High performance silicone-epoxy compositions

Abstract

The present invention is directed to a two-component (2K) composition based on modified epoxy resins. More specifically, the present invention is directed to a two-component (2K) composition comprising, as a first component, a silicone-based resin containing epoxy functional groups, and, as a second component, a curing agent comprising at least one alkoxy-containing amino-functional silicone resin: the reaction of the two components of the composition gives a cured product that exhibits wear and corrosion resistance.

Description

[Technical field]

[0001] The present invention relates to a two-component (2K) composition based on modified epoxy resins. More specifically, the present invention relates to a two-component (2K) composition comprising as a first component a silicone-based resin containing epoxy functional groups and as a second component a curing agent comprising at least one alkoxy-containing amino-functional silicone resin: the reaction of the two components of the composition gives a cured product that exhibits abrasion and corrosion resistance. [Background technology]

[0002] Epoxy resins have found a wide range of uses based primarily on the ability to tailor the properties of the cured epoxy resin to achieve specific performance characteristics through the specific selection of resin and crosslinker (or hardener).

[0003] Recognized for their versatility, properly cured epoxy resins also offer several other advantages, including: excellent chemical resistance, especially to alkaline environments; high tensile and compressive strength; high fatigue strength; low shrinkage upon cure; and electrical insulating properties and their retention upon aging or environmental exposure. However, as identified by Sadeddin et al., 32nd Power Systems Conference (2017), cured epoxy resin systems can also exhibit adverse characteristics such as low fracture resistance and impact strength, low thermal stability, poor pigment retention, poor flexibility, and poor hydrophobicity.

[0004] To mitigate these negative properties, some authors have proposed adding modifiers such as rubbers or silicones to epoxy resins. By way of example, see in this regard Ualeto et al., Developments in Smart Anticorrosive Coatings with Multifunctional Characteristics, Progress in Organic Coatings, Vol. 111, 294-314 (2017); and Giaveri et al., Polysiloxane-Epoxy Resin for High Temperature Coatings: Structural Effect on Layer Performance after 450°C Treatment, https: / / doi.org / 10.3390 / coatings7120213, where the interpenetrating polymer network (IPN) of the binder is formed simultaneously with the polymerization of the silicone and epoxide prepolymers.

[0005] The incorporation of siloxanes as modifiers into epoxy resin-based compositions tends to be done by physical blending, but such blending can promote a deleterious increase in the viscosity of the system and even phase separation and bleeding of the siloxane components from the so-called blended system. Furthermore, when these blended systems are cured under a catalyst, the high cure speed not only prevents proper leveling in certain coating, adhesive, or sealant applications, but also limits material bleeding: moisture can be trapped under the surface of the coating during curing and evaporate from the adhesive or sealant composition, causing bubbling and buckling in the cured composition, or at least nanoscale material failure. Of course, material failure begins at the nanoscale and then expands to the microscale and then to the macroscale: exposure to abrasive conditions can accelerate this sequence.

[0006] An additional problem with curable blend systems is that catalysis can promote gelation of the cured composition, restricting the molecular motion of the reactant (macro)monomers, thereby delaying the proper development of desired physical properties. To avoid such gelation, as well as overplasticization of the cured composition, the macromonomer blend ratio, resin to hardener ratio, and catalyst used must be tightly controlled. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Ualeto et al., Developments in Smart Anticorrosive Coatings with Multifunctional Characteristics, Progress in Organic Coatings, Vol. 111, 294-314 (2017) [Non-Patent Document 2] Giaveri et al., Polysiloxane-Epoxy Resin for High Temperature Coatings: Structural Effects on Layer Performance after 450°C Treatment, https: / / doi.org / 10.3390 / coatings7120213 Summary of the Invention [Problem to be solved by the invention]

[0008] The present inventors have recognized a need to develop a silicone modified epoxy resin based curable composition that is stable during storage and capable of achieving complete cure without compromising the physical properties of the cured product. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Summary of the Invention According to a first aspect of the present invention, there is provided a two-component (2K) composition comprising: (A) a first component comprising: a) at least one silicone-based resin containing epoxy functional groups, and b) optionally, at least one elastomer-modified epoxy resin; The first component contains; (B) a second component comprising: c) a curing agent comprising at least one compound having at least two epoxide reactive groups per molecule, the curing agent being characterized in that it comprises at least one alkoxy-containing amino-functional silicone resin. The second component contains wherein said composition is catalyst-free and characterized in that the molar ratio of epoxide-reactive groups:epoxide groups provided by said curing agent c) is from 1.5:1 to 1:1.5, preferably from 1.1:1 to 1:1.1, more preferably 1:1.

[0010] In many embodiments, the two-component (2K) composition comprises: A) Based on the weight of the first component, the following: 10 to 60% by weight of a) said at least one silicone epoxy resin; 1 to 40% by weight of b) at least one elastomer-modified epoxy resin b); The first component contains B) a second component comprising, preferably consisting of: c) a curing agent consisting of at least one compound having at least two epoxide reactive groups per molecule, characterized in that the curing agent comprises at least one alkoxy-containing amino-functional silicone resin. wherein said composition is catalyst-free and characterized in that the molar ratio of epoxide-reactive groups:epoxide groups provided by said curing agent c) is from 1.5:1 to 1:1.5, preferably from 1.1:1 to 1:1.1, more preferably 1:1.

[0011] The silicone resin containing an epoxy functional group preferably has an epoxy equivalent in the range of 100 to 1500 g / eq, preferably in the range of 200 to 1000 g / eq, and more preferably in the range of 300 to 700 g / eq.

[0012] The elastomer-modified epoxy resin b) preferably has an epoxide equivalent weight of 200 to 2500 g / eq, for example 200 to 500 g / eq. Independently or in addition to the quantitative characteristics, the at least one elastomer-functionalized epoxy resin b) should desirably comprise or consist of at least one dimer acid-modified epoxy resin. In particular, good results have been achieved when the at least one dimer acid-modified epoxy resin is obtained as the product of a catalytic addition reaction between an epoxide compound and a C36-C44 aliphatic diacid.

[0013] The curing agent c) is at least one alkoxy-containing amino-functional silicone resin (C) having at least two amine hydrogen atoms per molecule, an amine hydrogen equivalent weight of 100 to 1500 g / eq., and a total alkoxy content (AC) of 10 to 40 mole percent based on the number of moles of silicon. 1 ), and the resin (C 1 ) includes the following units: [ka] Where: Each R is independently C 1- C 18 Alkyl group, C 6- C 18 An aryl group, or a group of the formula -R 2 NHR 3 or -R 2 NHR 2 NHR 3 and each R is selected from an amino-functional hydrocarbon group having the formula: 2 is independently 2- C 20 is an alkylene group, R 3 is C 1-is a C6 alkyl group; a, b, c, and d each define the mole fraction of each of the units (i) to (iv) such that a+b+c+d=1; and w, x, y, and z define the mole fraction of alkoxy groups such that 0≦w<1, 0≦x<2, 0≦y<3, and 0≦z<4.

[0014] The alkoxy-containing amino-functional silicone resin (C 1 ), each R independently represents C 1- C6 alkyl group, C 6- C 18 An aryl group, or a group of the formula -R 1 NHR 2 or -R 1 NHR 1 NHR 2 wherein each R 1 is independently C 2- C8 alkylene group, R 2 is C 1- C2 alkyl group. In addition, alkoxy-containing amino-functional silicone resins (C 1 Good results were obtained when R had both methyl and phenyl substitutions.

[0015] Without being bound by theory, the compositions of the present invention cure in the absence of a catalyst by a dual cure mechanism: reaction of the amine hydrogen atom of the alkoxy-containing amino-functional silicone resin curing agent with the epoxide group; and self-condensation of the reactive alkoxy group of the curing agent compound. This cure mechanism has been found to be effective under ambient conditions, resulting in a highly crosslinked system. Moreover, despite the absence of a catalyst, the open time of the composition is not considered to be detrimental.

[0016] According to a second aspect of the present invention there is provided a cured product obtainable from a two-component (2K) composition as defined above and in the accompanying claims. The present invention further relates to said cured reaction product as a coating, sealant or adhesive.

[0017] definition As used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0018] As used herein, the terms "comprising," "comprises," and "comprised of" are synonymous with "including," "includes," "containing," or "contains," and are inclusive or open-ended and do not exclude additional, unrecited members, elements, or method steps. When used, the term "consisting of" is closed and excludes all additional elements. Further, the term "consisting essentially of" excludes additional significant elements, but allows for the inclusion of non-significant elements that do not materially alter the nature of the invention.

[0019] When amounts, concentrations, dimensions, and other parameters are expressed as ranges, preferred ranges, upper values, lower values, or preferred upper and lower values, any range obtained by combining any upper value or preferred value with any lower value or preferred value is also to be understood as specifically disclosed, whether or not the resulting range is expressly referred to in the text.

[0020] The terms "preferred," "preferably," "desirably," "particularly," and their equivalents are often used herein to describe embodiments of the present disclosure that may provide particular advantages, in particular circumstances. However, the recitation of one or more preferred, preferable, desirable, or particular aspects does not imply that other aspects are not useful, and is not intended to exclude such other aspects from the scope of the present disclosure.

[0021] As used throughout this application, the word "may" is used in a permissive, or potential, sense, rather than a mandatory sense.

[0022] As used herein, room temperature is 23° C. plus or minus 2° C. As used herein, "ambient conditions" refers to the temperature and pressure of the environment in which the composition is placed, or in which the coating layer or substrate for said coating layer is placed.

[0023] The term "eq." as used herein, as is usual in chemical notation, relates to the relative number of reactive groups present in a reaction.

[0024] The term "equivalent weight" as used herein refers to the molecular weight divided by the number of functional groups involved. Thus, "epoxy equivalent weight" (EEW) means the weight (in grams) of a resin containing one equivalent of epoxy, and similarly, "amine hydrogen equivalent weight" (AHEW) is the weight (in grams) of an organic amine containing one amine hydrogen.

[0025] As used herein, the term "(co)polymer" includes homopolymers, copolymers, block copolymers, and terpolymers.

[0026] The term "epoxide" as used herein refers to a compound characterized by the presence of at least one cyclic ether group, i.e., an ether oxygen atom is bonded to two adjacent carbon atoms, thereby forming a ring structure. The term is intended to encompass monoepoxide compounds, polyepoxide compounds (having two or more epoxide groups), and epoxide-terminated prepolymers. The term "monoepoxide compound" is meant to refer to an epoxide compound having one epoxy group. The term "polyepoxide compound" is meant to refer to an epoxide compound having at least two epoxy groups. The term "diepoxide compound" is meant to refer to an epoxide compound having two epoxy groups.

[0027] The epoxides may be unsubstituted or inertly substituted. Examples of inert substituents include chlorine, bromine, fluorine and phenyl.

[0028] The epoxy-functional silicone-based resin a) and the optionally elastomer-modified epoxy resin b) are different substances and, if both are present, one resin cannot act as both a) and b).

[0029] As used herein, "C1-C n An "alkyl" group refers to a monovalent group containing 1 to n carbon atoms, is an alkane radical, and includes straight-chain and branched-chain organic groups. Thus, "C1-C 30An "alkyl" group refers to a monovalent group containing 1 to 30 carbon atoms, is an alkane radical, and includes straight-chain and branched-chain organic groups. Examples of alkyl groups include, but are not limited to, methyl; ethyl; propyl; isopropyl; n-butyl; isobutyl; sec-butyl; tert-butyl; n-pentyl; n-hexyl; n-heptyl, and 2-ethylhexyl. In the present invention, such alkyl groups may be unsubstituted or substituted with one or more substituents, such as halo, nitro, cyano, amido, amino, sulfonyl, sulfinyl, sulfanyl, sulfoxy, urea, thiourea, sulfamoyl, sulfamido, and hydroxy. Halogenated derivatives of the above-listed hydrocarbon groups may be specifically cited as examples of suitable substituted alkyl groups. In general, however, unsubstituted alkyl groups containing 1 to 18 carbon atoms (C 1- C 18 alkyl), for example, unsubstituted alkyl groups containing 1 to 12 carbon atoms (C 1- C 12 alkyl) or unsubstituted alkyl groups containing 1 to 6 carbon atoms (C 1- It should be noted that C6 alkyl) is preferred.

[0030] The term “C 3- C 30 "Cycloalkyl" is understood to mean a saturated monocyclic, bicyclic or tricyclic hydrocarbon group having 3 to 30 carbon atoms. Generally, cycloalkyl groups (C 3- C 18 It should be noted that cycloalkyl groups are preferred. Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, adamantane, and norbornane.

[0031] As used herein, "C 6- C 18"Aryl" groups, used alone or as part of a larger moiety (as in "aralkyl groups"), refer to optionally substituted monocyclic, bicyclic and tricyclic ring systems, where the monocyclic ring system is aromatic or ring system, or where at least one ring in the bicyclic or tricyclic ring system is aromatic. Bicyclic and tricyclic ring systems include benzo-fused 2-3 membered carbocyclic rings. Examples of aryl groups include: phenyl; indenyl; naphthalenyl, tetrahydronaphthyl, tetrahydroindenyl; tetrahydroanthracenyl; and anthracenyl. It should also be noted that the phenyl group may be preferred in some cases.

[0032] As used herein, "C2-C 20 An "alkenyl" group refers to a hydrocarbyl group having from 2 to 20 carbon atoms and at least one unit of ethylenic unsaturation. The alkenyl group may be straight, branched, or cyclic, and may be optionally substituted. The term "alkenyl" also encompasses groups having "cis" and "trans" configurations, or alternatively, "E" and "Z" configurations, as will be appreciated by those skilled in the art. Generally, however, groups having from 2 to 10 (C 2-10 ) or 2 to 8 (C 2-8 It should be noted that unsubstituted alkenyl groups containing carbon atoms of 2-12Examples of alkenyl groups include, but are not limited to, -CH=CH2; -CH=CHCH3; -CH2CH=CH2; -C(=CH2)(CH3); -CH=CHCH2CH3; -CH2CH=CHCH3; -CH2CH2CH=CH2; -CH=C(CH3)2; -CH2C(=CH2)(CH3); -C(=CH2)CH2CH3; -C(CH3)=CHCH3; -C(CH3)CH=CH2; -CH=CHCH2CH2CH3; -CH2CH=CHCH 2CH3;-CH2CH2CH=CHCH3;-CH2CH2CH2CH=CH2;-C(=CH2)CH2CH2CH3;-C(CH3)=CHCH2CH3;-CH(CH3)CH=CHCH;-CH(CH3)CH2CH=CHCH;-CH(CH3)CH2CH=CH2;-CH2CH=C(CH3)2;1-cyclopent-1-enyl;1-cyclopent-2-enyl;1-cyclopent-3-enyl;1-cyclohex-1-enyl;1-cyclohex-2-enyl; and, 1-cyclohexyl-3-enyl.

[0033] As used herein, "alkylaryl" refers to an alkyl substituted aryl group and "substituted alkylaryl" refers to an alkylaryl group further bearing one or more substituents as set forth above.

[0034] The term "hetero" as used herein refers to groups or moieties that contain one or more heteroatoms, such as N, O, Si, and S. Thus, for example, "heterocyclic" refers to cyclic groups having, for example, N, O, Si, or S as part of the ring structure. "Heteroalkyl" and "heterocycloalkyl" moieties are alkyl and cycloalkyl groups, as defined above, that contain N, O, Si, or S as part of their structure, respectively.

[0035] As used herein, unless otherwise specified, the term "catalytic amount" means a substoichiometric amount of catalyst relative to a reactant.

[0036] As used herein, a "primary amino group" refers to an NH group attached to an organic group, and a "secondary amino group" refers to an NH group attached to two organic groups, which together may be part of a ring. As used, the term "amine hydrogen" refers to the hydrogen atoms of primary and secondary amino groups.

[0037] · When "amine value" is mentioned herein, this can be determined by titration of the amine acetate ion with a dilute, usually 1N HCl solution. In case of pure substances, the amine value can be calculated using the molecular weight of the pure compound and KOH (56.1 g / mol). Useful guidance can be found for illustration at https: / / dowac.custhelp.com / app / answers / detail / a_id / 12987. In the context of the present invention, a "two-component (2K) composition" is understood to be a composition in which the binder component (A) and the hardener component (B) must be stored in separate containers due to their (high) reactivity. The two components are mixed only immediately before application and then react to form bonds, usually without additional activation, thereby forming a polymer network. Here, a higher temperature is applied to promote the crosslinking reaction.

[0038] The viscosity of the coating compositions described herein is measured at standard conditions of 20°C and 50% relative humidity (RH) using a Brookfield Viscometer, Model RVT, unless otherwise specified. The viscometer is calibrated using silicone oils of known viscosity varying from 5,000 cps to 50,000 cps. A set of RV spindles attached to the viscometer are used for the calibration. Measurements of the coating compositions are taken at a speed of 20 revolutions per minute using a No. 6 spindle for 1 minute until the viscometer is equilibrated. The viscosity corresponding to the equilibrated reading is then calculated using the calibration.

[0039] As used herein, the term "polyol" includes diols and higher functionality hydroxyl compounds.

[0040] Hydroxyl (OH) numbers given herein are measured according to Japanese Industrial Standards (JIS) K-1557, 6.4. Isocyanate content values ​​given herein are measured according to EN ISO 1 1909.

[0041] Molecular weights referred to herein can be determined by gel permeation chromatography (GPC), as performed in accordance with ASTM 3536, using polystyrene calibration standards.

[0042] As used herein, "anhydrous" means that the relevant composition contains less than 0.25% water by weight. For example, the composition may contain less than 0.1% water by weight or may be completely free of water. The term "essentially free of solvent" should be similarly understood to mean that the relevant composition contains less than 0.25% solvent by weight.

[0043] Detailed Description of the Invention a) Silicone-based resin containing epoxy functional groups The two (2K) component composition of the present invention typically comprises a) a silicone-based resin containing epoxy functional groups in an amount of 10-60% by weight, preferably 10-40% by weight, based on the weight of the first component thereof. In another expression of a preferred configuration of the present composition, which is not intended to be mutually exclusive with the above description, the composition may contain 5-40% by weight of the silicone-based resin containing epoxy functional groups a) based on the weight of the composition. For example, the composition of the present invention may contain 5-30% by weight, for example 5-20% by weight, of said silicone-based resin containing epoxy functional groups a) based on the weight of the total composition.

[0044] Silicone resins containing epoxy functional groups exhibit the properties of silicone resins, but also contain epoxy moieties that can be crosslinked by epoxy curing agents as described herein. In particular, silicone resins containing epoxy functional groups preferably contain alkoxy silicone moieties. Typically, silicone resins containing epoxy functional groups are silicone-epoxy elastomers. Such silicone resins containing epoxy functional groups can be obtained from at least one epoxy resin and at least one alkoxy-silicone resin. Typically, they are obtained by reacting at least one epoxy resin with at least one alkoxy silicone resin, preferably with at least one hydroxyl functional compound, and they can be obtained by reacting at least one epoxy resin with at least one alkoxy silicone resin, preferably with at least one hydroxyl functional compound. Aliphatic epoxy resins are particularly preferred. Preferably, the silicone resins containing epoxy functional groups are liquid at ambient temperature and pressure. In this regard, it is preferred that the silicone-based resin containing epoxy functionality has a viscosity in the range of 500 to 2500 mPa s, preferably in the range of 800 to 2200 mPa s, more preferably in the range of 1000 to 2000 mPa s, and even more preferably in the range of 1200 to 1800 mPa s, according to ASTM D445 at 25° C. Higher or lower viscosities have been found to be impractical within the scope of the present disclosure.

[0045] The silicone resin containing epoxy functional groups generally contains an epoxy moiety that provides crosslinking power to the curing agent as described herein. With respect to the epoxy moiety present in the silicone resin containing epoxy functional groups, the silicone resin containing epoxy functional groups preferably has an epoxy equivalent weight according to ASTM D1652 in the range of 100 to 1500 g / eq, preferably in the range of 200 to 1000 g / eq, more preferably in the range of 300 to 700 g / eq. An example of a silicone resin containing epoxy functional groups that can be advantageously used within the scope of the present disclosure is Silikopon® EF (Evonik Industries).

[0046] b) Elastomer-modified epoxy resin The two-component (2K) composition of the present invention necessarily comprises an elastomer-modified epoxy resin, which should desirably have an epoxide equivalent weight of 200 to 2500 g / eq., for example 200 to 500 g / eq.

[0047] Without intending to limit the invention, it is preferred that the elastomer-modified epoxy resin b) constitutes 1 to 40 weight percent, preferably 5 to 30 weight percent, of the first component of the composition. In another expression of a desirable configuration of the present composition, which is not intended to be mutually exclusive with the above, the composition contains 1 to 20 weight percent, preferably 1 to 15 weight percent, of the elastomer-modified epoxy resin b), based on the weight of the total composition.

[0048] The elastomer modification of the epoxy resin (hereinafter referred to as E1) may be carried out by any suitable method known to those skilled in the art, but should generally be carried out by a catalytic addition reaction between the functional group of the modifier (hereinafter referred to as M1) and the oxirane group of the epoxy resin (E1). Such an addition reaction may be carried out in a suitable solvent under at least one of the following conditions: i) temperature 40°C to 200°C; ii) reaction time 0.5 to 5 hours; iii) catalysis. Examples of catalysts include: tertiary amine catalysts such as tributylamine; quaternary ammonium salts, such as tetrabutylammonium chloride; tertiary phosphates, such as triphenyl phosphate; quaternary phosphonium salts, such as ethyltriphenylphosphonium iodide (ETPPI); metal salts, such as AMC-2 (chromium salt of octanoic acid); and combinations thereof, where a stepwise addition reaction is carried out.

[0049] The epoxy resin (E1) to be modified has a 1,2-epoxy equivalent greater than 1, preferably at least 2. The epoxy resin (E1) may be linear or branched, saturated or unsaturated, aliphatic, cycloaliphatic, aromatic or heterocyclic. Examples of epoxy resins (E1) include: polyglycidyl ethers of polyhydric compounds; brominated epoxies; epoxy novolacs or similar polyhydroxyphenolic resins; polyglycidyl ethers of glycols or polyglycols; and polyglycidyl esters of polycarboxylic acids. It is noted that it is preferable to use polyglycidyl ethers of polyhydric phenols as the epoxy resin (E1).

[0050] The functionalized modifier (M1) is functionalized, either terminally or non-terminally, with a group reactive to the oxirane group of the epoxy resin (E1). Suitable functional groups include, but are not limited to, carboxyl; amino; hydroxyl; epoxy; mercaptan; anhydride; and isocyanate. Furthermore, the modifier (M1) may be a functionalized homopolymer or a functionalized random, block, or star copolymer.

[0051] In an important embodiment, the functional modifier (M1) used to modify the epoxy resin (E1) has the general formula: XBX is a functional group-terminated diene-containing polymer having the formula Where: B is a polymer backbone polymerized from monomers selected from: 4- C 10 Diene;C 4- C 10 A diene and at least one vinyl aromatic monomer, such as styrene, C 1- C6 alkyl-substituted styrene or halogen-substituted styrene; C 4- C 10 A diene and at least one vinyl nitrile monomer, such as acrylonitrile or methacrylonitrile;4- C 10 a diene, at least one vinyl nitrile monomer and at least one vinyl aromatic monomer; or C 4- C 10 a diene, at least one vinyl nitrile monomer and a compound of the formula CH2=CR-COOR 1 where R and R 1 are each independently hydrogen or C 1- C 10 alkyl groups); and X may be any functional group capable of reacting with an oxirane group, suitable examples of which include carboxy, amino, hydroxyl, epoxy, mercaptan, anhydride and isocyanate groups.

[0052] As reactant modifier (M1), the functional group-terminated diene-containing polymer should typically be characterized by a functionality of 1.1 to 2.5, for example 1.5 to 2.5, or 1.6 to 2.4, although this does not exclude that the polymer backbone (X) is partially hydrogenated.

[0053] As non-limiting examples, the functionally terminated diene-containing polymer (M1) may be selected from: carboxyl-terminated polybutadiene; carboxyl-terminated poly(butadiene-acrylonitrile); and carboxyl-terminated poly(butadiene-acrylonitrile-acrylic acid).

[0054] Modifiers (M1) for carboxyl-terminated poly(butadiene-acrylonitrile) (CTBN) may be noted as being preferred, in particular carboxyl-terminated poly(butadiene-acrylonitrile) (CTBN) composed of: 5-30% by weight of acrylonitrile; and 70-95% by weight of butadiene. Independently of or in addition to this composition, the carboxyl-terminated poly(butadiene-acrylonitrile) (CTBN) should have a number average molecular weight (Mn) of 1000-50000 g / mol, for example 2000-10000 g / mol. Furthermore, the carboxyl-terminated poly(butadiene-acrylonitrile) is not excluded from containing, in addition to the terminal carboxyl groups, other functional groups pendant on the chain (for example, amino groups, phenolic groups, hydroxyl groups, epoxy groups, mercaptan groups or anhydride groups).

[0055] Apart from the functional group-terminated diene-containing polymers, the use of diene-containing polymers that are non-terminally functionalized along the chain backbone may be useful in some embodiments. Such functionalized polymers (M1) include, for example, carboxylated polybutadiene; carboxylated poly(butadiene-styrene); midblock carboxylated poly(styrene-ethylene / butadiene-styrene); amidated poly(butadiene-styrene); mercaptopolybutadiene; epoxidized polybutadiene; and epoxidized poly(butadiene-styrene).

[0056] In a further embodiment of the present invention, the two-component (2K) composition is characterized in that said at least one elastomer-functionalized epoxy resin comprises or consists of at least one urethane-modified epoxy resin. In this embodiment, the functionalized modifier (M1) modifying the epoxy resin (E1) is an isocyanate-terminated urethane prepolymer obtained by reacting a polyisocyanate compound (I) with a polyhydroxyl (P) compound. Without intending to limit this embodiment, the urethane prepolymer (M1) should be characterized by: i) an NCO content of 5 to 30% by weight, preferably 10 to 25% by weight, based on the prepolymer; ii) a functionality of 1.1 to 2.5. These characteristic properties can be found in known commercially available prepolymers. Alternatively, components (I) and (P) may be reacted in a ratio and under conditions such that these properties of the resulting prepolymer are achieved.

[0057] The polyisocyanate (I) used to prepare the prepolymer (M1) includes any aliphatic, cycloaliphatic, arylaliphatic, heterocyclic or aromatic polyisocyanate, or mixtures thereof, having an average isocyanate functionality of at least 2.0 and an equivalent weight of at least 80. The isocyanate functionality of the polyisocyanate (I) is more typically 2.2 to 4.0, for example 2.3 to 3.5. Functionalities greater than 4.0 may be used, but their use may result in excessive crosslinking. The equivalent weight of the polyisocyanate is typically 100 to 300, preferably 110 to 250, more preferably 120 to 200.

[0058] The polyisocyanates may, if desired, be biuretized and / or isocyanurated by commonly known methods such as those described in GB Patent No. 889,050.

[0059] Examples of suitable polyisocyanates (I) include, but are not limited to, ethylene diisocyanate; 1,4-tetramethylene diisocyanate; hexamethylene diisocyanate (HDI); biuret or trimer of HDI; 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3- and 1,4-diisocyanate, and mixtures of these isomers; 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane; 2,4- and 2,6-hexahydrotolylene diisocyanate, and mixtures of these isomers; hexahydrol, 3- and / or 1,4-phenylene diisocyanate; perhydro-2,5'- and / or 4,4'-diphenylmethane diisocyanate; 1,3- and 1,4-phenylene diisocyanate; 2,4- and 2,6-tolylene diisocyanate and mixtures of these isomers; diphenylmethane-2,4'- and / or 4,4'-diisocyanate (MDI); naphthylene-1,5-diisocyanate; triphenylmethane-4,4',4'-triisocyanate; and polyphenylpolymethylene polyisocyanates of the type obtained by condensation of aniline with formaldehyde followed by phosgenation, as described in British Patents Nos. 874,430 and 848,671. It should be noted that diisocyanates and / or polyisocyanates containing ester, urea, allophanate, carbodiimide, uretdione and / or urethane groups may also be used in the process according to the invention.

[0060] The polyhydroxyl compound (P) used to derive the urethane prepolymer (M1) should usually have a number average molecular weight (Mn) of 400 to 10,000 g / mol. The hydroxyl value of the polyhydroxyl compound (P) is usually 20 to 850 mgKOH / g, preferably 25 to 500 mgKOH / g. Furthermore, the polyhydroxyl compound (P) is desirably selected from divalent or higher polyvalent polyether polyols, polyester polyols, poly(ether ester) polyols, poly(alkylene carbonate) polyols, hydroxyl-containing polythioethers, polymer polyols, and mixtures thereof.

[0061] Low molecular weight diols and triols, for example 60 to 400 or 300 g / mol, may be reactive towards isocyanates (I), these polyols are usually used only as starter molecules, chain extenders and / or crosslinkers in reaction mixtures containing one or more active hydrogen compounds (P). In this regard, mention may be made of aliphatic, cycloaliphatic and / or araliphatic diols having 2 to 14, preferably 4 to 10, carbon atoms, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, o-, m-, p-dihydroxycyclohexane; diethylene glycol; dipropylene glycol; bis(2-hydroxyethyl)hydroquinone; and triols such as 1,2,4- and 1,3,5-trihydroxycyclohexane, glycerol, trimethylolpropane.

[0062] Polyether polyols are well known in the art and include polyoxyethylene, polyoxypropylene, polyoxybutylene, and polytetramethylene ether diols and triols. Polyether polyols can generally have a weight average molecular weight (Mw) of 400 to 10,000 g / mol, e.g., 1,000 to 7,000 g / mol, and are prepared by polymerizing alkylene oxides in the presence of active hydrogen-containing initiator compounds, e.g., as described in U.S. Pat. Nos. 4,269,9945, 4,218,543, and 4,374,210. The alkylene oxide monomers are typically selected from the group consisting of: ethylene oxide, propylene oxide; butylene oxide; styrene oxide; epichlorohydrin; epibromohydrin; and mixtures thereof. The active hydrogen initiator is typically selected from the group consisting of: water; ethylene glycol; propylene glycol; butanediol; hexanediol; glycerin; trimethylolpropane; pentaerythritol; hexanetriol; sorbitol; sucrose; hydroquinone; resorcinol; catechol; bisphenol; novolac resins; phosphoric acid; amines; and mixtures thereof.

[0063] As known in the art, polyester polyols can be prepared by reacting a polycarboxylic acid or anhydride with a polyhydric alcohol. Examples of suitable polycarboxylic acids include succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, maleic acid, trimellitic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, endomethylene tetrahydrophthalic anhydride, maleic anhydride, glutaric anhydride, fumaric acid, and mixtures thereof. Examples of polyhydric alcohols useful in preparing polyester polyols include ethylene glycol, propanediol, butanediol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, glycerol, trimethylolpropane, pentaerythritol, quinitol, mannitol, sorbitol, methylglycoside, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, polypropylene glycol, and mixtures thereof. For the present invention, useful polyester polyols typically have a weight average molecular weight (Mw) of 1000 to 10000 g / mol.

[0064] In one embodiment of the invention, the reactant polyhydroxyl compound (P) has an average functionality of at least 1.5, preferably at least 1.8, more preferably at least 2.0, but not greater than 4.0, preferably not greater than about 3.5, more preferably not greater than 3.0. Independently or additionally, the equivalent weight of the reactant polyhydroxyl compound (P) is at least 200 g / eq., preferably at least 500 g / eq., more preferably at least 1,000 g / eq., but not greater than 3500 g / eq., preferably not greater than 3000 g / eq., more preferably not greater than 2500 g / eq.

[0065] Starting from the components (P) and (I) defined above, the polyurethane prepolymer (M1) can be prepared under anhydrous conditions by any suitable method, such as bulk polymerization and solution polymerization. The polyhydroxyl compound (P) is present in an amount sufficient to react with most of the isocyanate groups, but leaves enough isocyanate groups to correspond to the desired free isocyanate content of the urethane prepolymer (M1). And in the embodiment in which the polyhydroxyl compound (P) comprises a mixture of diols and triols, the ratio of diols and triols must be selected to achieve the desired isocyanate functionality of the urethane prepolymer (M1).

[0066] In a further preferred embodiment of the present invention, the two-component (2K) composition is characterized in that said at least one elastomer-functionalized epoxy resin b) comprises or consists of at least one dimer acid modified epoxy resin. The dimer acid modifier (M1) may be cyclic or acyclic, but is usually a C36-C44 aliphatic diacid that can be prepared by oxidative coupling of C18-C22 unsaturated monoacids. Dimer acids obtained by oxidative coupling of oleic acid, linoleic acid or tall fatty acids can be mentioned as examples of dimer acid modifier (M1).

[0067] In view of the preferred embodiments discussed hereinabove, commercially available examples of suitable elastomer-modified epoxy resins include: Hypox® resins, including Hypox DA 323, available from CVC Thermosets; EPON 58005 and EPON 58034, available from Miller-Stephenson; JER871 and JER872, available from Mitsubishi Chemical Corporation; B-Tough A1, A2, and A3, available from Croda Coatings and Polymers; YD-171 and YD-172, available from Nippon Steel Chemical Co., Ltd.; and EPU-6, EPU-7N, EPU-11F, EPU-15F, EPU-1395, EPU-738, EPU-17, EPU-17T-6, and EPU-80, available from ADEKA Corporation.

[0068] c) Hardener The curing agent c) must consist of at least one compound having at least two epoxide-reactive groups per molecule, and is characterized in that the curing agent contains at least one alkoxy-containing amino-functional silicone resin. The epoxide-reactive group is a group capable of reacting with an epoxy group. The alkoxy-containing amino-functional silicone resin should be characterized in that it has at least one of the following: i) an amine hydrogen equivalent of 80 or 100 to 1500 g / eq., preferably 150 to 700 g / eq., for example 200 to 500 g / eq.; and ii) a weight average molecular weight (Mw) measured by gel permeation chromatography of 150 to 10000 g / mol, preferably 150 to 8,000 g / mol, for example 150 to 5,000 g / mol.

[0069] In an important embodiment of the present invention, the curing agent c) is at least one alkoxy-containing amino-functional silicone resin (C) having at least two amine hydrogen atoms per molecule, an amine hydrogen equivalent weight of 100 to 1500 g / eq., and a total alkoxy content (AC) of 10 to 40 mole % based on the number of moles of silicon. 1 ) or consisting of the resin (C 1 ) includes the following units: [ka] Where: Each R is independently 1- C 18 Alkyl group, C 6- C 18 An aryl group, or a group of the formula -R 2 NHR 3 or -R 2 NHR 2 NHR 3 and each R is selected from an amino-functional hydrocarbon group having the formula: 2 is independently C 2- C 20 is an alkylene group, R 3 is C 1- is a C6 alkyl group; a, b, c, and d respectively define the mole fractions of each of the units (i) to (iv) such that a+b+c+d=1; and w, x, y, and z define the mole fraction of alkoxy groups such that 0≦w<1, 0≦x<2, 0≦y<3, and 0≦z<4, and are selected to satisfy the Total Alkoxy Content (AC) defined above.

[0070] In a preferred embodiment, C 1 Each R in 1- C 12 Alkyl group, C 6- C 18 An aryl group, or a group of the formula -R 2 NHR 3 or -R 2 NHR 2 NHR 3 wherein each R 2 is independently C 2- C 12 is an alkylene group, R 3 is C 1- It is a C4 alkyl group.

[0071] In a particularly preferred embodiment, C 1 Each R in 1- C6 alkyl group, C 6- C 18 An aryl group, or a group of the formula -R 1 NHR 2 or -R 1 NHR 1 NHR 2 wherein each R 1 is independently C 2- C8 alkylene group, R 2 is C 1- C2 alkyl group. Definitely preferred are amino-functional silicone resins (C 1 ).

[0072] As mentioned above, the amino-functional silicone resin (C 1) The subscripts a, b, c, and d represent the molar fractions of each unit such that a + b + c + d = 1. These molar fractions should satisfy the following conditions: i) a has a value of 0 to 0.40, preferably 0 to 0.20, for example 0 to 0.10; ii) b has a value of 0.15 or more, preferably 0.15 to 0.8, for example 0.15 to 0.6; iii) c satisfies the condition 0 < c < 0.85, preferably 0 < c < 0.80; iv) d has a value of 0 to 0.20, preferably 0 to 0.10, for example 0 to 0.05.

[0073] One skilled in the art will recognize that the total alkoxy content (AC) of the alkoxy-containing amino-functional silicone resin (C 1 ) is represented by the sum of (wa) + (xb) + (yc) + (zd). Desirably, the total alkoxy content should be in the range of 10 to 30 mole percent, preferably in the range of 10 to 25 mole percent, or in the range of 10 to 20 mole percent, based on the number of moles of silicon in the resin.

[0074] Although there is no intention to limit the method for preparing the alkoxy-containing amino-functional silicone resin (C1) described herein, the disclosure of US2012 / 0251729 (Horstman et al.) is useful regarding an exemplary synthesis process.

[0075] Although there is no intention to limit the present invention, examples of alkoxy-containing amino-functional silicone resins that are useful as curing agent c) or in curing agent c) may include: γ-aminopropyltriethoxysilane; γ-aminopropyltriethoxysilane; γ-aminopropyltrimethoxysilane; γ-aminopropylsilsesquioxane; -aminopropyltrimethoxysilane; N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane; benzylamino-silane; bis-(γ-triethoxysilylpropyl)amine; bis-(γ-trimethoxysilylpropyl)amine; N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane; and N-ethyl-3-trimethoxysilyl-methylpropamine.

[0076] The following commercially available alkoxy-containing amino-functional silicone resins may also be useful: Silquest A-1130, Silquest A-1387, Silquest Y-19139, Silquest VX 225, and Silquest Y-15744, available from Momentive Performance Materials Inc; and HP2000, available from Wacker Chemie.

[0077] It is preferred that the curing agent c) consists or consists essentially of said alkoxy-containing amino-functional silicone, although the presence of other curing agents in an amount of up to 10 mol %, based on the total moles of said alkoxy-containing amino-functional silicone, is not excluded by the present invention. Co-curing agents include in particular mercapto compounds having at least two mercapto groups reactive towards epoxide groups, or at least one polyamine compound without alkoxy functionality.

[0078] When formulating a curable composition, it is preferred that the composition is characterized by a molar ratio of epoxide-reactive groups:epoxide groups of from 1.5:1 to 1:1.5, such as from 1.1:1 to 1:1.1. In particular, a molar ratio of epoxide-reactive groups:epoxide groups of 1:1 is included within these recited ranges and as such represents a highly preferred molar ratio.

[0079] Additives and auxiliary ingredients The compositions obtained in the present invention typically further comprise auxiliary agents and additives that can give these compositions improved properties. For example, auxiliary agents and additives can give one or more of the following: improved elastic properties; improved elastic recovery; longer effective processing time; faster curing time; and lower residual tack. Such auxiliary agents and additives include plasticizers, stabilizers including UV stabilizers, antioxidants, reinforcing agents, fillers, reactive diluents, drying agents, adhesion promoters, bactericides, flame retardants, rheological auxiliary agents, color pigments or color pastes, and / or optionally small amounts of non-reactive diluents (which can be included in one or both components of two-component (2K) compositions independently of each other).

[0080] For the sake of completeness, it is noted that auxiliary materials and additives that contain epoxide-reactive groups are generally blended into the hardener component of a two (2K) component composition. Materials that contain epoxide groups or that react with the hardener are generally blended into the epoxide-containing component of a two (2K) component composition. Non-reactive materials may be blended into either or both of the A and B components.

[0081] "Plasticizer" for the purposes of the present invention is a substance that reduces the viscosity of the composition and thus promotes its processability.Here, the plasticizer can constitute up to 10% by weight, or up to 5% by weight, based on the total weight of the composition, and is preferably selected from the group consisting of: polydimethylsiloxane (PDMS); diurethane; ethers of monofunctional linear or branched C4-C16 alcohols, such as Cetiol OE (available from Cognis Deutschland GmbH, Dusseldorf); esters of abietic acid, butyric acid, thiobutyric acid, acetic acid, propionic acid and citric acid; esters based on nitrocellulose and polyvinyl acetate; fatty acid esters; dicarboxylic acid esters; esters of fatty acids or epoxidized fatty acids with OH groups; glycolic acid esters; benzoic acid esters; phosphoric acid esters; sulfonic acid esters; trimellitic acid esters; epoxidized plasticizers; polyether plasticizers such as end-capped polyethylene or polypropylene glycol; polystyrene; hydrocarbon-based plasticizers; chlorinated paraffins; and mixtures thereof. It should be noted that in principle phthalates could be used as plasticizers, but these are not preferred due to their potential toxicity.Preferably, the plasticizer comprises or consists of one or more polydimethylsiloxanes (PDMS).

[0082] "Stabilizer" for the purposes of the present invention should be understood as antioxidant, UV stabilizer or hydrolysis stabilizer. Herein, the stabilizer can constitute up to 10% by weight, or up to 5% by weight, in total, based on the total weight of the composition. Standard commercial examples of stabilizers suitable for use herein include: sterically hindered phenols; thioethers; benzotriazoles; benzophenones; benzoates; cyanoacrylates; acrylates; amines of the hindered amine light stabilizer (HALS) type; phosphorus; sulfur; and mixtures thereof.

[0083] These compositions of the present invention may optionally contain reinforced rubber in the form of core-shell particles dispersed in an epoxy resin matrix. The term "core-shell rubber" or CSR is used according to its standard meaning in the art to refer to a rubber particle core formed by a polymer containing an elastomeric or rubbery polymer as a major component, and a shell layer formed by a polymer grafted onto the core. The shell layer partially or entirely covers the surface of the rubber particle core in the graft polymerization process. By weight, the core should constitute at least 50% by weight of the core-shell rubber particle.

[0084] The core polymer material has a glass transition temperature (T g ), preferably −20° C. or less, more preferably −40° C. or less, and even more preferably −60° C. or less. g The shell polymer should have a glass transition temperature (T) above room temperature, preferably above 30° C., and more preferably above 50° C. g ) is a non-elastomeric, thermoplastic or thermosetting polymer having a

[0085] Without intending to limit the invention, the core may be composed of diene homopolymers, such as homopolymers of butadiene or isoprene; diene copolymers, such as copolymers of butadiene or isoprene with one or more ethylenically unsaturated monomers, such as the vinyl aromatic monomers (meth)acrylonitrile or (meth)acrylate; polymers based on (meth)acrylic acid ester monomers, such as polybutyl acrylate; and polysiloxane elastomers, such as polydimethylsiloxane and crosslinked polydimethylsiloxane.

[0086] Similarly, without intending to limit the invention, the shell may comprise a polymer or copolymer of one or more monomers selected from the following: (meth)acrylates such as methyl methacrylate; vinyl aromatic monomers such as styrene; vinyl cyanides such as acrylonitrile; unsaturated acids and anhydrides such as acrylic acid; and (meth)acrylamides. The polymers or copolymers used in the shell may have acid groups that are ionically crosslinked through the formation of metal carboxylates, particularly through the formation of salts of divalent metal cations. The shell polymer or copolymer may be covalently crosslinked by monomers having two or more double bonds per molecule.

[0087] Any core-shell rubber particles present preferably have an average particle size (d50) between 10 nm and 300 nm, for example between 50 nm and 200 nm, said particle size referring to the diameter or maximum dimension of a particle in a distribution of particles, as measured by dynamic light scattering.

[0088] This application does not preclude the presence of two types of core-shell rubber (CSR) particles having different particle sizes in the composition to provide a balance of important properties of the resulting cured product, including shear strength, peel strength and resin fracture toughness. In this embodiment, the smaller particles (1 st CSR type) may have an average particle size of 10 to 100 nm and may contain larger particles (2 nd The smaller core-shell rubber particles should typically be used in excess of the larger particles on a weight basis: for example, a weight ratio of smaller CSR particles to larger CSR particles of 3:1 to 5:1 may be used.

[0089] The core-shell rubber may be selected from commercial sources, such as Paraloid EXL 2650A, EXL 2655 and EXL2691 A available from The Dow Chemical Company; the Kane Ace® MX series available from Kaneka Corporation, in particular MX 120, MX 125, MX 130, MX 136, MX 551, MX 553; and METABLEN SX-006 available from Mitsubishi Rayon.

[0090] The core-shell rubber particles should be present in the composition in an amount of 0-10% by weight, such as 0-5% by weight, based on the total weight of the composition.

[0091] As mentioned above, the compositions of the invention can further contain fillers. Suitable here are, for example, chalk, lime powder, precipitated and / or pyrogenic silicic acid, zeolites, bentonite, magnesium carbonate, diatomaceous earth, alumina, clay, talc, titanium oxide, iron oxide, zinc oxide, sand, quartz, flint, mica, glass powder and other mineral grounds. Organic fillers can also be used, in particular carbon black, graphite, wood fibers, wood flour, sawdust, cellulose, cotton, pulp, cotton, wood chips, chopped straw, rice husk, crushed walnut shells and other chopped fibers. Short fibers such as glass fibers, glass filaments, polyacrylonitrile, carbon fibers, Kevlar® fibers or polyethylene fibers can also be added. Aluminum powder is also suitable as a filler.

[0092] Pyrolytic and / or precipitated silicic acid is 10-90m 2 / g. When used, they do not further increase the viscosity of the compositions of the invention, but contribute to the toughening of the cured composition.

[0093] Higher BET surface area, advantageously 100-250 m 2 / g, especially 110-170m 2It is also conceivable to use pyrogenic and / or precipitated silicic acids as fillers, which have a BET surface area of ​​0.1 g / g. Due to the higher BET surface area, the reinforcing effect of the set composition is achieved with a smaller proportion by weight of silicic acid.

[0094] Hollow spheres with a mineral or plastic shell are also suitable as fillers. These can be, for example, hollow glass spheres, which are commercially available under the trade name Glass Bubbles®. Plastic-based hollow spheres, such as Expancel® or Dualite®, can also be used, which are described in EP 0 520 426 B1: they are composed of inorganic or organic materials and have a diameter of less than or equal to 1 mm, preferably less than or equal to 500 μm, respectively.

[0095] Fillers that impart thixotropic properties to the composition may be preferred for many applications: such fillers are also described as rheological aids, for example hydrogenated castor oil, fatty acid amides, or swellable plastics such as PVC.

[0096] The total amount of filler present in the composition of the present invention will preferably be 0-30% by weight, more preferably 0-20% by weight, based on the total weight of the composition. The desired viscosity of the curable composition is usually determined by the total amount of filler added, and in order to be easily extruded from a suitable dispensing device such as a tube, the curable composition should have a viscosity of 3000-150,000, preferably 40,000-80,000 mPas, or even 50,000-60,000 mPas.

[0097] It should be noted that compounds having metal chelating properties may be used in the compositions of the present invention to help improve adhesion of the cured adhesive to the substrate surface. Additionally, an acetoacetate-functionalized modified resin sold by King Industries under the trade name K-FLEX XM-B301 is also suitable for use as an adhesion promoter.

[0098] Examples of suitable ingredients are titanium dioxide, iron oxide, or carbon black.

[0099] To further extend the shelf life, it is often advisable to further stabilize the composition of the invention with respect to the penetration of moisture using a desiccant. There is also sometimes a need to reduce the viscosity of the adhesive or sealant composition according to the invention for a particular application by using a reactive diluent. The total amount of reactive diluent present is typically up to 15% by weight, preferably 0.5 to 5% by weight, based on the total weight of the composition. Preferably, a silanol is present as the diluent.

[0100] The presence of solvents and non-reactive diluents in the composition of the invention is also not excluded, which can effectively reduce its viscosity. For example, and by way of example only, the compositions of the present invention may contain one or more of the following: xylene; 2-methoxyethanol; dimethoxyethanol; 2-ethoxyethanol; 2-propoxyethanol; 2-isopropoxyethanol; 2-butoxyethanol; 2-phenoxyethanol; 2-benzyloxyethanol; benzyl alcohol; ethylene glycol; ethylene glycol dimethyl ether; ethylene glycol diethyl ether; ethylene glycol dibutyl ether; ethylene glycol diphenyl ether; diethylene glycol; diethylene glycol monomethyl ether; diethylene glycol monoethyl ether; diethylene glycol-mono-n-butyl ether; diethylene glycol dimethyl ether; diethylene glycol diethyl ether; diethylene glycol di-n-butyryl ether; propylene glycol butyl ether; propylene glycol phenyl ether; dipropylene glycol; dipropylene glycol monomethyl ether; dipropylene glycol dimethyl ether; dipropylene glycol di-n-butyl ether; N-methylpyrrolidone; diphenylmethane; diisopropyl naphthalene; Solvesso® products (Exxon petroleum distillates, such as those available from Polypropylene Inc.; alkylphenols, such as tert-butylphenol, nonylphenol, dodecylphenol, and 8,11,14-pentadecatrienylphenol; styrenated phenols; bisphenols; aromatic hydrocarbon resins, especially those containing phenolic groups such as ethoxylated or propoxylated phenols; adipates; sebacates; phthalates; benzoates; organic phosphates or sulfonates; and sulfonamides.

[0101] Apart from the above, it is preferred that the solvents and non-reactive diluents together constitute less than 10% by weight, especially less than 5% by weight, or even less than 2% by weight, based on the total weight of the composition.

[0102] For completeness, the compositions of the invention may also include one or more monoamines, such as hexylamine and benzylamine.

[0103] To enhance physical properties, the two-component (2K) composition preferably further comprises a trialkoxy-functional silicone prepolymer different from resin a). This prepolymer is condensation curable and can aid in crosslinking. Preferably, the two-component (2K) composition further comprises a trimethoxysilicone prepolymer. Examples are commercially available under the trade name Silmer TMS, such as Silmer TMS Di-400. In a preferred embodiment, the trialkoxy-functional silicone prepolymer is present in an amount of 0.1 to 5 wt. %, more preferably 0.5 to 3 wt. %, based on the total weight of the composition.

[0104] In addition, lubricating particle additives can be added, preferably to component (A). Some examples of suitable lubricating particle additives are glycerides, waxes, and other polymers. Specifically, polytetrafluoroethylene, synthetic linear hydrocarbons, polyethylene, polypropylene, and combinations thereof are suitable lubricating particle additives. Most preferred is polytetrafluoroethylene, especially micronized polytetrafluoroethylene. In a preferred embodiment, the lubricating particle additive is present in an amount of 0.1 to 5% by weight, more preferably 0.5 to 3% by weight, based on the total weight of the composition.

[0105] In a preferred embodiment, the two-component (2K) composition comprises: (A) a first component comprising: a) at least one silicone epoxy resin, and b) optionally, at least one elastomer-modified epoxy resin; The first component contains; (B) a second component comprising: c) a curing agent consisting of at least one compound having at least two epoxide reactive groups per molecule, characterized in that the curing agent comprises at least one alkoxy-containing amino-functional silicone resin. The second component includes wherein said composition does not contain a catalyst, the molar ratio of epoxide reactive groups:epoxide groups provided by said curing agent c) is 1.5:1 to 1:1.5, preferably 1.1:1 to 1:1.1, more preferably 1:1, and further characterized in that it further comprises a trialkoxy-functional silicone prepolymer, a lubricant particle additive and / or a diluent in component (A).

[0106] In an even more preferred embodiment, the two-component (2K) composition comprises: A) a first component, based on the total weight of the first component, 10 to 60% by weight of a) said at least one silicone epoxy resin a); 1 to 40% by weight of b) at least one elastomer-modified epoxy resin b); The first component includes B) a second component comprising: c) a curing agent consisting of at least one compound having at least two epoxide reactive groups per molecule, characterized in that the curing agent comprises at least one alkoxy-containing amino-functional silicone resin. A second component comprising, preferably consisting of, wherein the composition does not contain a catalyst, the molar ratio of epoxide-reactive groups:epoxide groups provided by the curing agent c) is from 1.5:1 to 1:1.5, preferably from 1.1:1 to 1:1.1, more preferably 1:1, and the composition further comprises the following in component (A): Each based on the total amount of the composition - 0.5 to 5% by weight of at least one diluent, preferably a silanol, - 0.1 to 5% by weight of at least one trialkoxy-functional silicone prepolymer, preferably a trimethoxysilicone prepolymer, and / or - 0.1 to 5% by weight of at least one lubricating particle additive, preferably polytetrafluoroethylene The present invention is characterized by comprising:

[0107] Methods and Uses For two-component (2K) curable compositions, the reactive components are mixed together in such a way as to induce their curing: the reactive compounds should be mixed under sufficient shear to obtain a homogeneous mixture. It is believed that this can be accomplished without special conditions or special equipment. However, suitable mixing equipment includes: static mixers; magnetic stirrer equipment; wire whisks; augers; batch mixers; planetary mixers; CW Brabender or Banburry® style mixers; and high shear mixers such as blade blenders and rotary impellers.

[0108] For small-scale liner applications, where volumes of less than 2 liters are generally used, the preferred packaging of the two-component (2K) composition is a side-by-side double cartridge or a coaxial cartridge, in which two tubular chambers are arranged next to or inside each other and sealed with pistons: the actuation of these pistons allows the components to be pushed out of the cartridge, advantageously through closely mounted static or dynamic mixers. For larger volume applications, the two components of the composition can be advantageously stored in drums or buckets, where they are pushed out through a hydraulic press, in particular through a driven plate, and fed through a pipeline to a mixing device, which allows a fine and homogeneous mixing of the hardener component and the binder component. In any case, it is important that in any packaging, the binder component is arranged in an air-tight and moisture-proof seal, allowing both components to be stored for a long period of time (ideally more than 12 months).

[0109] Non-limiting examples of dual component dispensing devices and methods that may be suitable for the present invention include those described in US Pat. No. 6,129,244 and US Pat. No. 8,313,006.

[0110] Two-component (2K) curable compositions should broadly be formulated to exhibit an initial viscosity (measured immediately after mixing, e.g. within 2 minutes after mixing) of less than 200000 mPa·s, such as less than 100000 mPa·s, at 25° C. Independently of, or in addition to, said viscosity characteristics, two-component (2K) compositions should be formulated such that no air bubbles (foam) form upon mixing and subsequent curing. Furthermore, two-component (2K) compositions should be formulated to exhibit at least one, preferably at least two, and most preferably all of the following properties: i) a long pot life, typically at least 25 minutes, usually at least 60 or 120 minutes, where pot life is understood to be the time until the viscosity of the mixture at 20° C. rises to 50,000 mPas or more; ii) a maximum exotherm temperature of 120° C. or less, preferably 100° C. or less, more preferably 80° C. or less; and iii) after curing, a Shore A hardness of at least 50, preferably 60, more preferably at least 70 after storage for 7 days at room temperature and 50% relative humidity.

[0111] Curing of the compositions of the invention may take place at temperatures ranging from -10°C to 120°C, preferably from 0°C to 70°C, in particular from 20°C to 60°C. The appropriate temperature depends on the particular compounds present and the desired rate of curing and can be determined in each individual case by the skilled artisan using simple preliminary tests, if necessary. Of course, curing at temperatures of 10°C to 35°C or 20°C to 30°C is particularly advantageous, since it avoids the need to substantially heat or cool the mixture from the normal ambient temperature. However, where applicable, the temperature of the mixture formed from the respective components of the two-component (2K) composition may be raised above the mixing and / or application temperature using conventional means, including microwave induction.

[0112] The curable compositions according to the invention can be used in particular in the following applications: varnishes; inks; binders for fibres and / or particles; coatings for glass; coatings for mineral building materials such as lime and / or cement-bonded gypsum, gypsum-containing surfaces, fibre cement building materials and concrete; coatings and sealings for wood and wood-based materials such as plywood, fibreboard and paper; coatings for metal surfaces; coatings for asphalt and asphalt-containing pavements; coatings and sealings for various plastic surfaces; and coatings for leather and textiles.

[0113] In a particularly preferred embodiment, the composition of the present invention is applied to a substrate to produce an adherent, highly abrasion-resistant coating. The adhesive operation is often effected at room temperature, and after curing, effective abrasion resistance is obtained. Furthermore, when bonded to the surface of a mechanical structure or to a floor or pavement, the coating composition can provide corrosion protection to the surface, preventing the surface from coming into contact with compounds that adversely affect the operation or efficiency of the particular structure.

[0114] In each of the above applications, the composition can be applied by conventional application methods such as: brushing; roll coating, for example, using a four-roll applicator when the composition is solvent-free and a two-roll applicator for solvent-containing compositions; doctor blade application; printing; spraying (including, but not limited to, air-atomized spray, air-assisted spray, airless spray, and high volume low pressure spray). For use in coating and adhesive applications, it is recommended to apply a wet film thickness of about 10 to 500 μm. Applying thinner layers within this range is more economical and less likely to result in thick cured areas that may require sanding in coating applications. However, great care must be taken when applying thinner coatings or layers to avoid the formation of discontinuous cured films.

[0115] For completeness, it should be noted that the present invention does not preclude the preparation of epoxy adhesives in the form of "film adhesives." A prepolymer mixture of epoxy resin, hardener, and other desired components is applied as a coating onto a polymeric film substrate, rolled up, and stored at a temperature low enough to inhibit chemical reaction between the components. When desired, the film adhesive is removed from the cold environment, applied to metal or composite parts, the backing paper peeled off to complete the assembly, and cured in an oven or autoclave.

[0116] The following examples are illustrative of the present invention and are not intended to limit the scope of the invention in any way. EXAMPLES

[0117] In the examples, the following commercially available products were used: TIFF2024524511000003.tif97163

[0118] In the examples, the following tests were carried out. Open time: This is measured as the longest time for an adhesive bond to form after the composition is applied to a substrate at room temperature and 50% humidity. For example, if the composition is applied to a first piece of cardboard: i) after 5 seconds, another piece of cardboard is applied and still adheres to the first piece, but ii) after 6 seconds, the composition is too hard and set and a bond can be formed between the two pieces of cardboard, the open time will be 5 seconds.

[0119] Tack-free time: This was determined by applying the coating at a wet layer thickness of 75 μm at 23° C. and 50% relative humidity. A coating was considered to be tack-free if, after touching the surface with a clean, dry finger, a fingerprint was no longer observable. The tack-free time was measured using a timing device.

[0120] The remaining tests (abrasion resistance, corrosion resistance, and pencil hardness) were performed after the compositions were allowed to cure for 24 hours at room temperature.

[0121] Abrasion resistance: CS-17 wheels mounted on a standard Taber Abraser Model 5150 and each loaded with an additional 1 kg load were used to abrade the surfaces of mounted substrate strips (10 cm x 10 cm) coated with the inventive and comparative compositions described below. The specimens were first cleaned to remove any adhering particulate matter and then weighed before abrading. For completeness, the CS-17 abrasive wheels were obtained from Byk-Gardner and were reconditioned for 50 cycles against an S-11 refacing disk before each sample test. The Taber Abraser was energized to automatically count cycles and the abrasion was evaluated using the weight loss method for samples after 3000 cycles according to ASTM D4060 Standard Test Method for Abrasion Resistance of Organic Coatings by Taber Abraser. The following examples report weight loss (L, mg) as the difference in weight of the specimen before and after abrasion.

[0122] Corrosion resistance: The salt spray test is a standardized method for determining the corrosion resistance of coatings applied to metal substrates. The test was carried out in a salt spray cabinet, where salt water (5 wt.% NaCl) was sprayed onto the surface of a test panel coated with the coating composition of the present invention, and a line was drawn on the panel. The lined panel was kept in the salt fog for 500 hours, simulating a highly corrosive environment. Test parameters were used in accordance with ASTM B117 Standard Practice for the Operation of Salt Fog Apparatus.

[0123] Pencil Hardness: The hardness of the coatings and their resistance to scratching and abrasion were measured according to ASTM 3363 Standard Test Method for Film Hardness by Pencil Test.

[0124] Examples 1 to 20 The compositions of the examples are shown in Tables 1 and 2. Example 1 uses a base formulation containing binder, filler, and hardener. Examples 2-12 are formulated to improve performance by incorporating various amounts of additives, fillers, and diluents into the base formulation. Examples 13-16 are prepared by partially replacing the silicone epoxy resin of Example 12 with a modified epoxy resin. Examples 17 and 18 study the composition tolerance limits with ±5% of the hardener-binder mixing ratio. Comparative Examples 18 and 19 are carried out using DBDTL as a catalyst to study the curing characteristics of the composition.

[0125] After mixing the two parts, the open time, tack-free and dry to touch time of the resulting mixture were evaluated. After curing at room temperature for 24 hours, the coating thickness, hardness by pencil hardness test, abrasion resistance, contact angle and surface free energy were measured.

[0126] The table below describes the various parameters and their respective performance of the cured compositions. All compositions of Examples 1-12 exhibit good open times of 40-50 minutes, tack free times of 45-55 minutes, and dry to touch times of over 150 minutes at coating thicknesses ranging from 240-260 microns.

[0127] The base composition (Example 1) without all other specific additives and diluents has a very high abrasion value, high surface free energy, and relatively low contact angle. The partial addition of Additive 1 (Example 2), Additive 2 (Examples 7, 8), and diluent (Examples 5, 6) did not change the abrasion properties. However, the addition of Additive 2 in excess of 2% by weight of the total composition of Part A (Examples 3, 4) significantly increases the abrasion resistance properties.

[0128] The partial addition of diluent (Examples 5, 6) and Additive 1 only (Examples 7, 8) significantly increased the contact angle and decreased the surface free energy of the base composition (Example 1).

[0129] In Examples 9-12, Additive 1 and diluent are included in the base formulation with different weight ratios of Additive 2. Increasing the amount of Additive 2 along with Additive 1 and diluent improves performance by decreasing the amount of wear, increasing the contact angle, and decreasing the surface free energy. Thus, Example 12 shows better performance.

[0130] Some of the important properties such as abrasion resistance, impact resistance, contact angle and surface free energy can be significantly improved by modifying the Example 12 composition with a modified epoxy resin as a co-binder in Part A. As seen in Examples 13-16, partial replacement of the silicone epoxy resin with an epoxy resin in the composition of Example 12 further improves the performance of the composition in terms of abrasion resistance, contact angle and surface free energy along with significantly improved impact resistance. The performance improvement is observed with the addition of the epoxy resin as it further enhances the phase separation of the additives and diluents and imparts flexibility to the composition.

[0131] Examples 1-18 are cured without the use of a catalyst and show good open times of over 40 minutes, and tack-free times typically over 45 minutes. However, the catalyzed (DBTDL) cured compositions (Comparative Examples 19 and 20) show very short open times of 25 minutes, with tack-free times of less than 25 minutes. Also, the touch dry time is negatively affected by the presence of the catalyst. Additionally, the coating thickness of the catalyzed cured compositions (Comparative Examples 19 and 20) increases as the catalyst promotes a faster reaction, which causes the viscosity of the formulation to increase rapidly after mixing the two components, resulting in a thicker coating thickness when compared to the non-catalyzed composition, which shows a thickness of 240-260 microns. The faster cure also impacts the performance of the coating, i.e., increased abrasion values, decreased impact resistance, and increased surface free energy due to rapid cure and poor mechanical properties.

[0132] Examples 13-18 achieve a pencil hardness of 9H. These catalyst-free compositions have very high abrasion resistance (i.e., weight loss of less than 30 mg even after 3000 cycles of abrasion with a CS-17 Taber Abraser wheel and a 1 kg load). However, on the other hand, catalyst-based compositions (19 and 20) give much higher weight loss (i.e., >50 mg) in the same test.

[0133] [Table 1]

[0134] [Table 2]

Claims

1. Component (A) which is a first component and comprises the following: a) at least one silicone resin containing an epoxy functional group, and b) optionally, at least one elastomer-modified epoxy resin as the first component; Component (B) which is a second component and comprises the following: c) a curing agent comprising at least one compound having at least two epoxide-reactive groups per molecule, said curing agent being characterized by comprising at least one alkoxy-containing amino-functional silicone resin as the second component A two-component (2K) composition comprising the above, said composition being catalyst-free, and the molar ratio of epoxide-reactive groups:epoxide groups provided by said curing agent c) being 1.5:1 to 1:1.5, preferably 1.1:1 to 1:1.1, more preferably 1:

1. A two-component (2K) composition is provided.

2. A) Based on the weight of the first component, the following: 10 to 60% by weight of a) said at least one silicone epoxy resin a); 1 to 40% by weight of b) at least one elastomer-modified epoxy resin b); as the first component, B) The following: c) a curing agent comprising at least one compound having at least two epoxide-reactive groups per molecule, said curing agent being characterized by comprising at least one alkoxy-containing amino-functional silicone resin as the second component, preferably consisting of this The two-component composition according to claim 1, comprising the above, wherein said composition is catalyst-free, and the molar ratio of epoxide-reactive groups:epoxide groups provided by said curing agent c) is 1.5:1 to 1:1.5, preferably 1.1:1 to 1:1.1, more preferably 1:

1. The two-component composition according to claim 1 is provided.

3. The silicone resin containing an epoxy functional group has an epoxy equivalent in the range of 100 to 1500 g / eq, preferably in the range of 200 to 1000 g / eq, more preferably in the range of 300 to 700 g / eq. The two-component composition according to claim 1 is provided.

4. Said elastomer-modified epoxy resin b) has an epoxide equivalent of 200 to 2500 g / eq, preferably 200 to 500 g / eq. The two-component composition according to claim 1 is provided.

5. The at least one elastomer-functionalized epoxy resin b) comprises at least one dimer acid-modified epoxy resin or consists of at least one dimer acid-modified epoxy resin, the two-component composition according to claim 1.

6. The at least one dimer acid-modified epoxy resin is obtained as a product of a catalytic addition reaction of an epoxide compound and a C36-C44 aliphatic diacid, the two-component composition according to claim 5.

7. The curing agent c) is as follows: 90 to 100 mol% of the alkoxy-containing amino-functional silicone resin; 0 to 10 mol% of a secondary epoxy-reactive compound comprising the two-component composition according to claim 1.

8. The alkoxy-containing amino-functional silicone resin is as follows: i) an amine hydrogen equivalent of 100 to 1500 g / eq; and ii) a weight average molecular weight (Mw) of 150 to 10000 g / mol as measured by gel permeation chromatography characterizing at least one of the two-component compositions according to claim 1.

9. The curing agent c) has at least two amine hydrogen atoms per molecule, has an amine hydrogen equivalent of 100 to 1500 g / eq., and has a total alkoxy content (AC) of 10 to 40 mol% based on the number of moles of silicon, and comprises or consists of at least one alkoxy-containing amino-functional silicone resin (C1), and the resin (C1) comprises the following units: 【Chemical 1】 Here, each R is independently selected from a C1-C18 alkyl group, a C6-C18 aryl group, or an amino-functional hydrocarbon group having the formula -R2NHR3 or -R2NHR2NHR3, each R2 is independently a C2-C20 alkylene group, and R3 is a C1-C6 alkyl group; a, b, c, and d each define the molar fraction of each of the units (i) to (iv) such that a + b + c + d = 1; and w, x, y, and z define the molar fraction of the alkoxy groups such that 0 ≦ w < 1, 0 ≦ x < 2, 0 ≦ y < 3, and 0 ≦ z < 4, the two-component composition according to claim 1.

10. In the resin (C1), each R is independently selected from a C1-C6 alkyl group, a C6-C18 aryl group, or an amino-functional hydrocarbon group having the formula -R1NHR2 or -R1NHR1NHR2, where each R1 is independently a C2-C8 alkylene group and R2 is a C1-C2 alkyl group, the two-component composition according to claim 9.

11. The two-component composition according to claim 9, wherein the amino-functional silicone resin (C1) has both methyl substitution and phenyl substitution at R.

12. The amino-functional silicone resin (C1) has an a value of 0 to 0.10, b has a value of 0.15 to 0.6, c satisfies the condition 0 < c < 0.85, and d has a value of 0 to 0.05, the two-component composition according to claim 9.

13. The two-component composition according to claim 1, further comprising a trialkoxy-functional silicone prepolymer, a lubricating particle additive, and / or a diluent, preferably in component (A).

14. A cured product obtained from the two-component (2K) composition according to any one of claims 1 to 13.

15. Use of the cured reaction product according to claim 14 as a coating, a sealant, or an adhesive.

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