

where each R ^{16 is} independently selected from C _1-3 alkyl, and each R ^{17 is} selected from a hydrogen atom and C _1-3 alkyl.

In some embodiments, the metal chelating agent is a chelating agent for aluminum or alumina and is selected from bis (sulfonyl) alkanol, quinone, acetylacetonate, hydroxypyridinone, and a combination of any of the above. In particular, examples of chelating agents for aluminum include acetylacetonates, such as 2- (methylacryloyloxy) ethyl acetoacetate (2-MEAA), hydroxypyridinones, such as 3-hydroxy-4-pyridinone and 3-hydroxy-2-pyridinone, and bis (sulfonyl ) alkanols such as bis (vinylsulfonyl) -2-propanol.

In some embodiments, a thiol terminal adhesion promoter, such as γ-mercaptopropyltrimethoxysilane, can be reacted with bis (sulfonyl) alkanol, such as 1,3-bis (vinylsulfonyl) -2-propanol, to obtain an adhesion-improving adduct of Formula (15) :

.

.

where each R ^{16 is} independently selected from methyl and ethyl.

As another example, an amine-functional adhesion-improving adduct, such as N- (β-aminoethyl) γ-aminopropyltrimethoxy silane, can be reacted with an acrylate or benzoquinone-containing metal chelating agent such as 2- (methacryloyloxy) ethyl acetoacetate (2-MEAA) or benzoquinone (it is impossible to directly depict this structure), obtaining adhesion-improving adducts having structures of Formulas (16a) - (16d):

where each R ^{16 is} independently selected from methyl and ethyl.

As can be understood from the above examples, the mutually reactive functional groups of the adhesion promoter and metal-chelating agent can be terminal functional groups or can be part of the core of the adhesion promoter or metal-chelating agent. So, in some embodiments, the implementation of the fragments -P- and -M- may contain one or more reactive functional groups.

Long Adhesion Improving Adducts

In some embodiments, the adhesion improving adduct comprises one or more reactive functional groups. These reactive functional groups can be reacted with another compound to give an extended adhesion-improving adduct. For example, in some embodiments, the adhesion-improving adduct is a reaction product of reagents representing an adhesion-improving adduct containing a first reactive functional group, such as an adhesion-improving adduct of Formula (13); and a compound containing a second reactive functional group capable of reacting with the first reactive functional group.

In some embodiments, the adhesion-improving adduct can be reacted with a polyamine, such as diamine, or with a polythiol, such as dithiol.

In some embodiments, a compound containing a functional group capable of reacting with an adhesion-improving adduct may have the structure of Formula (17):

where each R ^{31 is} selected from functional groups capable of reacting with an adhesion-improving adduct, such as —NH ₂ , —SH, or —CH = CH ₂ ; and

each R ^{30 is} independently selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ⁶ ) _s -X-] _q - (CHR ⁶ ) _r - ;

where each R ⁶ independently selected from a hydrogen atom and methyl;

each X is independently selected from —O—, —S— and —NR—, where R is selected from a hydrogen atom and methyl;

s is an integer from 2 to 6;

q is an integer from 1 to 5; and

r is an integer from 2 to 10.

Examples of elongated adhesion-improving adducts include the reaction product of the adhesion-improving adduct of Formula (13), and the compound of Formula (17) is 3.3 '- ((oxybis (ethane-2,1-diyl)) bis (hydroxy)) bis (propane -1-amine), 2,2'-thiodiethanethiol or 2,2'-oxydiethanethiol.

In other embodiments, the adhesion-improving adduct can be reacted with a reactive functional group of the prepolymer to produce an adhesion-improving adduct-functional or terminal prepolymer. In some embodiments, the prepolymer may be a sulfur-containing prepolymer, such as any of those described herein, including polythioether prepolymers.

Polyvalent Adhesion Improving Adducts

In some embodiments, the adhesion-improving adducts are polyvalent, wherein more than one adhesion-improving adducts is associated with a common polyvalent core.

Polyvalent adhesion-improving adducts can be prepared by reacting an adhesion-improving adduct containing a reactive group with a reactive group of a polyfunctionalizing agent.

Thus, in some embodiments, the polyvalent adhesion-improving adduct comprises a reaction product of reagents comprising a z-valent polyfunctionalizing agent containing terminal functional groups capable of reacting with a functional group of an adhesion-improving adduct and an adhesion-improving adduct containing an adhesion-improving group, a ligand, able to coordinate with metal, and functional group.

An example of an adhesion-improving adduct containing a reactive group that can be reacted with a polyfunctionalizing agent includes adhesion-improving adducts derived from bis (sulfonyl) alkanol, such as the adduct of Formula (13), which have a terminal alkenyl group that can react, for example , with thiol groups of a polyfunctionalizing agent.

Examples of polyfunctionalizing agents suitable for the preparation of such polyvalent adhesion improvers include trifunctionalizing agents, that is, compounds where z is 3. Suitable trifunctionalizing agents include, for example, triallyl cyanurate (TAC), 1,2,3-propananthithiol, isocyanurate-containing tritiols, as described in US patent application No. 2010/0010133 in paragraphs [0102] to [0105], the cited fragment of which is incorporated herein by reference. Other suitable polyfunctionalizing agents include trimethylolpropane trivinyl ether and polythiols described in US Patent Nos. 4,366,307; 4,609,762 and 5,225,472. Mixtures of polyfunctionalizing agents can also be used.

In some embodiments, the polyfunctionalizing agents may have the structure B (-V) _z , where B is the core of the z-valent polyfunctionalizing agent, z is an integer from 3 to 6, and each -V is a moiety containing a terminal group capable of react with a functional group that improves the adhesion of the adduct. In some embodiments, z is 3, z is 4, z is 5, and in some embodiments, z is 6. In some embodiments, the multifunctional compound is trifunctional. In some embodiments, the multifunctional compounds are triallyl cyanurate (TAC), where B has the structure:

and each —V has the structure —O — CH ₂ —CH═CH ₂ .

In some embodiments, the multifunctional compound B (-V) _z has a molecular weight of less than 800 Da, less than 600 Da, less than 400 Da, and, in some embodiments, less than 200 Da. Polyfunctional compounds B (-V) _z , in which z is at least 3, can be any of the polyfunctionalizing agents used in polymer chemistry. Polyfunctionalizing agents having mixed functionality, i.e. agents comprising fragments (usually single fragments) that react with both thiol and vinyl groups. Other suitable polyfunctionalizing agents include trimethylolpropane trivinyl ether and polythiols as described in US Pat. No. 4,366,307, US Pat. No. 4,609,762 and US Pat. No. 5,225,472, each of which is incorporated herein by reference in its entirety. Combinations of polyfunctionalizing agents having the same terminal groups, such as thiol groups or allyl groups, can also be used.

In some embodiments, the polyvalent adhesion improving adduct has the structure of Formula (18):

where R ¹¹ contains an adhesion improving group;

P contains a core adhesion promoter;

M contains a ligand capable of coordinating with the metal;

R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ -PR ¹² and the metal chelating agent R ¹³ -MR ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ contains a reactive functional group.

R ¹⁴ 'is a fragment formed by the reaction of R ¹⁴ and V;

B represents the core of the z-valent polyfunctionalizing agent B (-V) _z , where:

z is an integer from 3 to 6; and

each -V is a group containing a group capable of reacting with R ¹⁴ ; and

each -V'- is formed by the reaction of -V with R ¹⁴ .

In some embodiments, a polyvalent adhesion-improving adduct can be formed by reacting the adhesion-improving adduct of Formula (13) with a polyfunctionalizing agent B (-V) _z , where the adhesion-improving adduct contains a functional group, such as R ⁴ , which can react with a functional group -V.

In some embodiments, the polyvalent adhesion improver adduct comprises a reaction product of reagents comprising a polyfunctionalizing agent of Formula B (-V) _z , wherein B is the core of a z-valent polyfunctionalizing agent; z is an integer from 3 to 6; and each —V is a group containing a first reactive functional group; and an adhesion improving adduct comprising an adhesion improving group, a ligand capable of coordinating with the metal, and a second functional group capable of reacting with the first reactive functional group of the polyfunctionalizing agent.

The ratio of adhesion-improving adduct and polyfunctionalizing agent can be adjusted to obtain the desired range of functionality.

Polyvalent Sulfur Adhesion Improving Adducts

In some embodiments, the adhesion-improving adduct is a polyvalent sulfur-containing adhesion-improving adduct having the structure of Formula (19);

where z is an integer from 1 to 6;

each R ^{1 is} independently selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r - ;

where each R ³ independently selected from a hydrogen atom and methyl;

each X is independently selected from —O— —S— and —NR—, where R is selected from a hydrogen atom and methyl;

s is an integer from 2 to 6;

q is an integer from 1 to 5; and

r is an integer from 2 to 10;

R ¹¹ contains an adhesion improving group;

P contains a core adhesion promoter;

M contains a ligand capable of coordinating with the metal;

R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ -PR ¹² and the metal chelating agent R ¹³ -MR ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ contains a reactive functional group.

R ^{14 '} is a fragment formed by the reaction of R ¹⁴ and a thiol group;

B represents the core of the z-valent polyfunctionalizing agent B (-V) _z , where:

z is an integer from 3 to 6; and

each -V is a group containing a group capable of reacting with a thiol group; and

each -V'- is formed by the reaction of -V with a thiol group.

In some embodiments, the polyvalent sulfur-containing adhesion-improving adduct is a reaction product of reagents, which are: (a) a polyfunctionalizing agent containing terminal groups capable of reacting with thiol groups; (b) dithiol; and (c) an adhesion improving adduct containing a functional group capable of reacting with a thiol group. In some embodiments of this reaction, the reaction products are one or more compounds of Formula (19). In polyvalent sulfur-containing adhesion-improving adducts, each or some of the chains of the polyfunctionalizing agent may be closed in the adhesion-improving adduct. In copolymerizable adhesion-improving adducts, at least one chain is capable of reacting with the copolymer and / or hardener.

In some embodiments, the implementation of a multifunctional compound containing terminal groups capable of reacting with thiol groups has the structure B (-V) _z , where z is an integer from 3 to 6, and B and -V correspond to the definitions given in this text .

In some embodiments, B (-V) _z each -V contains a terminal alkenyl group.

In some embodiments, the implementation of dithiol has the structure of Formula (20):

where R ^{1 is} selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -;

where each R ³ independently selected from a hydrogen atom and methyl;

each X is independently selected from —O—, —S— and —NR—, where R is selected from a hydrogen atom and methyl;

s is an integer from 2 to 6;

q is an integer from 1 to 5; and

r is an integer from 2 to 10.

In some embodiments, R ¹ is - [- CHR ³ ) _s —X—] _q - (CHR ³ ) _r -.

In some embodiments of the compound of Formula (20), X is selected from —O— and —S—, and thus - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r - in Formula (20) is - [(-CH ₂ -) _p -O-] _q - (CH ₂ ) _r or - [(- CH ₂ -) _p -S-] _q - (CH ₂ ) _r -. In some embodiments, p and r are equal, for example p and r are both equal to 2.

In some embodiments, R ^{1 is} selected from C _2-6 alkanediyl and - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -.

In some embodiments, R ¹ is - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -, and in some embodiments, X is —O—, and in some embodiments, X is - S-.

In some embodiments, where R ¹ is - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, p is 2, r is 2, q is 1, and X is -S- ; in some embodiments, p is 2, q is 2, r is 2, and X is —O—; and in some embodiments, p is 2, r is 2, q is 1, and X is —O—.

In some embodiments, where R ¹ is - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, each R ³ is a hydrogen atom, and in some embodiments, at least one R ³ represents methyl.

In some embodiments of the compounds of Formula (20), each R ^{1 is the} same, and in some embodiments, at least one R ¹ is different.

Examples of suitable dithiols include, for example, 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,3-butanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,3-pentanedithiol, 1 , 5-pentanedithiol, 1,6-hexanedithiol, 1,3-dimercapto-3-methylbutane, dipentene dimercaptan, ethyl cyclohexyl dithiol (ECHDT), dimercaptodiethyl sulfide, methyl substituted dimercaptodiethyl sulfide, dimethyl-substituted dimercapto-di-mercapto-di-mercapto-di-merptaptodo-di-mercapto-di-mercapto-di-merptaptodo-di-mercapto-di-mercapto-di-merptaptodo-di-mercapto-dopmerdopto oxapentane and a combination of any of the above. The polythiol may have one or more groups in the side chains selected from a lower (e.g., C _1-6 ) alkyl group, a lower alkoxy group, and a hydroxyl group. Suitable alkyl groups in the side chains include, for example, C _1-6 linear alkyl, C _3-6 branched alkyl, cyclopentyl and cyclohexyl.

Other examples of suitable dithiols include dimercaptodiethyl sulfide (DMDS) (in Formula (20), R ¹ is - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r -, where p is 2, r is 2 , q is 1, and X is —S—); dimercaptodioxa octane (DMDO) (in Formula (20), R ¹ is - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r - where p is 2, q is 2, r is 2, and X represents —O—); and 1,5-dimercapto-3-oxapentane (in Formula (20), R ¹ represents - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r -, where p is 2, r is 2, q is 1, and X is —O—). Dithiols that contain both heteroatoms in the carbon backbone and side alkyl groups such as methyl groups can also be used. Such compounds include, for example, methyl-substituted DMDS such as HS-CH ₂ CH (CH ₃ ) -S-CH ₂ CH ₂ -SH, HS-CH (CH ₃ ) CH ₂ -S-CH ₂ CH ₂ -SH and dimethyl-substituted DMDS such as HS-CH ₂ CH (CH ₃ ) -S-CHCH ₃ CH ₂ -SH and HS-CH (CH ₃ ) CH ₂ -S-CH ₂ CH (CH ₃ ) -SH.

Polyvalent sulfur-containing adhesion-improving adducts can give additional flexibility to polyvalent adhesion-improving groups, which leads to increased adhesion to the surface. In some embodiments, polyvalent sulfur-containing adhesion-improving adducts can be prepared by first reacting a polyfunctionalizing agent with a sulfur-containing compound to produce a polyfunctionalizing agent having sulfur-containing groups. The resulting intermediate can then be reacted with an adhesion-improving adduct, such as an adduct of Formula (13), having functional groups capable of reacting with sulfur-containing groups. The sulfur-containing polyfunctionalizing agent and the adhesion improving adduct can be reacted in such a way that all or some of the chains end with the adhesion improving adduct.

Copolymerizable Adhesion Improving Adducts

Adhesion-improving adducts that can be directly polymerized into the backbone of a sulfur-containing polymer can improve the adhesion of a composition, such as a sealant composition. The copolymerizable adhesion-improving adduct includes adhesion-improving groups and ligands capable of coordinating with the metal, which provides adhesion to the surface, and reactive groups capable of reacting with terminal groups of the copolymer and / or hardener. During the curing reaction, at least some of the terminal groups of the copolymer and the reactive terminal groups of the copolymerizable adhesion-improving adduct can interact with the copolymer and / or hardener, and thereby directly incorporate the copolymerizable adhesion-improving adduct into the polymer network. In other embodiments, the copolymerizable adhesion-improving adduct may include groups capable of reacting with the copolymer.

Thus, in some embodiments, the copolymerizable adhesion-improving adduct comprises a reaction product of reagents comprising an adhesion-improving adduct comprising an adhesion-improving group, a ligand capable of coordinating with the metal, and a reactive functional group; and a z-valent polyfunctionalizing agent containing functional groups capable of reacting with a functional group that improves the adhesion of the adduct; where the copolymerizable adhesion-improving adduct contains from 1 to z-1 terminal adhesion-improving adducts.

In some embodiments, the copolymerizable adhesion-improving adduct has the structure of Formula (21):

where R ¹¹ contains an adhesion improving group;

P contains a core adhesion promoter;

M contains a ligand capable of coordinating with the metal;

R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ¹³ adhesion promoter R ¹¹ -PR ¹² and metal chelating agent R ¹³ -M-R ¹⁴ where R ¹² and R ¹³ include mutually reactive functional groups , and R ¹⁴ contains a reactive functional group;

B represents the core of the z-valent polyfunctionalizing agent of Formula (22):

where z is an integer from 3 to 6;

z1 is an integer from 1 to z-1;

each —V ¹ is a group containing a first reactive functional group; and

at least one —V ² contains a second reactive functional group; and

each R ^{14 '} represents a fragment formed by the reaction of R ¹⁴ and -V ¹ ; and

each —V ^{1 ′} - is a fragment formed by the reaction of —V ¹ with R ¹⁴ .

In some embodiments, the copolymerizable adhesion improver adduct comprises a reaction product of reagents, including:

polyfunctionalizing agent of Formula (22):

Where

B represents the core of the z-valent polyfunctionalizing agent B (-V) _z , where:

z is an integer from 3 to 6;

z1 is an integer from 1 to z-1;

each —V ¹ is a group containing a first reactive functional group; and

at least one —V ² contains a second reactive functional group; and

adhesion-improving adduct containing an adhesion-improving group, a ligand capable of coordinating with the metal, and a third functional group capable of reacting with the first reactive functional group.

In some embodiments, V ¹ and V ^{2 are the} same, and in some embodiments, V ¹ and V ² are different. In some embodiments, V ¹ and V ² contain the same reactive functional group, and in some embodiments, V ¹ and V ² contain different reactive functional groups. In some embodiments, each V ^{2 is} selected so that it is capable of reacting with a hardener, prepolymer, or a combination thereof. In some embodiments, each V ² contains the same reactive group as the prepolymer-forming composition.

Copolymerizable adhesion-improving adducts include at least some groups capable of reacting with a hardener or copolymer, such as from 2 to 5 groups capable of reacting with a hardener and / or copolymer.

Copolymerizable Sulfur Adhesion Improving Adducts

In some embodiments, the copolymerizable adhesion-improving adduct may be a copolymerizable sulfur-containing adhesion-improving adduct. Copolymerizable sulfur-containing adhesion promoters are described in US Patent Application No. 13 / 529,183. These copolymerizable sulfur-containing adhesion-improving adducts contain a sulfur-containing group bonded to a polyfunctional core, where at least some of the sulfur-containing groups have a group at the ends that is capable of reacting with a hardener or prepolymer, and the remaining groups have an adhesion-improving adduct at the ends.

Embodiments of the present invention include copolymerizable adhesion promoters similar to those described in US patent application No. 13 / 529,183, where the adhesion improving adduct of the present invention replaces at least some or all of the adhesion promoters described in this application.

Thus, in some embodiments, the copolymerizable sulfur-containing adhesion-improving adduct comprises a reaction product of reagents including dithiol; a polyfunctionalizing agent containing functional groups capable of reacting with thiol groups; and an adhesion improving adduct comprising an adhesion improving group, a ligand capable of coordinating with a metal, and a group capable of reacting with a thiol group. In some embodiments, compounds other than dithiols may be used to introduce sulfur-containing groups into the adduct.

In some embodiments, the copolymerizable sulfur-containing adhesion-improving adduct has the structure of Formula (23):

where each R ^{1 is} independently selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -;

where each R ³ independently selected from a hydrogen atom and methyl;

each X is independently selected from —O—, —S— and —NR—, where R is selected from a hydrogen atom and methyl;

s is an integer from 2 to 6;

q is an integer from 1 to 5; and

r is an integer from 2 to 10;

R ¹¹ contains an adhesion improving group;

P contains a core adhesion promoter;

M contains a ligand capable of coordinating with the metal;

R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ -PR ¹² and the metal chelating agent R ¹³ -MR ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ contains a reactive functional group;

R ^{14 '} is a fragment formed by the reaction of R ¹⁴ and a thiol group;

B represents the core of the z-valent polyfunctionalizing agent B (-V) _z , where

z is an integer from 3 to 6;

z1 is an integer from 1 to z-1; and

each -V is a group containing a group capable of reacting with a thiol group; and

each -V'- is formed by the reaction of -V with a thiol group.

In some embodiments, the copolymerizable sulfur-containing adhesion-improving adduct comprises a reaction product of reagents including dithiol; a polyfunctionalizing agent containing functional groups capable of reacting with thiol groups; and an adhesion improving adduct according to claim 1, containing functional groups capable of reacting with thiol groups.

In some embodiments, the copolymerizable adhesion enhancing adducts described herein can be copolymerized by incorporating a sulfur-containing polymer, such as a thiol-terminal sulfur-containing polymer, including, for example, thiol-terminal polythioesters and thiol-terminal polysulfides.

In some embodiments, the adhesion improving adduct can be copolymerized into a thiol terminal polythioether polymer. Examples of thiol-functional polythioethers are described, for example, in US Pat. No. 6,172,179. In some embodiments, the thiol-functional polythioether is Permapol® P3.1E, available from PRC-DeSoto International Inc., Sylmar, CA.

In some embodiments, the adhesion-improving adduct can be copolymerized into a polysulfide polymer. In some embodiments, the polysulfide polymer may be any of the polymers described, for example, in US Pat. No. 4,623,711.

The compounds of Formulas (21) and (23) contain at least one terminal adhesion-improving adduct and at least two terminal thiol groups. Said at least one adherence improving adduct provides adhesion to the surface and / or other components of the composition of which it is a part, and terminal thiol groups react with a hardener to form a polymer network. Thus, in the compounds of Formulas (21) and (23), z2 is at least 2, and in some embodiments, z2 is 2, 3, 4, and in some embodiments, z2 is 5. In some embodiments of the compounds of Formula (21) and (23) z1 is 1, 2, 3, and in some embodiments, z1 is 4. In some embodiments, the compound of Formula (21) and (17) is trivalent, so z is 3, in some embodiments, the compound of Formula ( 21) and (23) is tetravalent, so z is 4, and in some embodiments, z is 5, and in some toryh embodiments, z is equal to 6.

In some embodiments of Formulas (21) and (23), R ^{1 is} selected from C _2-6 alkanediyl and - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -.

In some embodiments of Formulas (21) and (23), R ¹ is - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -, and in some embodiments, X is —O—, and in some embodiments, X is —S—.

In some embodiments of Formulas (21) and (23), where R ¹ is - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, p is 2, r is 2, q is 1, and X represents —S—; in some embodiments, p is 2, q is 2, r is 2, and X is —O—; and in some embodiments, p is 2, r is 2, q is 1, and X is —O—.

In some embodiments of Formulas (21) and (23), where R ¹ represents - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -, each R ³ represents a hydrogen atom, and in some embodiments the implementation of at least one R ³ represents methyl.

In some embodiments of the compounds of Formulas (21) and (23), each R ^{1 is the} same, and in some embodiments, at least one R ¹ is different.

In some embodiments of the compounds of Formulas (21) and (23), a terminal group capable of reacting with a thiol group in compound A is selected from an alkenyl group, an isocyanate group, an epoxy group, a Michael acceptor group, and a group containing a saturated carbon atom bearing a leaving group well suited for nucleophilic substitution, such as, for example, —Cl, —Br, —I, —OSO ₂ CH ₃ (mesylate), —OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate), etc. . In some embodiments of the compounds of Formulas (21) and (23), a terminal group capable of reacting with a thiol group in compound A includes an alkenyl group, an isocyanate group, an epoxy group, a Michael acceptor group, and in some embodiments, a saturated moiety group a carbon atom bearing a leaving group well suited for nucleophilic substitution, such as, for example, —Cl, —Br, —I, —OSO ₂ CH ₃ (mesylate), —OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate) etc.

In some embodiments of the compounds of Formulas (21) and (23), the terminal adhesion promoting group is selected from polyalkoxysilyl, phosphonate, amine, carboxylic acid and phosphonic acid. In some embodiments of the compounds of Formulas (21) and (23), the terminal adhesion promoting group is a polyalkoxysilyl group, a phosphonate group, an amino group, a carboxyl group, and in some embodiments, a phosphonic acid group.

In some embodiments of the compounds of Formulas (21) and (23), a ligand capable of coordinating with a metal is selected from any of those described herein.

In some embodiments, -V is a moiety containing a terminal group capable of reacting with a thiol group. For example, in some embodiments, —V is —R ¹⁰ —CH═CH ₂ , where R ^{10 is} selected from C _1-6 alkanediyl, substituted alkanediyl, C _1-6 heteroalkanediyl and substituted C _1-6 heteroalkanediyl. However, the -V structure has no limitations. In some embodiments, each -V may be the same, and in some embodiments, at least one -V may be different.

In some embodiments of the compounds of Formulas (21) and (23), all groups of the adhesion improving adduct are the same and are selected from Formula (24a), Formula (24b), Formula (24c) and Formula (24d):

where each R ¹⁰ represents C _2-8 alkanediyl, y1 is selected from 0, 1 and 2; y2 is selected from 1, 2, and 3; where the sum of y1 and y2 is 3; each R ⁵ and R ^{6 is} independently selected from C _1-4 alkyl; and R ^{8 is} selected from a hydrogen atom and C _1-4 alkyl.

In some embodiments of the compounds of Formulas (21) and (23), each -A 'is the same and represents a fragment of Formula (24a), a fragment of Formula (24b), a fragment of Formula (24c), and in some embodiments, a fragment of Formula (24d).

In the copolymerizable sulfur-containing adhesion-improving adducts of Formula (21) and Formula (23), B is the core of the z-valent polyfunctional compound B (-V) _z , where z is an integer from 3 to 6. In some embodiments, z is 3, z is 4, z is 5, and in some embodiments, z is 6. In some embodiments, the multifunctional compound is trifunctional. In some embodiments, the polyfunctional compound is triallyl cyanurate (TAC), where B has the structure:

and each —V has the structure —O — CH ₂ —CH═CH ₂ .

In some embodiments, the polyfunctional compound B (-V) _z has a molecular weight of less than 800 Da, less than 600 Da, less than 400 Da, and in some embodiments less than 200 Da. Polyfunctional compounds B (-V) _z , in which z is at least 3, can be any of the polyfunctionalizing agents used in polymer chemistry. Polyfunctionalizing agents having mixed functionality, i.e. agents comprising fragments (usually single fragments) that react with both thiol and vinyl groups. Other suitable polyfunctionalizing agents include trimethylolpropane trivinyl ether and polythiols as described in US Pat. No. 4,366,307, US Pat. No. 4,609,762 and US Pat. No. 5,225,472, each of which is incorporated herein by reference in its entirety. Combinations of polyfunctionalizing agents having the same terminal groups, such as thiol groups or allyl groups, can also be used.

In some embodiments, each -V is a moiety containing a terminal group capable of reacting with a thiol group, such as, for example, an alkenyl group, an epoxy group, a Michael acceptor group, or a group containing a saturated carbon atom carrying a leaving group, well suited for nucleophilic substitution, such as, for example, —Cl, —Br, —I, —OSO ₂ CH ₃ (mesylate), —OSO ₂ —C ₆ H ₄ —CH ₃ (tosylate), etc. In some embodiments, each −V is the same and in some embodiments, at least one −V is different. In some embodiments, —V is selected from C _3-8 alkene-1-yl and C _3-8 heteroalken-1-yl, wherein one or more hetero groups are selected from —O— and —S—.

Each —V— is a fragment obtained by reacting a —V fragment with a thiol group. In some embodiments, -V contains a terminal alkenyl group selected from C _3-8 alken-1-yl and C _3-8 heteroalken-1-yl, and V is selected from C _3-8 alkanediyl and C _3-8 heteroalkanediyl.

In some embodiments, the polyfunctionalizing agent having terminal groups capable of reacting with thiol groups has the structure B (-V) _z , where z is an integer from 3 to 6, and B and -V are as defined herein .

In some embodiments, B (-V) _z each -V contains a terminal alkenyl group.

In some embodiments, a copolymerizable sulfur-containing adhesion promoter of Formula (23) is a reaction product of (a) a polyfunctionalizing agent having terminal groups capable of reacting with thiol groups; (b) dithiol; and (c) an adhesion-improving adduct having a functional group capable of reacting with a thiol group. In some embodiments of the reaction, the reaction products contain one or more compounds of Formula (23). A polyfunctionalizing agent and an adhesion improver can be, for example, any of those described herein, and the dithiol can be a dithiol of Formula (20).

In some embodiments, the implementation of dithiol has the structure of Formula (20):

where R ^{1 is} selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -;

where each R ³ independently selected from a hydrogen atom and methyl;

each X is independently selected from —O—, —S— and —NR—, where R is selected from a hydrogen atom and methyl;

s is an integer from 2 to 6;

q is an integer from 1 to 5; and

r is an integer from 2 to 10.

In some embodiments, R ¹ is - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -.

In some embodiments of the compound of Formula (20), X is selected from —O— and —S—, and thus - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r - in Formula (20) is - [(-CH ₂ -) _p -O-] _q - (CH ₂ ) _r - or - [(- CH ₂ -) _p -S-] _q - (CH ₂ ) _r -. In some embodiments, p and r are equal, for example p and r are both equal to 2.

In some embodiments, R ^{1 is} selected from C _2-6 alkanediyl and - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -.

In some embodiments, R ¹ is - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r - and in some embodiments, X is —O— and in some embodiments, X is —S— .

In some embodiments, where R ¹ is - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, p is 2, r is 2, q is 1, and X is -S- ; in some embodiments, p is 2, q is 2, r is 2, and X is —O—; and in some embodiments, p is 2, r is 2, q is 1, and X is —O—.

In some embodiments, where R ¹ is - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, each R ³ is a hydrogen atom, and in some embodiments, at least one R ³ represents methyl.

In some embodiments of the compounds of Formula (20), each R ^{1 is the} same, and in some embodiments, at least one R ¹ is different.

Examples of suitable dithiols include, for example, 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,3-butanedithiol, 1,4-butanedithiol, 2,3-butanedithiol, 1,3-pentanedithiol, 1 , 5-pentanedithiol, 1,6-hexanedithiol, 1,3-dimercapto-3-methylbutane, dipentene dimercaptan, ethyl cyclohexyl dithiol (ECHDT), dimercaptodiethyl sulfide, methyl substituted dimercaptodiethyl sulfide, dimethyl-substituted dimercapto-di-mercapto-di-mercapto-di-merptaptodo-di-mercapto-di-mercapto-di-merptaptodo-di-mercapto-di-mercapto-di-merptaptodo-di-mercapto-dopmerdopto oxapentane and a combination of any of the above. A polythiol may have one or more groups in the side chains selected from a lower (e.g., C _1-6 ) alkyl group, a lower alkoxy group, and a hydroxyl group. Suitable alkyl groups in the side chains include, for example, C _1-6 linear alkyl, C _3-6 branched alkyl, cyclopentyl and cyclohexyl.

Other examples of suitable dithiols include dimercaptodiethyl sulfide (DMDS) (in Formula (20), R ¹ is - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r -, where p is 2, r is 2, q is 1, and X is —S—); dimercaptodioxa octane (DMDO) (in Formula (20), R ¹ is - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r -, where p is 2, q is 2, r is 2, and X represents —O—); and 1,5-dimercapto-3-oxapentane (in Formula (20), R ¹ is - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r -, where p is 2, r is 2 , q is 1, and X is —O—). Dithiols that contain both heteroatoms in the carbon backbone and side alkyl groups such as methyl groups can also be used. Such compounds include, for example, methyl-substituted DMDS such as HS-CH ₂ CH (CH ₃ ) -S-CH ₂ CH ₂ -SH, HS-CH (CH ₃ ) CH ₂ -S-CH ₂ CH ₂ -SH and dimethyl-substituted DMDS such as HS-CH ₂ CH (CH ₃ ) -S-CHCH ₃ CH ₂ -SH and HS-CH (CH ₃ ) CH ₂ -S-CH ₂ CH (CH ₃ ) -SH.

In some embodiments of the reaction to form a copolymerizable sulfur-containing adhesion-improving adduct, a polyfunctionalizing agent and a dithiol can be reacted to form a thiol terminal intermediate. In this case, the molar ratio of the reactants is suitably selected. For example, one mole of a trifunctional compound such as TAC can be reacted with three moles of a dithiol, such as DMDO, to give a trifunctional thiol-terminal intermediate. The trifunctional thiol-terminal intermediate can then be reacted with a compound containing a group capable of reacting with a thiol group and an adhesion promoting group. The molar ratio of the intermediate to the compound containing a group capable of reacting with the thiol group and the adhesion enhancing group can be selected to obtain a multifunctional compound having a target average functionality of a sulfur-containing adduct that improves adhesion. For example, to obtain an average adhesion promoter functionality of about 1, about one mole of the polyfunctional intermediate is reacted with about 1 mole of a compound containing a terminal group capable of reacting with a thiol group and a terminal group that enhances adhesion.

The copolymerizable sulfur-containing adhesion-improving adducts described in the present invention, it is understood that the compounds contain at least one terminal group that enhances adhesion, and at least two terminal groups, such as terminal thiol groups, capable of reacting with a hardener, and therefore can be included in the main chain of the polymer network, for example, enter into a copolymerization reaction. In some embodiments, the sulfur-containing compound contains, on average, a single adhesion-improving group per molecule, and in some embodiments, on average, two adhesion-improving groups per molecule.

In some embodiments, the copolymerizable sulfur-containing adhesion-improving adduct is the reaction products of triallyl cyanurate reagents, DMDO and the adhesion-improving adduct described herein.

Songs

The adhesion improving adducts described herein can be used in polymer compositions, such as sealant compositions used in the aerospace industry.

Adhesion improving adducts, such as adducts of Formulas (13), Formulas (18), Formulas (19), Formulas (21), Formulas (23), or a combination of any of the above, can be used in the compositions as adhesion improvers. In some embodiments, the adhesion-improving adduct is, for example, from 1 weight. % to 50 weight. %, from 5 weight. % to 30 weight. %, or from 1 weight. % to 10 weight. % by weight of the composition.

In other embodiments, the adhesion-improving adduct is copolymerizable, such as the adducts of Formula (21) and (23), and the copolymerizable adhesion-improving adduct together with a copolymer and / or hardener having suitable chemical properties are included in the cured polymer.

The compositions may also contain a combination of one or more adhesion-improving adducts and / or copolymerizable adhesion-improving adducts described herein.

For use in the sealant for the aerospace industry, the composition may contain a sulfur-containing polymer. In some embodiments, the sulfur-containing prepolymer is a thiol-terminal sulfur-containing prepolymer selected from a thiol-terminal polythioether prepolymer, a thiol-terminal polysulfide prepolymer, a thiol-terminal sulfur-containing polyformal prepolymer, and a combination of any of the above. In some embodiments, the sulfur-containing prepolymer is a thiol-terminal polythioether prepolymer.

In some embodiments, the thiol-terminal sulfur-containing polymer is a thiol-terminal polythioether. The thiol terminal polythioether may be a mixture of different polythioethers, and these polythioethers may have the same or different functionality of thiol groups. In some embodiments, the thiol-terminal polythioether has an average functionality of 2 to 6, 2 to 4, 2 to 3, and in some embodiments, 2.05 to 2.8. For example, a thiol terminal polythioether may be selected from a difunctional sulfur-containing polymer, a trifunctional sulfur-containing polymer, and combinations thereof.

Examples of thiol-functional polythioethers are described, for example, in US Pat. No. 6,172,179. In some embodiments, the thiol functional polythioether is Permapol® P3.1E, available from PRC-DeSoto International Inc., Sylmar, CA.

In some embodiments, a thiol terminal polythioether comprises (a) a backbone having the structure of Formula (25):

where (i) each R ^{1 is} independently selected from a C _2-10 n-alkanediyl group, a C _3-6 branched alkanediyl group, a C _6-8 cycloalkanediyl group, a C _6-10 alkanocycloalkanediyl group, a heterocyclic group, - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r - groups and - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r - groups in which at least one -CH ₂ - the fragment is substituted by a methyl group; (ii) each R ^{2 is} independently selected from a C _2-10 n-alkanediyl group, a C _3-6 branched alkanediyl group, a C _6-8 cycloalkanediyl group, a C _6-14 alkanocycloalkanediyl group, a heterocyclic group, and - [(- CH ₂ - ) _p —X—] _q - (CH ₂ ) _r are groups; (iii) each X is independently selected from an O, S, and —NR— group in which R is selected from a hydrogen atom and a methyl group; (iv) m is in the range from 0 to 50; (v) n is an integer from 1 to 60; (vi) p is an integer from 2 to 6; (vii) q is an integer from 1 to 5; and (viii) r is an integer from 2 to 10.

In some embodiments, the thiol-terminal polythioether is selected from the thiol-terminal polythioether of Formula (26a), the thiol-terminal polythioether of Formula (26b), and combinations thereof:

where each R ^{1 is} independently selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [(- CHR ³ -) _s -X-] _q - (- CHR ³ -) _r -,

where s is an integer from 2 to 6;

q is an integer from 1 to 5;

r is an integer from 2 to 10;

each R ³ is independently selected from hydrogen and methyl; and

each X is independently selected from O, S and —NHR—, where R is selected from a hydrogen atom and methyl;

each R ^{2 is} independently selected from C _1-10 alkanediyl, C _6-8 cycloalkanediyl, C _6-14 alkanocycloalkanediyl and - [(- CHR ³ -) _s -X-] _q - (- CHR ³ -) _r -, where s , q, r, R ³ and X correspond to the definitions given above;

m is an integer from 0 to 50;

n is an integer from 1 to 60;

p is an integer from 2 to 6;

B is the core of the z-valent, polyfunctional compound B (-V) _z

where z is an integer from 3 to 6; and

each -V is a moiety containing a terminal group capable of reacting with a thiol group; and

each -V'- is a fragment obtained by the reaction of each -V with a thiol group.

In some embodiments, the implementation of R ¹ in Formula (26a) and in Formula (26b) represents - [(- CH ₂ -) _p -X-] _q - (CH ₂ ) _r -, where p is 2, X represents - O-, q is 2, r is 2, R ² is ethanediyl, m is 2, and n is 9.

In some embodiments of Formulas (26a) and Formulas (26b), R ^{1 is} selected from C _2-6 alkanediyl and - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r -.

In some embodiments of Formula (26a) and Formula (26b), R ¹ is - [- (CHR ³ ) _s —X—] _q - (CHR ³ ) _r - and in some embodiments, X is —O—, and in some embodiments, X is —S—.

In some embodiments of Formula (26a) and Formula (26b), where R ¹ is - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, p is 2, r is 2, q is 1 , and X represents —S—; in some embodiments, p is 2, q is 2, r is 2, and X is —O—; and in some embodiments, p is 2, r is 2, q is 1, and X is —O—.

In some embodiments of Formula (26a) and Formula (26b), where R ¹ represents - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -, each R ³ represents a hydrogen atom, and in some embodiments, at least one R ³ is methyl.

In some embodiments, the compounds of Formulas (26a) and Formulas (26b) each R ^{1 is the} same, and in some embodiments, at least one R ¹ is different.

You can apply various methods for producing such polythioethers. Examples of suitable thiol-functional polythioesters and methods for their preparation, suitable for use in the compositions described herein, are described in US Pat. No. 6,172,179 per col. 2, line 29 - count. 4, line 22; count 6, line 39 - count. 10, line 50; and count 11, line 65 - count. 12, line 22, cited fragments of which are incorporated herein by reference. Such thiol-functional polythioethers can be difunctional, that is, linear polymers having two terminal thiol groups, or polyfunctional, that is, branched polymers having three or more terminal thiol groups. Such thiol-functional polythioethers are commercially available, for example, under the brand name Permapol® P3,1E from PRC-DeSoto International Inc., Sylmar, CA.

Suitable thiol-functional polythioethers can be prepared by reacting a divinyl ether or a mixture of divinyl ethers with an excess of dithiol or a mixture of dithiols. For example, dithiols suitable for use in the preparation of such thiol-functional polythioethers include dithiols having Formula (20), other dithiols described herein, or combinations of any of the dithiols described herein.

Suitable divinyl esters include, for example, divinyl esters having Formula (27):

where R ² in Formula (27) is selected from a C _2-6 n-alkanediyl group, a C _3-6 branched alkanediyl group, a C _6-8 cycloalkanediyl group, a C _6-10 alkanocycloalkanediyl group, and - [(- CH ₂ -) _p -O-] _q - (- CH ₂ -) _r -, where p is an integer from 2 to 6, q is an integer from 1 to 5, and r is an integer from 2 to 10. In some embodiments divinyl ether of Formula (27) R ² represents a C _2-6 n-alkanediyl group, C _3-6 branched alkanediyl group, C _6-8 cycloalkanediyl group, C _6-10 alkantsikloalkandiilnuyu group, and in some variation max of - [(- CH _{2 -) p -O-] q - (} - CH ₂ -) _r -.

Suitable divinyl esters include, for example, compounds having at least one hydroxyalkanediyl group, for example 1-4 hydroxyalkanediyl groups, i.e. compounds in which m in Formula (27) is an integer from 1 to 4. In some embodiments, m in Formula (27) is an integer from 2 to 4. Commercially available mixtures of divinyl esters having a non-integer average can also be used. the number of hydroxyalkanediyl moieties per molecule. So, m in Formula (27) can also take rational values from 0 to 10.0, such as from 1.0 to 10.0, from 1.0 to 4.0, or from 2.0 to 4.0.

Examples of suitable divinyl esters include, for example, divinyl ether, ethylene glycol divinyl ether (EG-DVE) (R ² in Formula (27) is ethanediyl, and m is 1), butanediol divinyl ether (BD-DVE) (R ² in Formula (27) is butanediyl and m is 1), hexanediol divinyl ether (HD-DVE) (R ² in Formula (27) is hexanediyl and m is 1), diethylene glycol divinyl ether (DEG-DVE) (R ² in Formula (27) represents ethanediyl, and m is 2), triethylene glycol divinyl ether (R ² in Formula (27) represents ethanediyl and m is 3), tetraethyl glycol divinyl ether (R ² in Formula (27) represents ethanediyl and m is 4), cyclohexanedimethanol divinyl ether, polytetrahydrofuryl divinyl ether; trivinyl ether monomers such as trimethylolpropane trivinyl ether; tetrafunctional ether monomers such as pentaerythritol tetravinyl ether; and combinations of two or more such polyvinyl ether monomers. The polyvinyl ether may have one or more side groups selected from alkyl groups, a hydroxyl group, an alkoxy group and an amino group.

In some embodiments, the implementation of divinyl esters in which R ² in Formula (27) is a C _3-6 branched alkanediyl can be prepared by reacting a polyhydroxy compound with acetylene. Examples of divinyl esters of this type include compounds in which R ² in Formula (27) represents an alkyl-substituted methanediyl group such as —CH (CH ₃ ) - (e.g., Pluriol® mixtures such as Pluriol® E-200 divinyl ether ( BASF Corp., Parsippany, NJ) for which R ² in Formula (27) is ethanediyl and m is 3.8) or an alkyl substituted ethanediyl (e.g. -CH ₂ CHCH ₃ ) - such as polymer mixtures DPE including DPE-2 and DPE-3 (International Specialty Products, Wayne, NJ)).

Other suitable divinyl esters include compounds in which R ² in Formula (27) is polytetrahydrofuryl (poly-THF) or polyoxyalkanediyl, such as compounds containing on average about 3 monomer fragments.

Two or more types of polyvinyl ether monomers of Formula (27) can be used. So, in some embodiments, two dithiols of Formula (20) and one polyvinyl ether monomer of Formula (27), one dithiol of Formula (20) and two polyvinyl ether monomers of Formula (27), two dithiol of Formula (20) and two divinyl ether monomers of Formula ( 27), and more than two compounds having one or more formulas for the preparation of various thiol-functional polythioethers.

In some embodiments, the polyvinyl ester monomer comprises from 20 to less than 50 mole percent of the reagents used to prepare the thiol-functional polythioether, and, in some embodiments, from 30 to less than 50 mole percent.

In some embodiments described herein, the relative amounts of dithiols and divinyl esters are selected so as to obtain terminal thiol groups. Thus, a dithiol of Formula (20) or a mixture of at least two different dithiols of Formula (20) is reacted with a divinyl ester of Formula (27) or a mixture of at least two different divinyl esters of Formula (27) in such relative quantities that the molar the ratio of thiol groups to vinyl groups was higher than 1: 1, for example from 1.1: 1.0 to 2.0: 1.0.

The reaction between dithiols and divinyl esters can be catalyzed by a free radical catalyst. Suitable free radical catalysts include, for example, azo compounds, for example azobisnitriles, such as azo (bis) isobutyronitrile (AIBN); organic peroxides such as benzoyl peroxide and tert-butyl peroxide; and inorganic peroxides, such as hydrogen peroxide. The catalyst may be a free radical catalyst, an ionic catalyst, or ultraviolet radiation. In some embodiments, the implementation of the catalyst does not contain acidic or basic compounds and does not give acidic or basic compounds when decomposed. Examples of free radical catalysts include azo-type catalysts such as Vazo®-57 (Du Pont), Vazo®-64 (Du Pont), Vazo®-67 (Du Pont), V-70® (Wako Specialty Chemicals) and V-65B® (Wako Specialty Chemicals). Examples of other free radical catalysts are alkyl peroxides, such as tert-butyl peroxide. The reaction can also be accelerated by irradiation with ultraviolet light, with or without cationic photoinitiating moiety.

The thiol-functional polythioethers described herein can be obtained by combining at least one compound of Formula (20) and at least one compound of Formula (27), followed by the addition of a suitable catalyst and carrying out the reaction at a temperature of from 30 ° C to 120 ° C, for example at 70 ° C-90 ° C, for 2-24 hours, for example 2-6 hours.

As described herein, thiol terminal polythioethers can be a polyfunctional polythioether, i.e. may have an average functionality of more than 2.0. Suitable multifunctional thiol terminal polythioethers include, for example, compounds having the structure of Formula (28):

where (i) A is the structure of Formula (28), (ii) B is a z-valent residue of a polyfunctionalizing agent; and (iii) z has an average value above 2.0, and in some embodiments, the value is between 2 and 3, the value is between 2 and 4, the value is between 3 and 6, and in some embodiments, is an integer from 3 to 6.

Polyfunctionalizing agents suitable for use in the preparation of such polyfunctional thiol functional polymers include trifunctionalizing agents, that is, compounds wherein z is 3. Suitable trifunctionalizing agents include, for example, triallyl cyanurate (TAC), 1,2,3-propananthithiol, isocyanurate-containing tritiols and combinations thereof, as described in US patent application No. 2010/0010133 in paragraphs [0102] to [0105], the cited fragment of which is incorporated herein by reference. Other suitable polyfunctionalizing agents include trimethylolpropane trivinyl ether and polythiols described in US patent No. 4,366,307; 4,609,762 and 5,225,472. Mixtures of polyfunctionalizing agents can also be used.

As a result, thiol-functional polythioethers suitable for use in the embodiments described herein may have a wide range of average functionality. For example, trifunctionalizing agents can provide average functionality from 2.05 to 3.0, for example from 2.1 to 2.6. A wider range of average functionality can be achieved using tetrafunctional polyfunctionalizing agents or polyfunctionalizing agents with an even higher value of functionality. Functionality can also be influenced by factors such as stoichiometry, which will be understood by qualified specialists in this field.

Thiol-functional polythioethers having a functionality greater than 2.0 can be prepared analogously to difunctional thiol-functional polythioethers as described in US Patent Application No. 2010/0010133. In some embodiments, polythioethers can be prepared by combining (i) one or more dithiols described herein with (ii) one or more divinyl esters described herein, and (iii) one or more polyfunctionalizing agents. Then, a reaction takes place in the mixture, optionally in the presence of a suitable catalyst, to obtain a thiol-functional polythioether having a functionality greater than 2.0.

Thus, in some embodiments, the thiol terminal polythioether comprises a reaction product of reagents, including:

(a) dithiol of Formula (20):

where R ^{1 is} selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -;

where each R ³ independently selected from a hydrogen atom and methyl;

each X is independently selected from -O-, -S-, -NH- and -NR-,

where R is selected from a hydrogen atom and methyl;

s is an integer from 2 to 6;

q is an integer from 1 to 5; and

r is an integer from 2 to 10; and

(b) divinyl ether of Formula (27):

where each R ^{2 is} independently selected from C _1-10 alkanediyl, C _6-8 cycloalkanediyl, C _6-14 alkanocycloalkanediyl and - [(- CHR ³ -) _s -X-] _q - (- CHR ³ -) _r -, where s, q, r, R ³ and X correspond to the definitions given above;

m is an integer from 0 to 50;

n is an integer from 1 to 60; and

p is an integer from 2 to 6.

And in some embodiments, the reagents include (c) a polyfunctional compound, such as a polyfunctional compound B (-V) _z , where B, -V and z are as defined herein.

The thiol terminal polythioethers described herein are thiol terminal polythioethers having a molecular weight distribution. In some embodiments, the implementation of thiol-terminal polythioethers that can be used in the described compositions can have a number average molecular weight in the range from 500 Da to 20,000 Da, in some embodiments from 2,000 Da to 5,000 Da, and in some embodiments from 3,000 Da to 4000 Yes. In some embodiments, the thiol-terminal polythioethers that can be used in the compositions described herein have a polydispersity (M _w / M _n ; weight average molecular weight / number average molecular weight) in the range of 1 to 20, and in some embodiments, 1 up to 5. The distribution of molecular weights for thiol-terminal polythioethers can be determined by gel permeation chromatography.

Curable compositions may further comprise a hardener. The compositions may further contain additives, catalysts, fillers and / or other sulfur-containing prepolymers, including, for example, polythioethers, sulfur-containing polyformals and / or polysulfides.

A suitable hardener is selected so that it can react with the terminal groups of the bis (sulfonyl) alkanol-containing polythioether and, optionally, sulfur-containing prepolymers.

In some embodiments, wherein the bis (sulfonyl) alkanol-containing polythioether or prepolymer thereof has terminal thiol groups, a suitable hardener is polyepoxide. Examples of suitable polyepoxides include, for example, polyepoxide resins, such as hydantoin diepoxide, diglycidyl ether of bisphenol-A, diglycidyl ether of bisphenol-F, epoxides type Novolac ^®, such as DEN ™ 438 (Dow Chemical Company), some of the epoxidized unsaturated resins, and combinations of any of the listed components. Polyepoxide is a compound containing two or more reactive epoxy groups. In some embodiments, the epoxy hardener is selected from EPON ™ 828 (Momentive Specialty Chemicals, Inc), DEN ™ 431 (Dow Chemical Company), and combinations thereof. Examples of suitable hardeners capable of reacting with thiol groups include diepoxides.

Other examples of suitable hardeners capable of reacting with terminal epoxy groups include amines such as diethylenetriamine (DTA), triethylenetetramine (TTA), tetraethylene pentamine (TEPA), diethylaminopropylamine (DEAPA), N-aminoethylpiperazine (N-AEP), IPOPDA ), m-xyldiamine, diaminodiphenylmethane (DDM), diaminodiphenylsulfone (DDS); aromatic amines, ketimine; polyamines; polyamides; phenolic resins; anhydrides such as phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate, glycerol tristrimellitate, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophytrophytropylene; polymercaptans; polysulfides; and other hardeners known to those skilled in the art.

In some embodiments, the polyepoxide hardener is an epoxy functional polymer. Examples of suitable epoxy-functional polymers include the epoxy-functional sulfur-containing polyformal polymers described in US patent application No. 13 / 050,988, and the epoxy-functional polythioether polymers described in US patent No. 7,671,145. In general, when used as a hardener, an epoxy-functional polymer has a molecular weight of less than about 2000 Da, less than about 1500 Da, less than about 1000 Da, and in some embodiments, less than about 500 Da.

In some embodiments, the polyepoxide may be from about 0.5 weight. % to 20 wt.% of the composition, from about 1 wt.% to 10 wt.%, from about 2 wt.% to 8 wt.%, from about 2 wt.% to 6 wt.%, and in some embodiments, from about 3 wt.% To 5 wt.%, Where percent by weight are calculated relative to the total weight of the solid residue of the composition.

In some embodiments, in which the bis (sulfonyl) alkanol-containing polythioether or prepolymer has terminal thiol groups, a suitable hardener is an unsaturated compound such as an acrylic or methacrylic ester of a polyol, unsaturated synthetic or natural resinous compounds, triallyl cyanurate and olefin terminal derivatives of sulfur compounds such as polythioethers.

In some embodiments, such as when amine and / or hydroxyl-terminal bis (sulfonyl) alkanol-containing polythioethers or prepolymers are used, the compositions described herein may contain an isocyanate hardener, such as a diisocyanate and / or triisocyanate hardener. Examples of suitable isocyanate hardeners include toluene diisocyanate and combinations of any of these components. Isocyanate hardeners are commercially available and include, for example, products under the trademarks Baydur ^® (Bayer MaterialScience), Desmodur ^® (Bayer MaterialScience), Solubond ^® (DSM), ECCO (ECCO), Vestanat ^® (Evonik), Irodur ^® (Huntsman), Rhodocoat ™ (Perstorp) and Vanchem ^® (VT Vanderbilt). In some embodiments, the polyisocyanate hardener contains isocyanate groups that are capable of reacting with thiol groups and which are less reactive with Michael acceptor groups. Examples of suitable hardeners capable of reacting with amino groups include polymeric polyisocyanates, non-limiting examples of which include polyisocyanates having backbones selected from urethane bonds (-NH-C (O) -C) -), thiourethane bonds (-NH-C (O) -S-), thiocarbamate bonds (-NH-C (S) -O-), dithiourethane bonds (-NH-C (S) -S-), and combinations of any of the listed components.

In some embodiments, the isocyanate hardener is an isocyanate-functional polymer. Examples of suitable isocyanate-functional polymers include isocyanate-functional sulfur-containing polyformal polymers described in US patent application No. 13/051,002. In general, when used as a hardener, the isocyanate-functional polymer has a molecular weight of less than about 2000 Da, less than about 1500 Da, less than about 1000 Da, and in some embodiments less than about 500 Da.

In such compositions, the isocyanate hardener may be from about 0.5 weight. % to 20 wt.% the composition, from about 1 weight. % to 10 weight. %, from about 2 wt.% to 8 wt.%, from about 2 wt.% to 6 wt.%, and in some embodiments, from about 3 wt.% to 5 wt.% of the composition, where percent by weight are calculated relative to total weight of the solid residue of the composition.

In some embodiments, such as when isocyanate-terminal bis (sulfonyl) alkanol-containing polythioethers or prepolymers thereof are used, the compositions described herein contain an amine hardener. Examples of suitable hardeners capable of reacting with isocyanate groups include diamines, polyamines, polythiols and polyols, including those described herein.

In some embodiments, such as when bis (sulfonyl) alkanol-containing polythioethers or their prepolymers with Michael terminal acceptors are used, the compositions described herein contain a hardener selected from monomeric thiol, polythiol, polyamine and blocked polyamine.

Hardeners that can be used in the compositions described herein include compounds capable of reacting with terminal groups of a bis (sulfonyl) alkanol-containing polythioether, such as compounds capable of reacting with hydroxyl groups, alkenyl groups, epoxy groups, thiol groups, amino groups or isocyanate groups.

Examples of suitable hardeners capable of reacting with hydroxyl groups include diisocyanates and polyisocyanates, examples of which are described herein.

Examples of suitable hardeners capable of reacting with alkenyl groups include dithiols and polythiols, examples of which are described herein.

The polyalkoxysilyl terminal bis (sulfonyl) alkanol-containing polythioethers described herein can hydrolyze in the presence of water, causing self-polymerization via condensation. Catalysts for use with the polyalkoxysilyl-terminal bis (sulfonyl) alkanol-containing polythioether include titanium organic compounds such as tetraisopropoxy titanium, tetra-tert-butoxy titanium, titanium di (isopropoxy) bis (ethyl acetate, acetate) and titanium di (isopropoxy) bis (acetylacetoacetate); organic tin compounds: dibutyltin dilaurate, dibutyltin bisacetylacetoacetate and tin octylate; metal dicarboxylates, such as lead dioctylate; zirconium organic compounds such as zirconium tetraacetylacetonate; and aluminum-organic compounds such as aluminum triacetyl-acetonate. Other examples of suitable catalysts for curing in a wet environment include diisopropoxy bis (ethyl acetoacetonate) titanium, diisopropoxy bis (acetylacetonate) titanium and dibutoxy bis (methyl acetoacetonate) titanium. It should be understood that since the hardener for the polyalkoxysilyl terminal bis (sulfonyl) alkanol-containing polythioether may be atmospheric moisture, it is not necessary to include the hardener in the curable composition containing the polyalkoxysilyl terminal bis (sulfonyl) alkanol-containing polythioether. Therefore, for compositions containing a polyalkoxysilyl-terminal bis (sulfonyl) alkanol-containing polythioether, the hardener for the polyalkoxysilyl groups is atmospheric moisture.

The compositions described herein may contain from about 90% to 150% stoichiometric amount, from about 95% to 125%, and in some embodiments, from about 95% to 105% of the amount of hardener (s).

Additional sulfur-containing polymers

In some embodiments, the compositions described herein comprise, in addition to the bis (sulfonyl) alkanol-containing polythioether or prepolymer thereof, or a product of any of the reactions described herein, or a combination of any of the above, one or more additional sulfur-containing polymers. The sulfur-containing polymer may be any polymer having at least one sulfur atom in the repeating fragment, including (but not limited to) polymer thiols, polythiols, thioethers, polythioethers, sulfur-containing polyformals and polysulfides. The term “thiol,” as used herein, refers to a compound containing a thiol or mercaptan group, that is, an “SH” group, as the sole functional group or in combination with other functional groups, such as hydroxyl groups, as in the case, for example thioglycerols. Polythiol is a compound having more than one SH-group such as dithiol or thiol with greater functionality. Such groups are usually terminal and / or side, so that they contain active hydrogen, which can react with other functional groups. The polythiol may contain both terminal and / or side sulfur atoms (—SH) and non-reactive sulfur atoms (—S— or —S — S—). Thus, the term “polythiol” generally embraces polythioethers and polysulfides.

Examples of additional sulfur-containing polymers that can be used in the compositions described herein include, for example, those described in US Pat. Nos. 6,172,179, 6,509,418 and 7,009,032. In some embodiments, the compositions described herein comprise a polythioether having the structure of Formula (29):

where R ^{1 is} selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 cycloalkanalkanediyl, - [(- CH ₂ -) _s -X-] _q - (- CH ₂ -) _r - and - [( -CH ₂ -) _s -X-] _q - (- CH ₂ -) _r -, in which at least one -CH ₂ - moiety is substituted with a methyl group; R ^{2 is} selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 cycloalkanalkanediyl and - [(- CH ₂ -) _s -X-] _q - (- CH ₂ -) _r -; X is selected from O, S, and —NR ⁵ -, where R ^{5 is} selected from a hydrogen atom and methyl; m is an integer from 0 to 10; n is an integer from 1 to 60; p is an integer from 2 to 6; q is an integer from 1 to 5, and r is an integer from 2 to 10. Such polythioesters are described in US Pat. No. 6,172,179 col. 2, line 29 - count. 4, line 34.

These one or more additional sulfur-containing polymers can be difunctional or multifunctional, for example, contain 3-6 terminal groups, or be a mixture thereof.

In some embodiments, the compositions described herein comprise from about 10 weight. % to 90 weight. % described in the present text sulfur-containing polymer, from about 20 weight. % to 80 weight. %, from about 30 weight. % to 70 weight. %, and in some embodiments, the implementation of about 40 weight. % to 60 weight. %, where weight percentages are calculated relative to the total weight of all non-volatile components of the composition (i.e., dry weight).

As used herein, the term “polysulfide” means a polymer that contains one or more sulfide bridges, i.e. -S _x - bridges, where x is from 2 to 4, in the main polymer chain and / or in the lateral positions of the polymer chain. In some embodiments, the polysulfide polymer comprises two or more sulfur-sulfur bridges. Suitable polysulfides are commercially available, e.g., from Akzo Nobel and Toray Fine Chemicals under the name Thiokol-LP and Thioplast ^®. Thioplast ^® products are available in a wide range of molecular weights, for example from less than 1100 to over 8000, where the molecular weight is the average molecular weight in grams per mole. In some cases, the polysulfide has a number average molecular weight of from 1000 Da to 4000 Da. The crosslink density in these products also varies, depending on the amount of crosslinking agent used. The content of -SH, i.e. the content of thiols or mercaptans in these products may also vary. The content of mercaptans and the molecular weight of the polysulfide can affect the curing rate of the polymer, while the curing rate increases with molecular weight.

Sulfur-containing polyformal prepolymers that can be used in sealants for the aerospace industry are described, for example, in US patent application No. 2012/0234205 and in US patent application No. 2012/0238707.

In some embodiments, the sulfur-containing polymer is selected from polythioether and polysulfide, and combinations thereof. In some embodiments, the sulfur-containing polymer is a polythioether, and in some embodiments, the sulfur-containing polymer is a polysulfide. The sulfur-containing polymer may contain a mixture of different polythioesters and / or polysulfides, and polythioesters and / or polysulfides may have the same or different functionality. In some embodiments, the sulfur-containing polymer has an average functionality of from 2 to 6, from 2 to 4, from 2 to 3, and in some embodiments, from 2.05 to 2.5. For example, the sulfur-containing polymer may be selected from a difunctional sulfur-containing polymer, a trifunctional sulfur-containing polymer, and combinations thereof.

You can choose a hardener that is able to react with the terminal groups of the sulfur-containing polymer and sulfur-containing compounds. In some embodiments, the sulfur-containing polymer and the sulfur-containing compound described herein contain the same groups capable of reacting with a hardener. For example, in some embodiments, both the sulfur-containing polymer and the sulfur-containing compound described herein contain reactive thiol groups, and the hardener contains reactive alkenyl groups, epoxy groups, isocyanate groups, Michael acceptor groups, or groups containing a saturated carbon atom bearing a leaving group well suited for nucleophilic substitution, such as, for example, -Cal, -Br, -I, -OSO ₂ CH ₃ (mesylate), -OSO ₂ -C ₆ H ₄ -CH ₃ ( tosylate) etc.

In some embodiments, the copolymerizable adhesion-improving adduct described herein may be present in an amount of from 0.1 weight. % to 15 weight. % composition, less than 5 weight. %, less than 2 weight. %, and in some embodiments, less than 1 weight. %, based on the total dry weight of the composition.

The compositions described herein may include one or more catalysts. The catalyst can be selected according to the hardener chemistry used. In some embodiments, for example, during the curing of thiol-terminal bis (sulfonyl) alkanol-containing polythioethers or prepolymers and polyepoxides, the catalyst is an amine catalyst. The curing catalyst may be present in an amount of from 0.1 to 5 weight. %, based on the total weight of the composition. Examples of suitable catalysts include 1,4-diazabicyclo [2.2.2] octane (DABCO ^® , commercially available from Air Products, Chemical Additives Division, Allentown, Pa.) And DMP-30 ^® (accelerating composition comprising 2,4,6- tris (dimethylaminomethyl) phenol).

In some embodiments, the compositions described herein comprise one or more than one adhesion promoter. One or more additional adhesion promoters may be present in an amount of from 0.1 weight. % to 15 weight. % composition, less than 5 weight. %, less than 2 weight. %, and in some embodiments, less than 1 weight. %, based on the total dry weight of the composition. Examples of adhesion promoters include phenolics such as Methylon ^® phenolic resins, and organosilanes such as epoxy, mercapto or amino functional silanes such as Silquest ^® A-187 and Silquest ^® A-1100. Other suitable adhesion promoters are known in the prior art.

In some embodiments, the composition described herein contains an ethylenically unsaturated silane, such as, for example, a sulfur-containing ethylene unsaturated silane, which can improve the adhesion of the hardened sealant to a metal surface. As used herein, the term “ethylene-type ethylene unsaturated silane” means a molecular compound that contains at least one sulfur atom (S) in the composition of the molecule (i), (ii) at least one, in some cases at least two ethylenically unsaturated carbon-carbon bonds, such as carbon-carbon double bonds (C = C); and (iii) at least one silane group, —Si (—R) _m (—OR) _3-m , where each R is independently selected from a hydrogen atom, alkyl, cycloalkyl, aryl, and others, and m is selected from 0, 1 and 2. Examples of ethylenically unsaturated silanes are described in US patent application No. 2012/0040104, which is incorporated herein by reference in its entirety.

In some embodiments, the compositions described herein can be cured using actinic radiation. Examples of compositions comprising actinic radiation curable polythioether compositions are described in US patent application No. 2012/0040104. Such compositions may include, in addition to the adhesion improver described herein, one or more sulfur-containing polymers, such as thiol-terminal sulfur-containing polymers, a polyene, such as polyvinyl ether, including, for example, polyvinyl ether of Formula (27).

In some embodiments, the compositions described herein comprise one or more hardeners, such as an epoxy compound, isocyanate, and a combination thereof.

The compositions described herein may contain one or more catalysts.

The compositions described herein may contain one or more different types of excipients. Suitable fillers include those well known in the art, including inorganic fillers such as carbon black and calcium carbonate (CaCO ₃ ), silica gel, polymer powders, and lightweight fillers. Suitable light fillers include, for example, those described in US Pat. No. 6,525,168. In some embodiments, the composition comprises from 5 wt.% To 60 wt.% Filler or a combination of fillers, from 10 wt.% To 50 wt.%, And in some embodiments, from 20 wt.% To 40 wt.% Based on total dry weight of the composition. The compositions described herein may further comprise one or more colorants, thixotropic agents, accelerators, flame retardants, adhesion promoters, solvents, masking agents, or a combination of any of the above. It is clear that the fillers and additives used in the composition are selected so that they are compatible with each other, as well as with the polymer component, hardener and / or catalyst.

In some embodiments, the compositions described herein comprise low density filler particles. When used in the present text, the term "low density" in relation to such particles means that the particles have a specific gravity of not more than 0.7, in some embodiments, not more than 0.25, and in some embodiments, not more than 0.1. Suitable low density filler particles often fall into two categories - microspheres and amorphous particles. The specific gravity of the microspheres can be from 0.1 to 0.7, and they include, for example, polystyrene foam, microspheres of polyacrylates and polyolefins, and silica gel microspheres having a particle size in the range of 5 to 100 microns and a specific gravity of 0.25 (Eccospheres ^® ). Other examples include microspheres alumina / silica having a particle size ranging from 5 to 300 microns and a specific gravity of 0,7 (Fillite ^®), aluminum silicate microspheres having a specific gravity of about 0.45 to 0,7 (Z-Light ^® ), microspheres of a calcium carbonate-coated polyvinylidene copolymer having a specific gravity of 0.13 (Dualite ^® 6001AE), and microspheres of a calcium carbonate-coated acrylonitrile copolymer, such as Dualite ^® E135, having an average particle size of about 40 μm and a density of 0.135 g / cm ³ (Henkel). Suitable excipients for lowering the specific gravity of the composition include, for example, hollow microspheres such as Expancel ^® microspheres (available from AkzoNobel) or Dualite ^® microspheres of low density polymer (available from Henkel). In some embodiments, the compositions described herein comprise low density filler particles having a thin coating on the outer surface, such as those described in US Patent Application No. 2010/0041839 in paragraphs [0016] to [0052], the cited fragment of which is incorporated into this text by reference.

In some embodiments, the low density filler is less than 2 weight. % composition, less than 1.5 weight. %, less than 1.0 weight. %, less than 0.8 weight. %, less than 0.75 weight. %, less than 0.7 weight. %, and in some embodiments, less than 0.5 weight. % of the composition, where the weight percent is calculated relative to the total dry weight of the composition.

In some embodiments, the compositions described herein comprise at least one filler that effectively reduces the specific gravity of the composition. In some embodiments, the specific gravity of the composition is from 0.8 to 1, from 0.7 to 0.9, from 0.75 to 0.85, and in some embodiments, is 0.8. In some embodiments, the specific gravity of the composition is less than about 0.9, less than about 0.8, less than about 0.75, less than about 0.7, less than about 0.65, less than about 0.6, and in some embodiments, less than about 0.55.

In some embodiments, a thiol-terminal sulfur-containing polymer comprising a combination of thiol-terminal sulfur-containing polymers is from about 50 weight. % to 90 weight. % of the composition, from about 60 weight. % to 90 weight. %, approximately plumb. % to 90 weight. %, and in some embodiments, the implementation of about 80 weight. % to 90 weight. % of the composition, where the weight percent is calculated relative to the total dry weight of the composition.

In some embodiments, a thiol-terminal polythioether comprising a combination of thiol-terminal polythioesters is from about 50 weight. % to 90 weight. % of the composition, from about 60 weight. % to 90 weight. %, from about 70 weight. % to 90 weight. %, and in some embodiments, the implementation of about 80 weight. % to 90 weight. % of the composition, where the weight percent is calculated relative to the total dry weight of the composition.

The composition may also contain, if desired, any number of additives. Examples of suitable additives include plasticizers, pigments, surfactants, adhesion promoters, thixotropic agents, flame retardants, masking agents and accelerators (such as amines, including 1,4-diaza-bicyclo [2.2.2] octane, DABCO®), and combinations of any of these components. If used, additives may be present in the composition in an amount of, for example, from about 0% to 60% by weight. In some embodiments, the additives may be present in the composition in an amount of about 25% to about 60% by weight.

Application

The compositions described herein can be used, for example, in sealants, coatings, encapsulating compositions and sealing compositions. Sealants include compositions that can provide a film that can withstand working conditions such as humidity and temperature, and at least partially block the penetration of substances such as water, fuel, and other liquids and gases. The coating composition is a coating applied to the surface of the substrate, for example to improve the characteristics of the substrate, such as appearance, adhesion, wettability, corrosion resistance, wear resistance, fuel resistance and / or abrasion resistance. The sealing composition includes material that can be used in electronic components to provide resistance to shock and vibration and to eliminate the effects of moisture and corrosive agents. In some embodiments, the sealant compositions described herein can be used, for example, as sealants for the aerospace industry and as an internal coating for fuel tanks.

In some embodiments, compositions, such as sealants, may be produced as multicomponent compositions, such as bicomponent compositions, wherein one component contains one or more thiol-terminal polythioethers described herein and the second component contains one or more polyfunctional sulfur-containing epoxides, described in this text. Additives and / or other compounds can be added to any of the components as desired and necessary. These two separate components can be combined and mixed before use. In some embodiments, the life time of one or more mixed thiol terminal polythioethers and epoxides is at least 30 minutes, at least 1 hour, at least 2 hours, and in some embodiments, more than 2 hours, where the life time is called the time period during which the mixed composition remains acceptable for use as a sealant after mixing.

Compositions, including sealants described herein, can be applied to any variety of substrates. Examples of substrates on which the composition can be applied include metals such as titanium, stainless steel and aluminum, any of which can be anodized, primed, organic coated or chromated; epoxy compounds; urethanes; graphite; fiberglass composites; Kevlar ^® ; acrylic compounds and polycarbonates. In some embodiments, the compositions described herein can be coated on a substrate, such as a polyurethane coating.

The compositions described herein can be applied directly to the surface of a substrate or over a primer layer by any suitable coating methods known to those skilled in the art.

In addition, methods for sealing holes using the composition described in this text are described. Such methods include, for example, applying the composition described herein to a surface to seal a hole and curing the composition. In some embodiments, methods for sealing apertures include applying the sealant composition described herein to the surface of the hole and curing the sealant to form a sealed hole.

In some embodiments, the composition can be cured under ambient conditions, where ambient conditions mean a temperature of from 20 ° C to 25 ° C and atmospheric humidity. In some embodiments, the composition can be cured under conditions ranging from 0 ° C to 100 ° C and humidity from 0% RH to 100% RH. In some embodiments, the composition can be cured at a higher temperature, such as at least 30 ° C, at least 40 ° C, and in some embodiments, at least 50 ° C. In some embodiments, the composition can be cured at room temperature, for example 25 ° C. In some embodiments, the composition can be cured by exposure to actinic radiation, such as ultraviolet radiation. As will be understood, these methods can be used to seal openings in aerospace ships, including aircraft and spacecraft.

In some embodiments, the composition reaches non-sticky hardness in less than about 2 hours, less than about 4 hours, less than about 6 hours, less than about 8 hours, and in some embodiments, less than about 10 hours, with temperatures below about 200 ° F.

The formation time of a complete tight seal using the curable composition of the present invention may depend on several factors, as will be appreciated by those skilled in the art, and as required by accepted standards and specifications. In general, the curable compositions of the present invention achieve adhesion forces in 24-30 hours, and 90% of the total adhesion forces are achieved within 2-3 days after mixing and application to the surface. In General, the full adhesion force, as well as other properties of the cured composition of the present invention, are fully achieved within 7 days after mixing and applying the cured composition to the surface.

The hardened compositions described herein, such as cured sealants, exhibit properties suitable for use in the aerospace field. In general, it is desirable that sealants used in the aviation and aerospace industries have the following properties: peel strength of more than 20 psi (32 psi) on Aerospace Material Specification (AMS) substrates, as defined in dry conditions, after being placed in JRF Type I for 7 days and then immersed in a 3% NaCl solution, according to the specifications of the AMS 3265 B test; tensile strength between 300 pounds per square inch (psi) and 400 psi; peel strength greater than 50 pounds per linear inch (lb / ln.inch); elongation from 250% to 300%; and stiffness greater than 40 according to Durometer A. These and other properties of a cured sealant suitable for use in aviation and aerospace are described in AMS 3265 B, which is incorporated herein by reference in its entirety. It is also desirable that after curing, the compositions of the present invention used in the field of aviation have a percent swelling volume of not more than 25% after immersion for one week at 60 ° C (140 ° F) and atmospheric pressure in JRF Type I. Other properties, ranges and / or the parameters may be similar to other sealants.

Therefore, in some embodiments, the compositions described herein are fuel resistant. As used herein, the term "fuel resistance" means that the composition, when applied to a substrate and hardened, is capable of producing a hardened product, such as a sealant, having a swelling percentage of not more than 40%, in some cases not more than 25%, in some cases not more than 20%, in other cases not more than 10%, after immersion for 1 week at 140 ° F (60 ° C) and ambient air pressure in a Reference Jet Fuel (JRF) Type I in accordance with methods similar to those described in ASTM D792 (American Society for Testing and Motherhood lamas) or AMS 3269 (Aerospace Materials Specification). The JRF Type I Reference Jet Fuel used to determine fuel resistance has the following composition: toluene: 28% ± 1% by volume; cyclohexane (technical): 34% ± 1% by volume; isooctane: 38% ± 1% by volume; and tert-dibutyl disulfide: 1% ± 0.005%) by volume (see AMS 2629, July 1, 1989, §3,1,1, etc., available from SAE (Society of Automotive Engineers)).

In some embodiments, the compositions described herein provide a hardened product, such as a sealant, providing an elongation of at least 100% elongation and a tensile strength of at least 400 psi, when measured in accordance with the procedure described in AMS 3279, §3.3.17.1, test method AS5127 / 1, §7.7.

In some embodiments, the compositions provide a hardened product, such as a sealant, that provides shear lap strength greater than 200 psi, for example at least 220 psi, at least 250 psi, and , in some cases, at least 400 psi, when measured in accordance with the procedure described in SAE AS5127 / 1 paragraph 7.8.

In some embodiments, the hardened sealant containing the composition described herein meets or exceeds aerospace sealant requirements in AMS 3277.

Also described are openings, including openings in aerospace ships, sealed by the compositions described herein.

In some embodiments, the cured sealant described herein has the following characteristics after curing for 2 days at room temperature, 1 day at 140 ° F, and 1 day at 200 ° F: dry hardness 49, tensile strength 428 psi and 266% elongation; and after 7 days in JRF Type I, hardness 36, tensile strength 312 psi, and elongation 247%.

In some embodiments, the compositions described herein have Shore hardness (after 7 days of solidification) greater than 10, greater than 20, greater than 30, and in some embodiments greater than 40; tensile strength greater than 10 psi, more than 100 psi, more than 200 psi, and in some embodiments, greater than 500 psi; elongation greater than 100%, greater than 200%, greater than 500%, and in some embodiments, greater than 1000%; and swelling after treatment in JRF Type I (7 days) is less than 20%.

Examples

The embodiments described herein are further illustrated by the examples described below, which describe the synthesis, properties and application of some adhesion-improving adducts and compositions containing adhesion-improving adducts. It will be apparent to those skilled in the art that many modifications may occur, both in terms of materials and methods, without departing from the scope of the present invention. In the examples described below, Permapol® P3.1E is a thiol terminal polymer, and the S-5304 accelerator is an epoxy compound, both of which are commercially available from PRC-DeSoto, International, Inc., Sylmar, CA. DABCO® 33-LV is an amine catalyst commercially available from Air Products and Chemicals, Inc.

Example 1

Adhesion Improving Adduct Silquest® A-1120 and 2- (Methacryloyloxy) Ethyl Acetoacetate (2-MEAA)

Silquest® A-1120 (1 mol, 222.36 g) and ethanol were charged into a 50 ml 3-necked round bottom flask. The flask was purged with nitrogen and equipped with a dropping funnel and a temperature sensor. 2- (Methacryloyloxy) ethyl acetoacetate (2-MEAA, 1 mol, 214.11 g) and ethanol were charged into a 50 ml dropping funnel. 1,8-diazabicycloundec-7-ene (DBU) (0.027 g; 1 drop from a standard plastic pipette) was added to silane. The 2-MEAA solution was added dropwise over 2.75 hours, and the resulting mixture was stirred for 3 days. The resulting product was used as a 50% solution in ethanol. This reaction is shown in FIG. one.

Got a sealant (Sealant 1) having the composition shown in table 1.

Permapol® P3.1E and the aminosilane adhesion improver (0.4 g of a 50% solution) were weighed into the mixing chamber and mixed in a Hauschild mixer for 30 seconds. CaCO ₃ was added and mixed for 30 seconds. The contents were manually mixed and then mixed again in a Hauschild mixer for 30 seconds. Accelerator S-5304 was added, mixed manually and then mixed again in a Hauschild mixer for 30 seconds. DABCO® 33-LV catalyst (3 drops from a plastic pipette) was added and the contents were mixed. The hardened sealant (24 hours at 140 ° F) had a hardness of 35 (Shore), and the percentage of failure of the surfaces in contact is shown in Table 2.

Example 2

Adhesion Improving Adduct Silquest® A-1120 and Benzoquinone (BQ)

Benzoquinone (6.49 g) and ethanol (150 g) were charged into a 250 ml Erlenmeyer flask. With stirring, the contents were heated to dissolve the benzoquinone. After cooling to room temperature, Silquest® A-1120 (13.34 g) and ethanol (20 g) were loaded into a 500 ml 3-necked round bottom flask, the contents were purged with nitrogen; and Polycat® DBU (amine catalyst, ~ 0.081 g; 3 drops from a narrow-nose pipette) was added. The mixture was allowed to react for 4 hours at room temperature with stirring. The product was obtained as 13.7 weight. % solution in ethanol. The reaction is depicted in FIG. 2.

Got the first sealant (Sealant 1) having the composition shown in table 3.

The Permapol® 3.1E prepolymer and amino-hydroquinone adhesion-improving adduct (1.46 g ~ 14% solution) were weighed into the mixer chamber and mixed in a Hauschild mixer for 30 seconds. CaCO ₃ was added and mixed manually and in a Hauschild mixer. Accelerator S-5304 was added and mixed. DABCO® 33-LV catalyst (3 drops from a plastic pipette) was added and mixed.

Got a second sealant (Sealant 2) having the composition shown in table 4.

Permapol® P3.1E polymer, the adduct from Example 1 (0.4 g of a 50% solution) and the adduct from Example 2 (1.46 g of a ~ 14% solution) were weighed into the mixer chamber, manually mixed and mixed in Hauschild mixer for 30 seconds. Subsequently, CaCO ₃ , S-5304 accelerator and DABCO® 33-LV catalyst (3 drops from a standard plastic pipette) were added and mixed.

The failure rate of the contact surfaces for two hardened sealant compositions (24 hours at 140 ° F) on several surfaces is shown in Table 5. The Shore hardness of the hardened sealants was 39 and 25, respectively.

Example 3

Silquest® A-189 adduct and 1,3-bis (vinylsulfonyl) -2-propanol

Silquest® A-189 and 1,3-bis (vinylsulfonyl) -2-propanol were reacted in the presence of DBU to give an appropriate adhesion-improving adduct. Got a sealant having the composition shown in table 6.

The adhesive samples were cured for 5 days at room temperature, then cured for 27 hours at 140 ° F. The percentage of destruction in contact surfaces for hardened sealant samples is shown in table 7.

Comparative Example 1

Permapol® P3.1E polymer (10 g, thiol terminal polymer, commercially available from PRC-DeSoto International, Sylmar, California) and calcium carbonate (5.0 g) were mixed in a Hauschild mixer for 30 seconds at 2300 rpm. The S-5304 accelerator (2.6 g, epoxy paste, commercially available from PRC-DeSoto International, Sylmar, California) and a triethylenediamine catalyst (0.08 g) were successively added and mixed. Samples were applied to various substrates and cured at room temperature for 24 hours, then 48 hours at 140 ° F. The percentage of destruction of the surfaces in contact was measured by peeling the sample from the substrates. The results obtained are shown in table 8.

Example 4

Density functional theory calculations

Gibbs free energy for the interaction of various functional groups with an Al ₄ O ₆ cluster (Li et al., "Structural determination of (Al ₂ O ₃ ) _n (n = 1-7) clusters based on density functional calculation," Computational and Theoretical Chemistry 2012, 996, 125-131), representing the surface of alumina of a representative aerospace substrate, was calculated using methods based on the Density Functional Theory (DFT). All structures were optimized using Gaussian 09 / B3LYP / 6-31g (d), and the vibrational frequency was calculated at the same level of theory to confirm that all structures are at a local minimum. A one-point energy calculation was used with the CPCM solvation scheme to calculate energy in the aquatic environment. Gibbs free energy for interaction was calculated under standard pressure and temperature conditions (1 atm and 25 ° C) without correction.

Various functional groups were analyzed for their intrinsic properties, including the HOMO energy (higher occupied molecular orbital), LUMO (lowest vacant molecular orbital), and the energy difference between the HOMO and LUMO. Typically, functional groups with a higher HOMO energy are more electron-donating, and groups with a lower LUMO energy are more electron-accepting. Comparing the various functional groups in Table 9, 3-hydroxy-1,2-dimethylpyridin-4 (1H) -one (HOPO) has the highest HOMO energy, indicating that HOPO is the most electron-donating group. The bis (sulfonyl) -2-propanol (BSP) functional group, on the other hand, has the lowest HOMO energy, indicating that it is the least electron-donating group.

The interactions between the various functional groups and the alumina cluster were calculated. The Gibbs free energy for interaction in the gas phase (ΔG _g ) and in water (ΔG _w ) was calculated, and the results are shown in FIG. 3, together with the contribution of the enthalpy (ΔH) of the reaction. In FIG. 3, a more negative ΔG value corresponds to a more stable complex and a stronger interaction between the functional group and alumina. BSP and NORO have a stronger interaction than acetoacetate with alumina in the gas phase and in a simulated aqueous environment. Acetoacetate binds to Al ₄ O ₆ by coordinating electron-enriched carbonyl oxygen (in acetoacetate) with electron-deficient aluminum (in Al ₄ O ₆ ). NORO interacts with Al ₄ O ₆ as a bidentate ligand: i.e. carbonyl oxygen (in HOPO) binds to aluminum (in Al ₄ O ₆ ), and the hydroxyl group (in HOPO) is hydrogen bonded to oxygen (in Al ₄ O ₆ ). The tridentate binding of BSP to Al ₄ O ₆ was revealed: two sulfonyl groups (in BSP) bind to two aluminum atoms (in Al ₄ O ₆ ) in addition to the hydrogen bond between the hydroxyl group (in BSP) and the oxygen atom (in Al ₄ O ₆ ). Even though the BSP is not very electron-donating (as illustrated by the low energy of the HOMO in Table 9), nevertheless, strong binding to Al ₄ O ₆ is observed at three coordination sites.

In conclusion, it was shown that the BSP functional group binds to alumina by the type of tridentate ligand, which leads to a very strong interaction (adhesion). Unlike other highly binding ligands, such as NORO, BSP is heavily oxidized and is expected to be highly stable. Structures with a binding type similar to BSP can also give strong binding to alumina.

Similar methods can be used to identify other metal-coordinated ligands that are suitable for enhancing adhesion to the surface of a particular metal and can be incorporated into the prepolymer backbone and / or act as a terminal group of the prepolymer as described herein.

In conclusion, it should be noted that there are alternative methods for the practical implementation of the embodiments described herein. Accordingly, the described embodiments are to be regarded as illustrative and non-limiting. In addition, the claims are not limited to the details described in the text, but cover their entire volume, as well as the volume of their equivalents.

Claims (81)

1. Improving adhesion adduct having the structure of Formula (13):

where R ¹¹ contains an adhesion improving group; P contains the core of the adhesion promoter; M contains a ligand capable of coordinating with the metal; R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ −P − R ¹² and the metal chelating agent R ¹³ −M − R ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ^{14 is} selected from a non-reactive group, a reactive functional group or is absent, where an adhesion improving group includes polyalkoxysilyl, phosphonate, amine, carboxylic acid and / or phosphonic acid; and A ligand capable of coordinating with a metal contains a structure selected from Formula (12a), Formula (12b), Formula (12c), Formula (12d), Formula (12e), and combinations of any of the following:

where each X is independently selected from –C (O) - and –S (O) ₂ -; n is an integer from 1 to 3; and R ⁵ represents C _1-4 alkanediyl; or selected from 2,3-dihydroxybenzoic acid, 5-nitrosalicylate, 3-hydroxy-4-pyridinone, 3-hydroxy-2-pyridinone, 2-2'-dihydroxyazobenzene, 8-hydroxyquinoline, oxalate, malonate, citrate, iminodiacetic acid, picolinic acid acids, maltol, kojic acid, N, N'-diacetic acid (EDTA), N- (2-hydroxy) ethylenediamine triacetic acid (HEDTA), ethylenediamine-N, N'-bis (2-hydroxyphenylacetic acid (EDDHA), and N , N'-bis (hydroxybenzyl) ethylenediamine-N, N'-diacetic acid (HBED), acetoacetate, quinone and a combination of any of the following; or selected from H ₂ O ₂ , acetoacetonate (CH ₂ (COCH ₃ ) ₂ ), EDTA, trans-1,2-cyclohexanediamine tetraacetic acid, glycol ether diamine tetraacetic acid (GEDTA, (CH ₂ OCH ₂ CH ₂ N (CH ₂ COOH) ₂ ) ₂ ), diethylenetriamine pentaacetic acid (DTPA, HOOCH ₂ N (CH ₂ CH ₂ N (CH ₂ COOH) ₂ ) ₂ ), nitrile triacetic acid (NTA, N (CH ₂ COOH) ₃ ), salicylic acid, lactic acid, acetoacetonate, triethanolamine and combinations of any of the above. 2. Adhesion improving adduct according to claim 1, including the structure of Formula (16a), the structure of Formula (16b), or a combination thereof:

where each R ^{16 is} independently selected from C _1-3 alkyl. 3. Improving the adhesion of the adduct according to claim 1, having the structure of Formula (15):

where each R ^{16 is} independently selected from C _1-3 alkyl. 4. Improving the adhesion of the adduct according to claim 1, containing the reaction product of reagents, including: adhesion promoter of Formula R ¹¹ −P − R ¹² ; and metal chelating agent of Formula R ¹³ −M − R ¹⁴ . 5. The adhesion improving adduct according to claim 1, wherein P contains a reactive functional group, R ¹⁴ contains a reactive functional group, or both P and R ¹⁴ contain a reactive functional group. 6. Improving the adhesion of the adduct according to claim 1, containing the reaction products of reagents, including: the adhesion improving adduct according to claim 1, comprising a first reactive functional group; and a compound having a second reactive functional group capable of reacting with the first reactive functional group. 7. Improving the adhesion adduct according to claim 6, where the specified compound includes a polyamine or polythiol. 8. Improving the adhesion adduct according to claim 1, comprising a multivalent adhesion-improving adduct having the structure of Formula (18):

where R ¹¹ contains an adhesion improving group; P contains a core adhesion promoter; M contains a ligand capable of coordinating with the metal; R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ −P − R ¹² and the metal chelating agent R ¹³ −M − R ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ contains a reactive functional group, R ^{14 '} is a fragment formed by the reaction of R ¹⁴ and V; B is the core of the z-valent polyfunctionalizing agent B (-V) _z , where z is an integer from 3 to 6; and each -V is a group containing a group capable of reacting with R ¹⁴ ; and each -V'- is formed by the reaction of -V with R ¹⁴ . 9. Improving the adhesion adduct according to claim 1, which is a copolymerizable improving adhesion adduct having the structure of Formula (21):

where R ¹¹ contains an adhesion improving group; P contains a core adhesion promoter; M contains a ligand capable of coordinating with the metal; R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ −P − R ¹² and the metal chelating agent R ¹³ −M − R ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ contains a reactive functional group; B is the core of a z-valent polyfunctionalizing agent of Formula (22):

where z is an integer from 3 to 6; z1 is an integer from 1 to z-1; each —V ¹ is a group containing a first reactive functional group; and at least one —V ² contains a second reactive functional group; and each R ^{14 '} represents a fragment formed by the reaction of R ¹⁴ and -V ¹ ; and each —V ^{1 ′} is a fragment formed by the reaction of —V ¹ with R ¹⁴ . 10. Improving the adhesion of the adduct according to claim 1, including copolymerizable sulfur-containing improving adhesion adduct of the Formula (23):

where each R ^{1 is} independently selected from C _2-6 alkanediyl, C _6-8 cycloalkanediyl, C _6-10 alkanocycloalkanediyl, C _5-8 heterocycloalkanediyl and - [- (CHR ³ ) _s -X-] _q - (CHR ³ ) _r -; where each R ³ independently selected from a hydrogen atom and methyl; each X is independently selected from —O—, —S— and —NR—, where R is selected from a hydrogen atom and methyl; s is an integer from 2 to 6; q is an integer from 1 to 5; and r is an integer from 2 to 10; R ¹¹ contains an adhesion improving group; P contains a core adhesion promoter; M contains a ligand capable of coordinating with the metal; R ^{12 '} and R ^13' are fragments formed by the reaction of R ¹² and R ^{13 of the} adhesion promoter R ¹¹ −P − R ¹² and the metal chelating agent R ¹³ −M − R ¹⁴ , where R ¹² and R ¹³ include mutually reactive functional groups, and R ¹⁴ contains a reactive functional group. R ^{14 '} is a fragment formed by the reaction of R ¹⁴ and a thiol group; B is the core of the z-valent polyfunctionalizing agent B (-V) _z , where z is an integer from 3 to 6; z1 is an integer from 1 to z-1; and each -V is a group containing a group capable of reacting with a thiol group; and each -V'- is formed by the reaction of -V with a thiol group. 11. A composition comprising an adhesion improving adduct according to claim 1. 12. The composition according to p. 11, containing a sulfur-containing prepolymer. 13. The composition of claim 12, wherein the sulfur-containing prepolymer comprises a thiol-terminal sulfur-containing prepolymer selected from a thiol-terminal polythioether prepolymer, a thiol-terminal polysulfide prepolymer, a thiol-terminal sulfur-containing polyformal prepolymer, and a combination of any of the above. 14. The composition of claim 13, wherein the sulfur-containing prepolymer comprises a thiol-terminal polythioether prepolymer. 15. A sealant composition containing the composition of claim 11, optionally cured to form a cured sealant.

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