MANNICH BASE WITH HIGH RENEWABLE CARBON CONTENT

Description

Technical area

[0001] The invention relates to Mannich bases with a high proportion of renewable carbon and their use for curing epoxy resins. State of the art

[0002] Amines are used in industry and construction, among other things, as hardeners for epoxy resin compositions. Depending on the application, properties such as good processability and rapid, trouble-free curing at ambient temperatures are required to produce products with high hardness and low brittleness, as well as a uniform surface without blushing-related cloudiness, spots, or craters.

[0003] Today, there is increasing demand for sustainable epoxy resin products, especially those with a high content of raw materials from renewable sources, i.e., epoxy resin products that are largely bio-based. This creates a need for sustainable amine hardeners. A common measure of the sustainability of chemical raw materials is the Renewable Carbon Index (RCI), which indicates the carbon content from renewable sources. It is calculated by dividing the number of carbon atoms from a renewable source by the total number of carbon atoms in the raw material.

[0004] Mannich bases are amine-containing condensation products of phenols with amines and aldehydes, particularly formaldehyde. They can be used in epoxy resin products as sole hardeners or as co-hardeners and / or accelerators. Particularly sustainable Mannich bases from the state of the art are the Mannich bases, also known as phenalkamines, in which cardanol, an alkenylphenol mixture derived from cashew nut shell oil with an RCI of 1, is used as the phenol compound. Mannich bases with a certain carbon content from renewable sources are known, for example, from US 6,262,148 or US 2017 / 0240691. However, the processability of the resulting epoxy resin products can still be improved due to their high viscosity. Description of the invention

[0005] The object of the present invention is therefore to provide a Mannich base which is suitable for curing epoxy resins at ambient temperatures and exerts a high dilution effect on the epoxy resin in order to enable good processing and a high degree of filling even at low ambient temperatures.

[0006] Surprisingly, this object is achieved with a Mannich base of formula (I) as described in claim 1. The Mannich base according to the invention contains one or more furfurylamino groups and can be prepared in a simple process, in particular by condensing a phenol with a furfurylated amine of formula (IV) and an aldehyde, in particular formaldehyde (Mannich reaction), or by transamination of existing Mannich bases, in particular those containing dimethylaminomethyl groups. The Mannich base of formula (I) has a high Renewable Carbon Index (RCI), with the furfuryl groups in particular being bio-based and—depending on the source of the primary diamine underlying the furfurylated amine—optionally also its C atoms. If the Mannich base of formula (I) is based on a phenol compound based on renewable raw materials, such as cardanol or guaiacol, the Mannich base has a particularly high RCI in the range from 0.7 to 1.

[0007] The Mannich base of formula (I) enables surprisingly low-viscosity epoxy resin products with good processability and—in the case of filled products—high filler content, requiring little or no additional thinners or solvents, thus achieving very low VOC contents. Furthermore, the Mannich base of formula (I) enables surprisingly rapid and trouble-free curing to produce high-quality epoxy resin products with high final hardness and high gloss, even at cold ambient temperatures, particularly 8°C. Furthermore, the Mannich base of formula (I) enables very low-odor epoxy resin products, whereas the Mannich base 2,4,6-tris(dimethylaminomethyl)phenol, which is frequently used in the state of the art, results in an epoxy resin product with a strong, unpleasant amine odor, even when used in small quantities.

[0008] The Mannich base of formula (I) is particularly suitable as a hardener and / or accelerator for epoxy resin products, especially coatings or molded articles. In particular, the Mannich base of formula (I) enables low-odor coatings that cure quickly and reliably at ambient temperatures, producing beautiful, glossy surfaces without blushing-related spots, cloudiness, or craters.

[0009] Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of the dependent claims. Ways to implement the invention

[0010] The invention relates to a Mannich base of formula (I), where X represents H or a linear hydrocarbon radical having 15 C atoms, Y independently of one another in each case represents a radical of the formula (II) or H or dimethylaminomethyl or methoxy, where at least one of the radicals Y represents a radical of the formula (II), R 1< represents H or an alkyl radical having 1 to 6 C atoms or a phenyl radical, and A represents an alkylene radical having 2 to 10 C atoms, where the two nitrogen atoms to which the radical A is bonded are separated from one another by at least two C atoms.

[0011] A dashed line in the formulas in this document represents the bond between a substituent and the corresponding molecular residue.

[0012] The "RCI" refers to the "Renewable Carbon Index" of a substance or mixture of substances, where the RCI stands for the ratio of the number of C atoms from bio-based sources to the total number of C atoms of the substance or mixture of substances.

[0013] A "primary amino group" is an amino group that is bonded to a single organic residue and carries two hydrogen atoms; a "secondary amino group" is an amino group that is bonded to two organic residues, which may also be part of a ring, and carries one hydrogen atom; and a "tertiary amino group" is an amino group that is bonded to three organic residues, which may also be part of one or more rings in twos or threes, and does not carry a hydrogen atom.

[0014] The hydrogen atoms of primary and secondary amine groups are called "amine hydrogen".

[0015] The "amine hydrogen equivalent weight" is the mass of an amine or amine-containing composition containing one molar equivalent of amine hydrogen. It is expressed in the unit "g / eq."

[0016] The "epoxide equivalent weight" is the mass of an epoxy-containing compound or composition that contains one molar equivalent of epoxy groups. It is expressed in the unit "g / eq."

[0017] Substance names beginning with "poly", such as polyamine or polyepoxide, refer to substances that formally contain two or more of the functional groups mentioned in their name per molecule.

[0018] A "thinner" is a substance that is soluble in an epoxy resin and reduces its viscosity, but is not chemically bound into the epoxy resin polymer during curing.

[0019] "Molecular weight" refers to the molar mass (in grams per mole) of a molecule. "Mean molecular weight" refers to the number average M n of a polydisperse mixture of oligomeric or polymeric molecules, which is usually determined by gel permeation chromatography (GPC) against polystyrene as a standard.

[0020] Pot life is the maximum period of time from the mixing of the components and the application of an epoxy resin composition during which the mixed composition is in a sufficiently flowable state and can wet the substrate surfaces well.

[0021] The term "gel time" refers to the time from the mixing of the components of an epoxy resin composition until they gel.

[0022] A temperature of 23 °C is referred to as “room temperature”.

[0023] All industry standards and norms mentioned in this document refer to the versions valid at the time of filing the initial application, unless otherwise stated.

[0024] Weight percentages (wt%) refer to the mass fraction of a component of a composition relative to the total composition, unless otherwise stated. The terms "mass" and "weight" are used synonymously in this document.

[0025] Preferably, R 1< is H. Such Mannich bases are derived from formaldehyde or an oligomer or polymer of formaldehyde. They are particularly easy to produce and enable particularly low-viscosity epoxy resin products with particularly rapid curing. Furthermore, formaldehyde is readily available from biobased sources.

[0026] Preferably, A represents 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,3-butylene, 1,4-butylene, 2,2-dimethyl-1,3-propylene, 1,3-pentylene, 1,5-pentylene, 2-methyl-1,5-pentylene, 1,6-hexylene, 1,7-heptylene, 1,8-octylene, 1,9-nonylene, 2,2(4),4-trimethyl-1,6-hexylene or 1,10-decylene.

[0027] A particularly preferably represents a linear alkylene radical having 2 to 6 carbon atoms, i.e., 1,2-ethylene, 1,3-propylene, 1,4-butylene, 1,5-pentylene, or 1,6-hexylene, especially 1,2-ethylene. These Mannich bases are particularly readily available with high RCI and enable particularly low-viscosity epoxy resin products with particularly rapid curing.

[0028] Most preferably, A stands for 1,2-ethylene. These Mannich bases, regardless of the amine source, have a particularly high RCI and enable particularly low-viscosity epoxy resin products with particularly rapid curing.

[0029] In a preferred embodiment of the invention, X represents a linear hydrocarbon radical having 15 C atoms, the radical Y para to X represents a radical of the formula (II), the other radicals Y represent H and the Mannich base thus has the formula (Ia), where A and R 1< have the meanings already mentioned.

[0030] The Mannich base of formula (Ia) is derived from cardanol, an alkenylphenol mixture obtained from cashew nut shell oil, and exhibits a particularly high RCI. It is also referred to as phenalkamine. X represents a linear C 15 H 31 - or C 15 H 29 - or C 15 H 27 - or C 15 H 25 -hydrocarbon radical, in particular the radicals of the formulae or In particular, A stands for 1,2-ethylene and R 1< for H and the Mannich base thus has the formula Such a Mannich base is particularly sustainable and enables particularly low-viscosity epoxy resin products with particularly rapid curing. In particular, it exhibits an RCI in the range of 0.9 to 1.

[0031] Such a Mannich base is in particular a reaction product from the condensation of at least one phenol compound of formula (III) with at least one amine of formula (IV) and at least one aldehyde of formula (V), where X represents a linear hydrocarbon radical with 15 C atoms and A and R 1< have the meanings already mentioned.

[0032] Preferably, the phenol compound of formula (III) and the amine of formula (IV) are initially introduced, and the aldehyde of formula (V) is slowly added, preferably maintaining the temperature of the reaction mixture in the range of 50 to 150 °C. Subsequently, the released water and any solvent present are distilled off.

[0033] At least one mole of amine of formula (IV) and at least one mole of aldehyde of formula (V) are preferably used per mole of phenol compound of formula (III). Particular preference is given to using 1 to 10 moles, in particular 1 to 5 moles, of amine of formula (IV) and approximately 1 mole of aldehyde of formula (V) per mole of phenol compound of formula (III). This produces a reaction product with a high content of Mannich base of formula (Ia) and, if appropriate, excess amine of formula (IV). Such a reaction product has a particularly low viscosity.

[0034] The phenol compound of formula (III) is, in particular, cardanol, an alkenylphenol mixture obtained from cashew nut shell oil, where X has the meanings already mentioned. Technical-grade or, in particular, distilled and optionally further purified grades of cardanol are suitable. Commercially available grades are particularly suitable, such as Cardolite grades NX-2021, NX-2022, NX-2023, Ultra LITE 2023, NX-2024, NX-2025, or NX-2026 (all from Cardolite).

[0035] In a further preferred embodiment of the invention, X is H, a radical Y ortho to the phenol group is methoxy, the two further radicals Y each represent a radical of the formula (II) and the Mannich base thus has the formula (Ib), where R 1< and A have the meanings already described.

[0036] Such a Mannich base exhibits a particularly high RCI and enables low-viscosity epoxy resin products with particularly rapid curing. The RCI is preferably in the range of 0.8 to 1.

[0037] The Mannich bases of formula (Ib) are derived from guaiacol (o-methoxyphenol) as a phenol compound of formula (III). They are, in particular, a reaction product from the condensation of guaiacol with at least one amine of formula (IV) and at least one aldehyde of formula (V).

[0038] Bio-based guaiacol is preferred.

[0039] The preparation is preferably carried out as already described for the reaction with cardanol, wherein at least two moles of amine of formula (IV) and at least two moles of aldehyde of formula (V) are preferably used per mole of guaiacol. Particularly preferably, 2 to 10 moles, in particular 2 to 5 moles, of amine of formula (IV) and approximately 2 moles of aldehyde of formula (V) are used per mole of guaiacol. This produces a reaction product with a high content of Mannich base of formula (Ib) and optionally excess amine of formula (IV).

[0040] In a further preferred embodiment of the invention, in the Mannich base of the formula (I), X is H, all radicals Y are each a radical of the formula (II) and the Mannich base thus has the formula (Ic), where R 1< and A have the meanings already mentioned.

[0041] A Mannich base of formula (Ic) enables particularly high final hardnesses.

[0042] Preferably, R 1< represents H and A represents 1,2-ethylene, and the Mannich base of formula (Ic) is thus 2,4,6-tris((2-furfurylaminoethyl)aminomethyl)phenol. It enables epoxy resin products with particularly rapid curing and moderate viscosity. The RCI of 2,4,6-tris((2-furfurylaminoethyl)aminomethyl)phenol is preferably in the range from 0.5 to 1, in particular 0.5 to 0.6.

[0043] A Mannich base of formula (Ic) is derived from phenol as a phenol compound of formula (III). It is, in particular, a reaction product from the condensation of phenol with at least one amine of formula (IV) and at least one aldehyde of formula (V).

[0044] The preparation is preferably carried out as already described for the reaction with cardanol, wherein at least three moles of amine of formula (IV) and at least three moles of aldehyde of formula (V) are preferably used per mole of phenol.

[0045] Particularly preferably, 3 to 10 mol, in particular 3 to 5 mol, of amine of formula (IV) and approximately 3 mol of aldehyde of formula (V) are used per mole of phenol. This results in a reaction product with a high content of Mannich base of formula (Ic) and, if appropriate, excess amine of formula (IV).

[0046] Suitable amines of formula (IV) for the preparation of a Mannich base of formula (I) are reaction products from the reductive alkylation of primary diamines of formula H 2 NA-NH 2 with furfural and hydrogen. Such reaction products typically contain by-products, in particular moieties with a hydrogenated furan ring and / or dialkylated moieties, in particular as shown in the following formulas: Accordingly, the Mannich base of formula (I), or of formula (Ia), (Ib) or (Ic), may contain portions of furan ring hydrogenated on the residue of formula (II).

[0047] Particularly preferred as an amine of formula (IV) is N-furfuryl-1,2-ethanediamine, in particular with an RCI in the range of 0.7 to 1.

[0048] Suitable aldehydes of formula (V) for the preparation of a Mannich base of formula (I) are, in particular, formaldehyde, acetaldehyde, propanal, or benzaldehyde, optionally in the form of an oligomer or polymer. Formaldehyde, optionally in the form of 1,3,5-trioxane or paraformaldehyde, is particularly suitable. Formaldehyde from a bio-based source is preferred.

[0049] In a further preferred embodiment of the invention, in the Mannich base of formula (I), X is H, one or two Y radicals are a radical of formula (II) where R 1< = H, and the remaining Y radicals are each dimethylaminomethyl. Such a Mannich base of formula (I) is obtained in particular from the incomplete transamination of 2,4,6-tris(dimethylaminomethyl)phenol with at least one amine of formula (IV) with release of dimethylamine.

[0050] In a preferred embodiment of the invention, a Mannich base of the formula (Ic) with R 1< = H or a Mannich base of the formula (I) in which X is H, one or two radicals Y are a radical of the formula (II) with R 1< = H and the remaining radicals Y are each dimethylaminomethyl, is a reaction product from the transamination of 2,4,6-tris(dimethylaminomethyl)phenol with at least one amine of the formula (IV) with release and removal of dimethylamine.

[0051] Preferably, 2,4,6-tris(dimethylaminomethyl)phenol is mixed with the amine of formula (IV) and heated at a temperature in the range of 80 to 160 °C with distillative removal of dimethylamine.

[0052] Preferably, 1 to 10 mol of amine of formula (IV) are used per mol of 2,4,6-tris(dimethylaminomethyl)phenol.

[0053] Particularly preferably, 3 to 10 mol, in particular 3 to 5 mol, of amine of formula (IV) are used per mole of 2,4,6-tris(dimethylaminomethyl)phenol. This mainly results in the Mannich base of formula (Ic).

[0054] If more than 3 mol of amine of formula (IV) are used for the transamination, the reaction product may contain excess amine of formula (IV). Such a reaction product has a particularly low viscosity and can be used as such for curing epoxy resins. However, it can also be purified by removing excess amine of formula (IV) by distillation.

[0055] In the event that the transamination was only carried out incompletely, for example by using less than 3 mol of amine of formula (IV) per mole of 2,4,6-tris(dimethylaminomethyl)phenol, or by not carrying out the reaction to completion, Mannich bases of formula (I) are formed in which one or two radicals Y stand for dimethylaminomethyl.

[0056] The 2,4,6-tris(dimethylaminomethyl)phenol used for the transamination is in turn obtained in particular from the condensation of phenol with

[0057] Dimethylamine and formaldehyde. This reaction is particularly simple and produces a product of particularly high purity. 2,4,6-Tris-(dimethylaminomethyl)phenol is commercially available, for example as Ancamine®< K54 (from Evonik) or Accelerator 960-1 (from Huntsman).

[0058] Suitable amines of formula (IV) are the previously described reaction products from the reductive alkylation of primary diamines of formula H 2 NA-NH 2 with furfural and hydrogen. Accordingly, such a Mannich base can also contain portions of the furan ring hydrogenated on the residue of formula (II).

[0059] In a preferred embodiment, in the transamination of 2,4,6-tris(dimethylaminomethyl)phenol with at least one amine of the formula (IV), a polyetherdiamine, in particular a polyoxypropylenediamine having an average molecular weight M n in the range from 200 to 500 g / mol, is additionally used.

[0060] Preferably, approximately two moles of amine of formula (IV) and 0.3 to 0.7 moles of polyetherdiamine are used per mole of 2,4,6-tris(dimethylaminomethyl)phenol. In particular, a reaction product is obtained which, in addition to at least one Mannich base of formula (I), contains further Mannich bases, in particular also Mannich bases of formula (VI), where two of the radicals Z represent a radical of the formula (II) with R 1< = H and the third radical Z represents a radical of the formula (VII), B represents a divalent polyether radical, in particular polyoxypropylene with an average molecular weight M n in the range from 170 to 470 g / mol, M represents H or a radical of the formula (VIIIa) or (VIIIb), and A has the meanings already described.

[0061] Such a mixture of Mannich bases is particularly low-viscosity and polymeric, which facilitates handling and reduces volatility.

[0062] The invention further provides a hardener for epoxy resins comprising at least one Mannich base of formula (I), as described above. The hardener preferably contains 1 to 95% by weight, more preferably 2 to 80% by weight, particularly preferably 3 to 60% by weight, in particular 3 to 30% by weight, of Mannich bases of formula (I).

[0063] The hardener preferably contains at least one further component selected from further amines which do not correspond to formula (I), accelerators and diluents, in particular at least one further amine which does not correspond to formula (I).

[0064] A particularly preferred further amine not corresponding to formula (I) is an amine of formula (IV), as described above, in particular N-furfuryl-1,2-ethanediamine. Such a hardener has a high RCI and enables particularly low-viscosity epoxy resin products with rapid and trouble-free curing.

[0065] The hardener preferably contains amines of the formula (IV) and Mannich bases of the formula (I) in a weight ratio in the range from 5 / 95 to 99 / 1, preferably 10 / 90 to 98 / 2, particularly preferably 25 / 75 to 95 / 5, in particular 50 / 50 to 95 / 5.

[0066] As a further amine which does not correspond to formula (I), particularly preferred is at least one amine with a high RCI, in particular selected from 2,5-bis(aminomethyl)furan, 2,5-bis(aminomethyl)tetrahydrofuran, bis(5-aminomethylfuran-2-yl)methane, bis(5-aminomethyltetrahydrofuran-2-yl)methane, 2,2-bis(5-aminomethylfuran-2-yl)propane and 2,2-bis(5-aminomethyltetrahydrofuran-2-yl)propane.

[0067] Other suitable amines which do not correspond to formula (I) are, in particular, amines having aliphatic amino groups and at least three amine hydrogens, in particular N-benzyl-1,2-ethanediamine, N-benzyl-1,2-propanediamine, N-benzyl-1,3-bis(aminomethyl)benzene, N-(2-ethylhexyl)-1,3-bis(aminomethyl)benzene, 2,2-dimethyl-1,3-propanediamine, 1,3-pentanediamine (DAMP), 1,5-pentanediamine, 1,5-diamino-2-methylpentane (MPMD), 2-butyl-2-ethyl-1,5-pentanediamine (C11-neodiamine), 1,6-hexanediamine, 2,5-dimethyl-1,6-hexanediamine, 2,2(4),4-trimethyl-1,6-hexanediamine (TMD), 1,7-Heptanediamine, 1,8-Octanediamine, 1,9-Nonanediamine, 1,10-Decanediamine, 1,11-Undecanediamine, 1,12-Dodecanediamine, 1,2-, 1,3- or 1,4-Diaminocyclohexane, 1,3-Bis(aminomethyl)cyclohexane, 1,4-Bis(aminomethyl)cyclohexane, Bis(4-aminocyclohexyl)methane, Bis(4-amino-3-methylcyclohexyl)methane, Bis(4-amino-3-ethylcyclohexyl)methane, Bis(4-amino-3,5-dimethylcyclohexyl)methane, Bis(4-amino-3-ethyl-5-methylcyclohexyl)methane,1-Amino-3-aminomethyl-3,5,5-trimethylcyclohexane (IPDA), 2(4)-methyl-1,3-diaminocyclohexane, 2,5(2,6)-bis(aminomethyl)bicyclo[2.2.1]heptane (NBDA), 3(4),8(9)-bis(aminomethyl)tricyclo[5.2.1.0 2,6< ]decane, 1,4-diamino-2,2,6-trimethylcyclohexane (TMCDA), 1,8-menthanediamine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,3-bis(aminomethyl)benzene (MXDA), 1,4-bis(aminomethyl)benzene, Bis(2-aminoethyl)ether, 3,6-dioxaoctane-1,8-diamine, 4,7-Dioxadecane-1,10-diamine, 4,7-Dioxadecane-2,9-diamine, 4,9-Dioxadodecane-1,12-diamine, 5,8-Dioxadodecane-3,10-diamine, 4,7,10-Trioxatridecane-1,13-diamine or higher oligomers of these diamines, bis(3-aminopropyl)polytetrahydrofurans or other polytetrahydrofurandiamines, polyoxyalkylenedi- or triamines, especially polyoxypropylenediamines or polyoxypropylenetriamines such as Jeffamine®< D-230, Jeffamine®< D-400 or Jeffamine®< T-403 (all from Huntsman), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA),Pentaethylenehexamine (PEHA), dipropylenetriamine (DPTA), N-(2-aminoethyl)-1,3-propanediamine (N3-amine), N,N'-bis(3-aminopropyl)-ethylenediamine (N4-amine), N,N'-bis(3-aminopropyl)-1,4-diaminobutane, N5-(3-aminopropyl)-2-methyl-1,5-pentanediamine, N3-(3-aminopentyl)-1,3-pentanediamine, N5-(3-amino-1-ethylpropyl)-2-methyl-1,5-pentanediamine, N,N'-bis(3-amino-1-ethylpropyl)-2-methyl-1,5-pentanediamine, 3-(2-Aminoethyl)aminopropylamine, Bis(hexamethylene)triamine (BHMT), N-Aminoethylpiperazine, 3-(3-(Dimethylamino)propyl-amino)propylamine (DMAPAPA), amine-functional adducts of the above-mentioned amines with epoxides, phenalkamines, which are reaction products of cardanol with aldehydes, in particular formaldehyde, and polyamines, or a mixture of two or more of these amines.

[0068] Of these, preference is given to N-benzyl-1,2-ethanediamine, MPMD, TMD, 1,2-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, bis(4-aminocyclohexyl)methane, IPDA, 2(4)-methyl-1,3-diaminocyclohexane, MXDA, DETA, TETA, TEPA, N3-amine, N4-amine, DPTA, BHMT, polyoxypropylenediamines having an average molecular weight M n in the range from 200 to 500 g / mol or polyoxypropylenetriamines having an average molecular weight M n in the range from 300 to 500 g / mol.

[0069] 1,3-bis(aminomethyl)cyclohexane is particularly preferred. This enables particularly rapid curing.

[0070] IPDA is also particularly preferred. This achieves particularly high glass transition temperatures, enabling particularly good robustness to high service temperatures. IPDA with a high RCI made from bio-based acetone is particularly preferred.

[0071] MXDA remains particularly preferred, achieving high curing rates and particularly high strengths.

[0072] N-benzyl-1,2-ethanediamine is also particularly preferred. This allows epoxy resin products to be produced with particularly attractive surfaces.

[0073] Suitable accelerators are, in particular, acids or compounds hydrolyzable to acids, in particular organic carboxylic acids such as acetic acid, benzoic acid, salicylic acid, 2-nitrobenzoic acid, lactic acid, organic sulfonic acids such as methanesulfonic acid, p-toluenesulfonic acid or 4-dodecylbenzenesulfonic acid, sulfonic acid esters, other organic or inorganic acids such as, in particular, phosphoric acid, or mixtures of the aforementioned acids and acid esters; nitrates such as, in particular, calcium nitrate; tertiary amines such as in particular 1,4-diazabicyclo[2.2.2]octane, benzyldimethylamine, α-methylbenzyldimethylamine, triethanolamine, dimethylaminopropylamine, imidazoles such as in particular N-methylimidazole, N-vinylimidazole or 1,2-dimethylimidazole, salts of such tertiary amines, quaternary ammonium salts such as in particular benzyltrimethylammonium chloride, amidines such as in particular 1,8-diazabicyclo[5.4.0]-undec-7-ene, guanidines such as in particular 1,1,3,3-tetramethylguanidine, phenols, in particular bisphenols, phenol resins or other Mannich bases such as in particular 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol or polymers of phenol, formaldehyde and N,N-dimethyl-1,3-propanediamine, phosphites such as in particular di- or triphenyl phosphites, or compounds containing mercapto groups.

[0074] Preferred accelerators are acids, nitrates, tertiary amines or other Mannich bases, in particular salicylic acid, calcium nitrate or 2,4,6-tris(dimethylaminomethyl)phenol, or a combination of these accelerators.

[0075] Suitable thinners are in particular n-propanol, isopropanol, n-butanol, isobutanol, tert.Butanol, 1-Pentanol, 2-Pentanol, 3-Pentanol, 2-Methyl-1-butanol, 3-Methyl-1-butanol, 3-Methyl-2-butanol n-Hexanol, 2-Ethylhexanol, Xylol, 2-Methoxyethanol, Dimethoxyethanol, 2-Ethoxyethanol, 2-Propoxyethanol, 2-Isopropoxyethanol, 2-Butoxyethanol, 2-Phenoxyethanol, 2-Benzyloxyethanol, Benzylalkohol, Ethylenglykol, Ethylenglykoldimethylether, Ethylenglykoldiethylether, Ethylenglykoldibutylether, Ethylenglykoldiphenylether, Diethylenglykol, Diethylenglykolmonomethylether, Diethylenglykolmonoethylether, Diethylenglykolmono-n-butylether, Diethylenglykoldimethylether, Diethylenglykoldiethylether, Diethylenglykoldi-n-butylylether, Propylenglykolbutylether, Propylenglykolphenylether, Dipropylenglykol, Dipropylenglykolmonomethylether, Dipropylenglykoldimethylether, Dipropylenglykoldi-n-butylether, 2,2,4-Trimethyl-1,3-pentandiolmonoisobutyrat, Diphenylmethan, Diisopropylnaphthalin, Erdölfraktionen wie zum Beispiel Solvesso ®< -Typen (von Exxon), Alkylphenole wie tert.Butylphenol, nonylphenol, dodecylphenol, cardanol, styrenated phenol, bisphenols, aromatic hydrocarbon resins, in particular types containing phenol groups, alkoxylated phenol, in particular ethoxylated or propoxylated phenol, in particular 2-phenoxyethanol, adipates, sebacates, phthalates, benzoates, organic phosphoric or sulfonic acid esters or sulfonamides.

[0076] Preferred among these are thinners with a boiling point above 200 °C, especially benzyl alcohol, styrenated phenol, ethoxylated phenol, aromatic hydrocarbon resins containing phenol groups, such as the Novares® types LS 500, LX 200, LA 300, or LA 700 (from Rütgers), diisopropylnaphthalene, or cardanol, especially benzyl alcohol. Phenol-containing thinners also act as accelerators. Also preferred are aromatic thinners with a particularly high diluting effect, especially xylene.

[0077] Of these, thinners with an RCI of 1, especially Cardanol, are particularly preferred. These enable a particularly sustainable hardener.

[0078] The hardener preferably contains only a small amount of thinner, in particular 0 to 50% by weight, preferably 0 to 30% by weight, of thinner based on the total hardener.

[0079] The hardener may be water-based and contain water in the range of 15 to 90% by weight, preferably 20 to 80% by weight.

[0080] The hardener is preferably non-water-based. It preferably contains less than 15% by weight, in particular less than 10% by weight, of water, based on the total hardener. Such a hardener is particularly suitable for non-aqueous epoxy resins. It enables epoxy resin products with particularly high resistance to moisture.

[0081] The hardener may contain other ingredients, in particular: amine-functional adducts with epoxides, monoamines such as in particular benzylamine or furfurylamine, amines with two amine hydrogens, in particular N,N'-difurfuryl-1,2-ethanediamine, N,N'-dibenzyl-1,2-ethanediamine or 3-dimethylaminopropylamine (DMAPA), polyamidoamines, in particular reaction products of a mono- or polybasic carboxylic acid or its ester or anhydride, in particular a dimer fatty acid, with a polyamine used in stoichiometric excess, in particular DETA or TETA, aromatic polyamines such as in particular 4,4'-, 2,4' and / or 2,2'-diaminodiphenylmethane, 2,4(6)-toluenediamine, 3,5-dimethylthio-2,4(6)-toluenediamine or 3,5-diethyl-2,4(6)-toluenediamine, compounds containing mercapto groups, in particular liquid Mercaptan-terminated polysulfide polymers, mercaptan-terminated polyoxyalkylene ethers, mercaptan-terminated polyoxyalkylene derivatives, polyesters of thiocarboxylic acids, 2,4,6-trimercapto-1,3,5-triazine, triethylene glycol dimercaptan or ethanedithiol,surface-active additives, in particular defoamers, deaerators, wetting agents, dispersants or leveling agents, or stabilizers, in particular stabilizers against oxidation, heat, light or UV radiation.

[0082] Another object of the invention is an epoxy resin composition comprising a resin component comprising at least one epoxy resin and a hardener component comprising at least one Mannich base of formula (I), as previously described.

[0083] A suitable epoxy resin is obtained in a known manner, in particular from the reaction of epichlorohydrin with polyols, polyphenols or amines.

[0084] Suitable epoxy resins are in particular aromatic epoxy resins, in particular the glycidyl ethers of: Bisphenol A, bisphenol F or bisphenol A / F, where A stands for acetone and F for formaldehyde, which served as starting materials for the production of these bisphenols. In the case of bisphenol F, positional isomers may also be present, in particular derived from 2,4'- or 2,2'-hydroxyphenylmethane, dihydroxybenzene derivatives such as resorcinol, hydroquinone or pyrocatechol; other bisphenols or polyphenols such as bis(4-hydroxy-3-methylphenyl)methane, 2,2-bis(4-hydroxy-3-methylphenyl)propane (bisphenol C), bis(3,5-dimethyl-4-hydroxyphenyl)methane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxy-3-tert.butylphenyl) propane, 2,2-bis(4-hydroxyphenyl)butane (bisphenol-B), 3,3-bis(4-hydroxyphenyl)pentane, 3,4-bis(4-hydroxyphenyl)hexane, 4,4-bis(4-hydroxyphenyl)heptane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 2,4-Bis(3,5-dimethyl-4-hydroxyphenyl)-2-methylbutane, 1,1-Bis(4-hydroxyphenyl)cyclohexane (Bisphenol-Z), 1,1-Bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (Bisphenol-TMC), 1,1-Bis(4-hydroxyphenyl)-1-phenylethane, 1,4-Bis[2-(4-hydroxyphenyl)-2-propyl]-benzene (Bisphenol-P), 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene (bisphenol-M), 4,4'-dihydroxydiphenyl (DOD), 4,4'-dihydroxybenzophenone, bis(2-hydroxy-naphth-1-yl)methane, bis(4-hydroxynaphth-1-yl)methane, 1,5-dihydroxynaphthalene, tris(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, bis(4-hydroxyphenyl)ether or bis(4-hydroxyphenyl)sulfone; novolaks, which are in particular condensation products of phenol or cresols with formaldehyde orParaformaldehyde or acetaldehyde or crotonaldehyde or isobutyraldehyde or 2-ethylhexanal or benzaldehyde or furfural; aromatic amines such as aniline, toluidine, 4-aminophenol, 4,4'-methylenediphenyldiamine, 4,4'-methylenediphenyldi-(N-methyl)amine, 4,4'-[1,4-phenylenebis(1-methylethylidene)]bisaniline (bisaniline-P) or 4,4'-[1,3-phenylenebis(1-methylethylidene)]bisaniline (bisaniline-M).

[0085] Other suitable epoxy resins are aliphatic or cycloaliphatic polyepoxides, in particular Glycidyl ethers of saturated or unsaturated, branched or unbranched, cyclic or open-chain di-, tri- or tetrafunctional C 2 - to C 30 -alcohols, in particular ethylene glycol, propylene glycol, butylene glycol, hexanediol, octanediol, polypropylene glycols, dimethylolcyclohexane, neopentyl glycol, dibromoneopentyl glycol, castor oil, trimethylolpropane, trimethylolethane, pentaerythrol, sorbitol or glycerol, or alkoxylated glycerol or alkoxylated trimethylolpropane; a hydrogenated bisphenol A, F or A / F liquid resin, or the glycidylation products of hydrogenated bisphenol A, F or A / F; an N-glycidyl derivative of amides or heterocyclic nitrogen bases, such as triglycidyl cyanurate or triglycidyl isocyanurate, or reaction products of epichlorohydrin with hydantoin.

[0086] Other suitable epoxy resins are epoxy resins with a high RCI, especially those resulting from the reaction of bio-based hydroxy-functional raw materials with bio-based epichlorohydrin. Vanillin-based epoxy resins, such as vanillin alcohol diglycidyl ethers or the glycidyl ethers of bisvanillin derivatives, as well as glycerol-based epoxy resins, such as the glycidyl ethers of glycerol or polyglycerol, are particularly preferred.

[0087] Preferably, the epoxy resin is a liquid resin or a mixture containing two or more epoxy liquid resins.

[0088] An "epoxy liquid resin" is a technical polyepoxide with a glass transition temperature below 25 °C.

[0089] If necessary, the resin component also contains portions of solid epoxy resin.

[0090] The epoxy resin is in particular a liquid resin based on a bisphenol or novolak, in particular with an average epoxy equivalent weight in the range of 156 to 210 g / eq.

[0091] Bisphenol A diglycidyl ether and / or bisphenol F diglycidyl ether, such as those commercially available from Olin, Huntsman, or Momentive, are particularly suitable. These liquid resins have a low viscosity for an epoxy resin and enable rapid curing and high hardness. They can contain portions of bisphenol A solid resin or novolak epoxy resins.

[0092] Particularly preferred is a bisphenol A diglycidyl ether with an RCI of 0.3 from the reaction of bisphenol A with bio-based epichlorohydrin.

[0093] Also particularly preferred are phenol-formaldehyde novolak glycidyl ethers, in particular with an average functionality in the range from 2.3 to 4, preferably 2.5 to 3. They may contain proportions of other epoxy resins, in particular bisphenol A diglycidyl ether or bisphenol F diglycidyl ether.

[0094] Also particularly preferred are epoxy resins with a high RCI, in particular vanillin alcohol diglycidyl ether or the glycidyl ethers of glycerol or polyglycerol.

[0095] The resin component may contain a reactive diluent.

[0096] Preferred reactive diluents are reactive diluents containing epoxy groups, in particular butanediol diglycidyl ether, hexanediol diglycidyl ether, trimethylolpropane di- or triglycidyl ether, phenyl glycidyl ether, cresyl glycidyl ether, guaiacol glycidyl ether, 4-methoxyphenyl glycidyl ether, pn-butylphenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, 4-nonylphenyl glycidyl ether, 4-dodecylphenyl glycidyl ether, cardanol glycidyl ether, benzyl glycidyl ether, allyl glycidyl ether, butyl glycidyl ether, hexyl glycidyl ether, 2-ethylhexyl glycidyl ether, or glycidyl ethers of natural alcohols such as in particular C 8 to C 10 or C 12 to C 14 or C 13 to C 15 alkyl glycidyl ethers.

[0097] The epoxy resin composition preferably contains at least one epoxy resin with an RCI in the range of 0.2 to 1, in particular 0.5 to 1. This enables particularly sustainable epoxy resin products.

[0098] Preferably, the hardener component of the epoxy resin composition comprises a hardener containing at least one Mannich base of formula (I), as described above.

[0099] In particular, the hardener component additionally comprises at least one amine of formula (IV), as described above.

[0100] The epoxy resin composition preferably contains at least one further component selected from the group consisting of thinners, accelerators, fillers, pigments and surface-active additives.

[0101] The ones already mentioned are particularly suitable as thinners or accelerators.

[0102] Suitable fillers include, in particular, ground or precipitated calcium carbonate, optionally coated with fatty acids, especially stearates, barite (barite), talc, quartz flour, quartz sand, silicon carbide, micaceous iron oxide, dolomite, wollastonite, kaolin, mica (potassium aluminum silicate), molecular sieves, aluminum oxide, zinc oxide, aluminum-doped zinc oxide, aluminum hydroxide, magnesium hydroxide, silica, cement, gypsum, fly ash, carbon black, graphite, metal powders such as aluminum, copper, iron, zinc, silver, or steel, PVC powder or hollow spheres, as well as bio-based fillers such as lignin powder or ground nutshells or fruit stones. Preferred fillers are calcium carbonate, barite, quartz flour, talc, aluminum powder, bio-based fillers, or a combination thereof.

[0103] Suitable pigments include, in particular, titanium dioxide, iron oxide, chromium(III) oxide, organic pigments, carbon black, or anticorrosive pigments, especially phosphates, orthophosphates, or polyphosphates, which contain, in particular, chromium, zinc, aluminum, calcium, strontium, or a combination of these metals as counterions. Titanium dioxide is particularly suitable.

[0104] Suitable surface-active additives are, in particular, defoamers, deaerators, wetting agents, dispersants, leveling agents and / or dispersed paraffin waxes.

[0105] The epoxy resin composition may contain other auxiliaries and additives, in particular the following: Reactive diluents, in particular those already mentioned, or epoxidized soybean oil or linseed oil, compounds containing acetoacetate groups, in particular acetoacetylated polyols, butyrolactone, carbonates, aldehydes, isocyanates or silicones containing reactive groups; polymers, in particular polyamides, polysulfides, polyvinyl formal (PVF), polyvinyl butyral (PVB), polyurethanes (PUR), polymers with carboxyl groups, polyamides, butadiene-acrylonitrile copolymers, styrene-acrylonitrile copolymers, butadiene-styrene copolymers, homo- or copolymers of unsaturated monomers, in particular from the group comprising ethylene, propylene, butylene, isobutylene, isoprene, vinyl acetate or alkyl (meth)acrylates, in particular chlorosulfonated polyethylenes or fluorine-containing polymers or sulfonamide-modified melamines; Fibers, in particular glass fibers, carbon fibers, metal fibers, ceramic fibers, plastic fibers such as polyamide fibers or polyethylene fibers or bio-based fibers such as wood fibers,Cellulose fibers, hemp fibers, flax (linen), jute or coconut fibers; nanofillers, in particular carbon nanotubes; rheology modifiers, in particular thickeners or anti-settling agents; adhesion promoters, in particular organoalkoxysilanes; flame-retardant substances, in particular the fillers already mentioned: aluminium hydroxide or magnesium hydroxide, antimony trioxide, antimony pentoxide, boric acid (B(OH)3), zinc borate, zinc phosphate, melamine borate, melamine cyanurate, ammonium polyphosphate, melamine phosphate, melamine pyrophosphate, polybrominated diphenyl oxides or diphenyl ethers, phosphates such as in particular diphenyl cresyl phosphate, resorcinol bis(diphenyl phosphate), resorcinol diphosphate oligomer, tetraphenylresorcinol diphosphite, ethylenediamine diphosphate, bisphenol A bis(diphenyl phosphate), tris(chloroethyl)phosphate, tris(chloropropyl)phosphate, tris(dichloroisopropyl)phosphate, tris[3-bromo-2,2-bis(bromomethyl)propyl]phosphate, tetrabromobisphenol A, bis(2,3-dibromopropyl ether) of bisphenol A,brominated epoxy resins, ethylene bis(tetrabromophthalimide), ethylene bis(dibromonorbornane dicarboximide), 1,2-bis(tribromophenoxy)ethane, tris(2,3-dibromopropyl)isocyanurate, tribromophenol, hexabromocyclododecane, bis(hexachlorocyclopentadieno)cyclooctane or chlorinated paraffins; or stabilizers against oxidation, heat, light or UV radiation or biocides.

[0106] The epoxy resin composition preferably contains only a low content of thinners. It preferably contains less than 20% by weight, more preferably less than 10% by weight, especially less than 5% by weight, and most preferably less than 1% by weight of thinner.

[0107] The epoxy resin composition may contain water.

[0108] In one embodiment, the epoxy resin composition is water-based. The epoxy resin is preferably emulsified in water in an amount of 50 to 85% by weight, and the hardener component preferably contains 20 to 80% by weight of water.

[0109] The epoxy resin composition preferably contains only a low water content, preferably less than 5% by weight, in particular less than 1% by weight. Such a non-water-based epoxy resin composition is particularly versatile and particularly water-resistant.

[0110] Preferably, an epoxy resin composition comprising a resin component containing at least one epoxy resin and optionally further components such as, in particular, reactive diluents containing epoxy groups, thinners, fillers, pigments and / or surface-active additives, and a hardener component containing at least one Mannich base of the formula (I) and optionally further components such as, in particular, further amines, accelerators and / or thinners.

[0111] The resin and hardener components of the epoxy resin composition are stored in separate containers.

[0112] A suitable container for storing the resin or hardener components is, in particular, a drum, a hobbock, a bag, a bucket, a can, a cartridge, or a tube. The components are storable, meaning they can be stored for several months up to a year or longer before use without their respective properties changing to an extent relevant to their intended use.

[0113] The resin and hardener components are mixed shortly before or during application. The mixing ratio is preferably selected such that the molar ratio of the groups reactive toward epoxy groups to the epoxy groups is in the range of 0.5 to 1.5, particularly 0.7 to 1.2. In parts by weight, the mixing ratio between the resin and hardener components is typically in the range of 1:2 to 20:1.

[0114] The components are mixed continuously or batchwise using a suitable process, ensuring that there is not too much time between mixing the components and application and that application occurs within the pot life. Mixing and application can take place at ambient temperature, which is typically in the range of about 5 to 40°C, preferably about 10 to 35°C, or at elevated temperature, in particular in the range of 40 to 150°C, preferably 50 to 120°C.

[0115] With the mixing of the components, the curing of the epoxy resin composition begins through a chemical reaction. Primary and secondary amino groups, and any other epoxy-reactive groups present, react with the epoxy groups, causing their ring opening. Furthermore, the Mannich base of formula (I) catalyzes the homopolymerization of the epoxy groups. As a result primarily of these reactions, the composition polymerizes and thus cures.

[0116] Curing typically takes several hours to days. The duration depends, among other things, on the temperature, the reactivity of the components, their stoichiometry, and the presence or amount of accelerators.

[0117] In the freshly mixed state, the epoxy resin composition has a low viscosity. The viscosity 5 minutes after mixing the resin and hardener components at 20°C is preferably in the range of 0.1 to 20 Pa s, preferably 0.2 to 10 Pa s, particularly preferably 0.25 to 5 Pa s, measured using a cone-and-plate viscometer at a shear rate of 10 s -1< .

[0118] The epoxy resin composition is applied to at least one substrate and / or into at least one casting mold.

[0119] Particularly suitable substrates are: Glass, glass ceramics, concrete, mortar, cement screed, fiber cement, brick, tile, plaster or natural stones such as granite or marble; repair or leveling compounds based on PCC (polymer-modified cement mortar) or ECC (epoxy resin-modified cement mortar); metals or alloys such as aluminum, iron, steel, copper, other non-ferrous metals, including surface-treated metals or alloys such as galvanized or chrome-plated metals; asphalt or bitumen; leather, textiles, paper, wood, wood materials bonded with resins, for example phenolic, melamine or epoxy resins, resin-textile composites or other so-called polymer composites; Plastics such as rigid and soft PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resins, phenolic resins, PUR, POM, TPO, PE, PP, EPM or EPDM, each untreated or surface-treated, for example by means of plasma, corona or flames;Fiber-reinforced plastics, such as carbon fiber-reinforced plastics (CFRP), glass fiber-reinforced plastics (GRP), natural fiber-reinforced plastics (NFRP) and sheet molding compounds (SMC); insulating foams, in particular made of EPS, XPS, PUR, PIR, rock wool, glass wool or foamed glass (foam glass); coated or painted substrates, in particular painted tiles, painted concrete, powder-coated metals or alloys or painted sheets; coatings, paints or varnishes, in particular coated floors which are covered with another floor covering layer.

[0120] If necessary, the substrates may be pretreated before application, in particular by physical and / or chemical cleaning processes or the application of an activator or a primer.

[0121] The substrates are in particular coated and / or glued.

[0122] A suitable casting mold is a device into which the mixed, liquid epoxy resin composition can be poured and cured therein and, after curing, can be demolded or removed therefrom, whereby the cured composition forms a molded body.

[0123] The casting mold preferably consists, at least on the surface, of a material from which the cured epoxy resin composition can be removed again without damage, in particular of metal, ceramic, plastic or silicone, which may optionally be provided with a non-stick coating, in particular of Teflon, silicone or a wax.

[0124] Another object of the invention is a cured composition obtained from the described epoxy resin composition after mixing the resin and hardener components.

[0125] The epoxy resin composition is preferably used as a coating, primer, adhesive, sealant, potting compound, casting resin, impregnating resin, or as a molded body or matrix for composite materials such as, in particular, CFRP (containing carbon fibers), GFRP (containing glass fibers), NFRP (containing natural fibers) or wood composite materials.

[0126] The use results in an article containing the cured composition of the described epoxy resin composition.

[0127] The article is in particular a floor coating, wall coating, component coating, pipe coating, roof coating or a corrosion protection coating, or a bonded article, or a shaped body, in particular a composite material. Examples

[0128] The following are exemplary embodiments intended to illustrate the described invention in more detail. Of course, the invention is not limited to these described exemplary embodiments.

[0129] "AHEW" stands for amine hydrogen equivalent weight.

[0130] "EEW" stands for epoxy equivalent weight.

[0131] The "standard climate" ("NK") is defined as a temperature of 23±1°C and a relative humidity of 50±5%.

[0132] Unless otherwise stated, the chemicals used were from Sigma-Aldrich Chemie GmbH. Description of the measurement methods:

[0133] The viscosity was measured on a thermostatted Rheotec RC30 cone-and-plate viscometer (cone diameter 50 mm, cone angle 1°, cone tip-to-plate distance 0.05 mm, shear rate 10 s -1< ). Viscosities of less than 100 mPa s were measured at a shear rate of 100 s -1<.

[0134] The Amine number was determined by titration (with 0.1N HClO 4 in acetic acid against crystal violet).

[0135] Gas chromatograms (GC) were measured in the temperature range from 60 to 320 °C with a heating rate of 15 °C / min and a residence time of 10 min at 320 °C. The injector temperature was 250 °C. A Zebron ZB-5 column was used (L = 30 m, ID = 0.25 mm, dj = 0.5 µm) at a gas flow of 1.5 ml / min. Detection was performed by flame ionization (FID).

[0136] 1< H-NMR spectra were measured on a Bruker Ascend 400 spectrometer at 400.14 MHz; chemical shifts δ are given in ppm relative to tetramethylsilane (TMS). True and pseudo-coupling patterns were not distinguished. Substances and abbreviations used:

[0137] Ancamine ®< K54: 2,4,6-Tris(dimethylaminomethyl)phenol (from Evonik) Jeffamine ®< D-230: Polyoxypropylenediamine, average molecular weight 230 g / mol, AHEW 60 g / eq (from Huntsman) F-EDA: N-Furfuryl-1,2-ethanediamine, AHEW 46.7 g / eq, RCI 0.71, prepared as described below B-EDA: N-Benzyl-1,2-ethanediamine, AHEW 50.1 g / eq, prepared as described below Araldite ®< GY 250: Bisphenol A diglycidyl ether, EEW approx. 187 g / eq (from Huntsman) Araldite ®< DY-E: Monoglycidyl ether of C 12 to C 14 alcohols, EEW approx. 290 g / eq (from Huntsman) Cardanol Cardolite ®< NX-2026 (from Cardolite) Production of amines: N-Furfuryl-1,2-ethanediamine (F-EDA):

[0138] 105.2 g (1.75 mol) of 1,2-ethanediamine were placed in a round-bottom flask under a nitrogen atmosphere at room temperature. A solution of 48.05 g (0.5 mol) of furfural (furan-2-carbaldehyde, RCI = 1) in 200 ml of isopropanol was added with vigorous stirring, and the mixture was stirred for 1 hour at 40 °C. A further 1,000 ml of isopropanol was added to the reaction mixture, and the mixture was then hydrogenated at a hydrogen pressure of 80 bar, a temperature of 80 °C, and a flow rate of 5 ml / min on a continuously operating hydrogenation apparatus with a Pd / C fixed-bed catalyst. To monitor the reaction, IR spectroscopy was used to check whether the imine band at approximately 1665 cm -1 had disappeared. The hydrogenated solution was then concentrated on a rotary evaporator at 65 °C, removing unreacted 1,2-ethanediamine, water and isopropanol.

[0139] 41.2 g of this reaction mixture were then distilled at 70 °C under vacuum, collecting 25.6 g of distillate at a vapor temperature of approximately 50 °C and 0.1 bar. A colorless liquid with a

[0140] Amine number of 802 mg KOH / g, an AHEW of about 46.7 g / eq, an RCI of 0.71, a viscosity of 3.2 mPa s at 20 °C and a content of N-furfuryl-1,2-ethanediamine of 94.6 wt% and N-tetrahydrofurfuryl-1,2-ethanediamine of 5.3 wt% determined by GC, which are referred to below as F-EDA was used.

[0141] 1< H-NMR (CDCl 3 ): 7.33 (d, 1 H, Ar-H), 6.27 (m, 1 H, Ar-H), 6.14 (m, 1 H, Ar-H), 3.76 (s, 2 H, Ar-CH 2 ), 2.78 (m, 2 H, NHCH 2 CH 2 ), 2.65 (m, 2 H, C H 2 NH 2 ), 1.52 (br s, 3 H, NH and NH 2 ). N-Benzyl-1,2-ethanediamine (B-EDA):

[0142] 180.3 g (3 mol) of 1,2-ethanediamine were initially charged at room temperature, mixed with a solution of 106.0 g (1 mol) of benzaldehyde in 1200 ml of isopropanol, and stirred for 2 hours. The mixture was then hydrogenated at 80 °C, 80 bar hydrogen pressure, and a flow rate of 5 ml / min on a continuously operating hydrogenation apparatus with a Pd / C fixed-bed catalyst. The hydrogenated solution was concentrated on a rotary evaporator at 65 °C, removing unreacted 1,2-ethanediamine, water, and isopropanol. The resulting reaction mixture was purified by distillation at 80 °C under vacuum. A colorless liquid was obtained with an N-benzyl-1,2-ethanediamine content of > 97%, determined by GC. Production of Mannich bases: Mannich Base B-1:

[0143] In a round-bottomed flask with an attached cold trap (filled with acetic acid 50 wt% in water, dry ice in the cold finger, cooled in an ice bath), 13.25 g (0.05 mol) of 2,4,6-tris(dimethylaminomethyl)phenol (Ancamine ®< K54, from Evonik) were placed under a nitrogen atmosphere and added with stirring with 22.03 g (0.15 mol) of N-furfuryl-1,2-ethanediamine ( F-EDA, RCI 0.71, prepared as described above). This reaction mixture was heated to 140 °C with stirring and a nitrogen stream, with released dimethylamine being collected in the cold trap. The amine number of the reaction mixture decreased within a few hours from 735 mg KOH / g to 576 mg KOH / g, after which the reaction mixture was cooled to room temperature. A yellowish-clear liquid containing 2,4,6-tris((2-furfurylaminoethyl)aminomethyl)phenol was obtained with a viscosity at 20 °C of 13.5 Pa s, an RCI of 0.5, and an estimated AHEW of approximately 92 g / eq.

[0144] An analysis by HPLC-MS showed that the Mannich base B-1 contained less than 0.5% by weight of 2,4,6-tris(dimethylaminomethyl)phenol. Mannich Base B-2:

[0145] In a round-bottomed flask with an attached cold trap (filled with acetic acid 50 wt% in water, dry ice in the cold finger, cooled in an ice bath), 13.25 g (0.05 mol) of 2,4,6-tris(dimethylaminomethyl)phenol (Ancamine ®< K54, from Evonik) were placed under a nitrogen atmosphere and added with stirring with 14.20 g (0.10 mol) of N-furfuryl-1,2-ethanediamine ( F-EDA,RCI 0.71, prepared as described above) and 6.00 g (0.025 mol) of polyoxypropylenediamine (Jeffamine®< D-230, average molecular weight 230 g / mol, from Huntsman) were added. This reaction mixture was heated to 140 °C with stirring and a nitrogen stream, with released dimethylamine being collected in the cold trap. The amine number of the reaction mixture decreased from 677 mg KOH / g to 524 mg KOH / g within a few hours, after which the reaction mixture was cooled to room temperature. A yellowish-clear liquid was obtained with a viscosity at 20 °C of 6.2 Pa s and an estimated AHEW of approximately 105 g / eq. Mannich Base B-3:

[0146] In a round-bottomed flask, 20.00 g (67 mmol) of cardanol (RCI 1) and 9.34 g (67 mmol) of N-furfuryl-1,2-ethanediamine ( F-EDA,RCI 0.71, prepared as described above) and 2.00 g (67 mmol) of paraformaldehyde were added. The reaction mixture was heated to 100 °C under nitrogen and stirred for 3 h. The volatile components were then removed from the reaction mixture in a rotary evaporator at 65 °C under vacuum. This yielded 27.2 g of a yellowish-clear liquid with an amine number of 247 mg KOH / g.

[0147] 1< H-NMR (CDCl 3 ): 7.56 (d, 1 H, Ar-H furan), 6.67 (d, 1 H, Ar-H cardanol), 6.55 (t, 2 H, Ar-H cardanol), 6.37 (m, 1 H, Ar-H furan), 6.27 (d, 1 H, Ar-H furan), 5.36 (m, 4 H, 2x CH=CH), 3.71 and 3.38 (s, 2 H, Ar(cardanol)-CH 2 -N), 3.65 (s, 2 H, Ar(furan)-CH 2 -N), 2.77 (m, 2 H, Ar(cardanol)-CH 2 -C), 2.51 (m, 4 H, NCH 2 CH 2 N), 1.99 (m, 4 H, 2x C-CH 2 -C), 1.51 (m, 2 H, 2x C-CH 2 -C), 1.27 (m, 10 H, 5x C-CH 2 -C), 0.85 (m, 3 H, CH 3 ). Mannich base R-1:

[0148] As for the Mannich base B-1As described, 13.25 g (0.05 mol) of 2,4,6-tris-(dimethylaminomethyl)phenol (Ancamine ®< K54, from Evonik) were placed under a nitrogen atmosphere and stirred with 22.50 g (0.15 mol) of N-benzyl-1,2-ethanediamine ( B-EDA, (prepared as described above). The amine number of the reaction mixture decreased from 705 mg KOH / g to 565 mg KOH / g within a few hours, after which the reaction mixture was cooled to room temperature. A yellowish-clear liquid was obtained with a viscosity at 20 °C of 44.2 Pa s and an estimated AHEW of approximately 96.7 g / eq.

[0149] The Mannich base B-1 is an example according to the invention and mainly contains a Mannich base of formula (Ic). The Mannich base B-2 is an example according to the invention and contains, in addition to a Mannich base of formula (Ic), additional Mannich bases of formula (VI). The Mannich base B-3is an example according to the invention and contains mainly a Mannich base of formula (Ia). The Mannich base R-1 is a reference example and serves as a comparison. Production of epoxy resin compositions: Examples Z-1 to Z-4 and Ref-1 to Ref-4:

[0150] For each example, the resin component ingredients listed in Tables 1 and 2 were mixed in the specified amounts (in parts by weight) using a centrifugal mixer (SpeedMixer™< DAC 150, FlackTek Inc.) and stored under exclusion of moisture.

[0151] Likewise, the ingredients of the hardener component listed in Tables 1 and 2 were processed and stored.

[0152] The two components of each composition were then processed into a homogeneous liquid using the centrifugal mixer and immediately tested as follows: viscositywas measured 5 min after mixing the resin and hardener components as described at a temperature of 20 °C.

[0153] The Setting time was determined by moving a freshly mixed amount of approximately 3 g in standard conditions with a spatula at regular intervals until the mass gelled.

[0154] The Shore D Hardness was determined according to DIN 53505 on two cylindrical test specimens (diameter 20 mm, thickness 5 mm), one stored in standard climate and one at 8 °C and 80% relative humidity, and the hardness was measured after 1 day (24 h) and after 2 days.

[0155] Furthermore, a film with a layer thickness of 500 µm was applied to a glass plate and stored and cured in a standard climate. King's hardness (Pendulum hardness according to König according to DIN EN ISO 1522) after 1 day, 2 days, 7 days and after 14 days ( 1d NK ), ( 2d NK ), ( 7d NK ), ( 14d NKAfter 14 days, the aspect ( NK ) of the film. A clear film with a glossy and non-sticky surface without any texture was considered "beautiful." "Texture" refers to any type of pattern or design on the surface.

[0156] Another film was applied to a glass plate with a layer thickness of 500 µm. Immediately after application, this film was stored for 7 days at 8 °C and 80% relative humidity and then cured for 2 weeks under standard conditions. 24 hours after application, a polypropylene bottle cap was placed on the film, underneath which a moist sponge was placed. After another 24 hours, the sponge and cap were removed and placed on a new part of the film, where they were removed and re-placed after 24 hours, a total of 4 times. The appearance of this film was then assessed (in the tables with "Aspect (8° / 80%)"(denoted), in the same way as described for aspect (NK). The number and type of visible marks caused by the damp sponge or the applied lid were also recorded. "Blushing" was the number of white stains. "(1)" denoted a faint, white stain. "1" denoted a distinct, white stain. "Ring" indicated whether a ring-shaped mark was present due to the first lid being applied 24 hours after application. Such a ring-shaped mark indicates that the coating is not yet walkable. "(yes)" denoted a very slight mark, and "yes" denoted a distinct mark due to the first lid being applied 24 hours after application. The Königs hardness was again determined on the cured films, each after 7 days at 8 °C and 80% relative humidity ( King's . (7d 8° / 80%)), then after another 2 days in the NK ( King's . (+2d NK) ) or 7 days in NK ( King's . (+7d NK) ) or 14d in the NK ( King's . (+14d NK) ).

[0157] The results are shown in Tables 1 and 2.

[0158] For epoxy resin compositions Z-1 until Z-4 are examples according to the invention. The epoxy resin compositions Ref-1 until Ref-4 These are comparative examples. Z-1 Z-3 Ref-1 Ref-3. Table 1: Composition and properties of to and to "nb" stands for "not determined" Example Z-1 Ref-1 Z-2 Z-3 Ref-2 Ref-3 Resin component: Araldite ®< GY-250 167.2 167.2 167.2 167.2 167.2 167.2 Araldite ®< DY-E 31.8 31.8 31.8 31.8 31.8 31.8 Hardener component: Mannichbase B-1 92.0 - - 5.0 - - Mannichbase R-1 - 96.7 - - - - Mannichbase B-2 - - 75.0 - - - F-EDA - - - 46.7 46.7 46.7 Ancamine ®< K54 - - - - - 5.0 Viscosity (10') [Pa s] 2.7 3.5 2.6 0.23 0.20 0.21 Setting time (h:min) 3:20 2:50 4:10 4:45 5:10 4:45 Shore D (1d NK) 84 79 78 72 71 78 (2d NK) 84 79 79 78 75 79 Shore D (1d 8° / 80%) 69 nb 30 13 7 40 (2d 8° / 80%) 71 nb 61 54 47 61 King's hardness [s] (1d NK) 137 197 112 66 48 88 (2d NK) 200 217 153 99 77 134 (7d NK) 218 192 148 122 169 (14d NK) 200 160 148 167 Aspect (NK) nice nice nice nice nice nice Royal St. [s] (7d 8° / 80%) 113 160 60 18 11 31 (+2d NK) 136 204 111 38 27 62 (+7d NK) 158 140 71 41 87 (+14d NK) 164 148 91 70 99 Aspect (8° / 80%) nice nice nice nice nice nice Blushing 0 0 (1) 1 1 1 ring no no no (Yes) Yes (Yes) Z-4 Ref-4 Table 2: Composition and properties of and Example Z-4 Ref-4 Resin component: Araldite ®< GY-250 167.2 167.2 Araldite ®< DY-E 31.8 31.8 Hardener component: F-EDA 35.0 46.7 Mannichbase B-2 56.5 - Cardanol - 38.0 Viscosity (10') [Pa s] 0.37 0.32 King's hardness [s] (7d NK) 20 18 (14d NK) 42 20 Aspect (NK) nice nice Royal St. (7d 8° / 80%) 6 1 (+7d NK) 24 5 (+14d NK) 43 7 Aspect (8° / 80%) nice nice Blushing 0 0 ring Yes Yes

Claims

1. Mannich base of the formula (I): where X is H or a linear hydrocarbyl radical having 15 carbon atoms, Y is in each case independently a radical of the formula (II) or H or dimethylaminoethyl or methoxy, where at least one of the Y radicals is a radical of the formula (II), R1 is H or an alkyl radical having 1 to 6 carbon atoms or a phenyl radical, and A is an alkylene radical having 2 to 10 carbon atoms, where the two nitrogen atoms to which the A radical is bonded are separated from one another by at least two carbon atoms.

2. Mannich base according to Claim 1, characterized in that R1 is H.

3. Mannich base according to either of Claims 1 and 2, characterized in that A is a linear alkyl radical having 2 to 6 carbon atoms, especially 1,2-ethylene.

4. Mannich base according to any of Claims 1 to 3, characterized in that X is a linear hydrocarbyl radical having 15 carbon atoms, the Y radical para to X is a radical of the formula (II), the other Y radicals are H, and the Mannich base thus has the formula (Ia):

5. Mannich base according to any of Claims 1 to 3, characterized in that X is H, one Y radical ortho to the phenol group is methoxy, the other two Y radicals are each a radical of the formula (II), and the Mannich base thus has the formula (Ib):

6. Mannich base according to any of Claims 1 to 3, characterized in that X is H, all three Y radicals are a radical of the formula (II), and the Mannich base thus has the formula (Ic):

7. Mannich base according to any of Claims 1 to 3, characterized in that X is H, one or two Y radicals are a radical of the formula (II) with R1 = H, and the other Y radicals are each dimethylaminomethyl.

8. Mannich base according to either of Claims 6 and 7, characterized in that it is a reaction product from the transamination of 2,4,6-tris(dimethylaminomethyl)phenol with at least one amine of the formula (IV) by release and removal of dimethylamine, where R1 in formula (Ic) is H.

9. Mannich base according to Claim 8, characterized in that, in the transamination of 2,4,6-tris(dimethylaminomethyl)phenol with at least one amine of the formula (IV), a polyetherdiamine is additionally used, especially a polyoxypropylenediamine having an average molecular weight Mn in the range from 200 to 500 g / mol.

10. Curing agent for epoxy resins, containing at least one Mannich base according to any of Claims 1 to 9.

11. Curing agent according to Claim 10, characterized in that it includes at least one further constituent selected from further amines that do not conform to the formula (I), accelerators and thinners, in particular at least one further amine that does not conform to the formula (I).

12. Curing agent according to Claim 11, characterized in that the further amine included that does not conform to the formula (I) is at least one amine of the formula (IV): where A is an alkylene radical having 2 to 10 carbon atoms, where the two nitrogen atoms to which the A radical is bonded are separated from one another by at least two carbon atoms.

13. Epoxy resin composition comprising - a resin component comprising at least one epoxy resin and - a curing agent component comprising at least one Mannich base according to any of Claims 1 to 9.

14. Epoxy resin composition according to Claim 13, characterized in that the curing agent component comprises the curing agent according to any of Claims 10 to 12.

15. Cured epoxy resin composition obtained from the epoxy resin composition according to either of Claims 13 and 14 after the resin component and the curing agent component have been mixed.