Novel ether-amine compositions and their use as hardeners for epoxy resins

Abstract

The present invention relates to compositions of ether-amines having a high proportion of terminal alkylamine units of the formula-CH (CH3)-CH2-NH2, the preparation of such compositions of ether-amines and curable compositions comprising epoxy resins and such compositions of ether-amines as curing agents. The invention further relates to the curing of such a curable composition and to the resulting cured epoxy resin. These ether-amine compositions are characterized by combining comparatively high reactivity with good early water resistance even at low temperatures and enabling cured epoxy resins to have good mechanical and thermal properties. Thus, these compositions are particularly suitable for industrial coating, such as marine coating or flooring.

Description

[0001] The present invention relates to compositions of ether - amines having a high proportion of terminal alkylamine units of the formula - CH(CH3)-CH2-NH2, to the preparation of such compositions of ether - amines, and to curable compositions comprising an epoxy resin and such an ether - amine as a curing agent. The present invention further relates to the curing of such curable compositions and to the resulting cured epoxy resins.

[0002] Epoxy resins are well - known and are used as materials for surface coating, as adhesives, and for molding and laminating, as well as for the production of fiber - reinforced composites due to their toughness, flexibility, adhesion, and chemical resistance.

[0003] Typical curing agents for epoxy resins are polyamines that cause a polyaddition reaction (chain extension). Polyamines with high reactivity are usually added only shortly before the desired curing. Thus, such systems are so - called two - component (2K) systems.

[0004] An important application of epoxy resins is surface coating and especially floor coating (flooring). This application requires a curing agent that allows rapid curing even at low temperatures. The coating should be load - able (walk - able for floor coatings) as quickly as possible after application to the surface, i.e., have sufficient hardness (e.g., Shore D hardness). A high glass transition temperature of the coating is also an important criterion so that the coating remains stable at high service temperatures. Good early water resistance is also important for coatings on surfaces exposed to moisture (e.g., outdoor floor coatings).

[0005] Polyetheramines such as D230 or D400 are commonly known curing agents for epoxy resins in various applications such as coating, flooring, adhesives, and electrical potting applications (Ullmann's Encyclopedia of Industrial Chemistry, Wiley - VCH, Weinheim, Germany, 2012, Volume 13, Epoxy Resins, H. Pham and M. Marks (online: 15.10.2005, DOI: 10.1002 / 14356007.a09_547.pub2)). Polyetheramines based on propylene oxide such as D230 or D400 exhibits low viscosity and vapor pressure, and they allow low temperature curing of epoxy resins. They provide strong, clear and impact-resistant cured epoxy resins, which makes them particularly suitable for coating, casting and adhesive applications. They also exhibit a low tendency for surface blushing (water-induced urethane formation), which is also beneficial for coating applications such as flooring (Burton et al., "Epoxy Formulations using Polyetheramines [Use Epoxy formulations of polyetheramines]"; technical brochure, published on 27 April 2005).

[0006] The disadvantage of these generally known propylene oxide-based polyetheramines is their low reactivity, which leads to slow curing rates, especially for low temperature curing. To overcome this problem, these polyetheramines are typically combined with accelerators (e.g., phenolic compounds or tertiary amines) or other more reactive primary amines acting as co-curing agents. However, such additional components generally have a negative impact on the mechanical properties of the cured epoxy resin, and many of these additional compounds are harmful volatile organic compounds that make handling problematic. On the other hand, known polyetheramines that do not have alkyl side chains, such as 4,9-dioxadodecane-1,12-diamine (DODA) and 4,7,10-trioxatridecane-1,13-diamine (TTD), exhibit higher reactivity and allow faster epoxy resin curing, but their production is expensive and they are quite hygroscopic, which is disadvantageous in the context of coating applications.

[0007] There is a need for amine curing agents for curing epoxy resins, in particular for coating applications such as floor coverings and also for adhesives, which combine the advantages of the known propylene oxide-based polyetheramines with a high reactivity and a fast curing rate even without the addition of accelerators or other amines. In addition to the higher reactivity, such novel amine curing agents should have a very similar property profile so that they can be used as direct replacements for these known propylene oxide-based polyetheramines in established applications.

[0008] The object of the present invention may therefore be regarded as providing an amine curing agent suitable for curing epoxy resins particularly for coating applications such as flooring, industrial coatings or marine coatings and also for adhesives, which amine curing agent converts known propylene oxide based polyetheramines such as D230 or The advantages of D400 are combined with higher reactivity and curing rate (especially for curing at low temperatures). This higher reactivity is particularly advantageous for use in combination with other highly reactive amine curing agents such as isophorone diamine.

[0009] Accordingly, the present invention relates to providing a hardener composition comprising an ether-amine composition consisting of one or more ether-amines having the formula I

[0010]

[0011] wherein A is -CH(CH3)-CH2- or -CH2-CH(CH3)-, and

[0012] each X is independently -CH(CH3)-CH2-NH2 or -CH2-CH(CH3)-NH2, and

[0013] n ≥ 0,

[0014] characterized in that at least 30 mol-% of all X in the ether-amine composition is -CH(CH3)-CH2-NH2.

[0015] Conventionally known propylene oxide-based polyetheramines such as D230 or D400 are represented by formula I-a

[0016]

[0017] wherein A is -CH(CH3)-CH2- or -CH2-CH(CH3)-, and wherein n ≥ 0.

[0018] Substantially all of the aminated terminal propylene oxide units of these polyetheramines are -CH2-CH(CH3)-NH2 groups, where the methyl side chain is directly adjacent to the amino group.

[0019] In contrast, the ether-amine composition of the present invention is a mixture of ether-amines having the following formula: formula I-a

[0020]

[0021] formula I-b

[0022]

[0023] formula I-c

[0024]

[0025] wherein A is -CH(CH3)-CH2- or -CH2-CH(CH3)-, and wherein n ≥ 0,

[0026] The prerequisite is that at least 30 mol-% of all aminated terminal propylene oxide units (-CH(CH3)-CH2-NH2 groups or -CH2-CH(CH3)-NH2 groups) of the ether-amine in this mixture are -CH(CH3)-CH2-NH2 groups. Compared with known propylene oxide-based polyetheramines such as D230 or D400, these aminated terminal propylene oxide units have a reverse orientation such that the methyl side chain is not connected to the carbon adjacent to the amino group. For this reason, the ether-amine composition of the present invention is also referred to herein as "reverse-phase polyetheramine".

[0027] In a specific embodiment of the present invention, such a mixture (ether-amine composition) only contains ether-amines having the formula I-b and / or I-c.

[0028] Preferably, the ether-amine composition of the present invention is characterized in that at least 40 mol-%, more preferably at least 50 mol-%, and particularly preferably at least 60 mol-% of all aminated terminal propylene oxide units X in the ether-amine composition are -CH(CH3)-CH2-NH2. The ratio of the two different terminal alkylamine units -CH(CH3)-CH2-NH2 and -CH2-CH(CH3)-NH2 can be determined, for example, by 1 H-NMR or 13 C-NMR attached proton test (APT).

[0029] The ether-amine of the ether-amine composition is characterized in that the value of n ≥ 0, for example, in the range of 0 to 1000. Preferably, the ether-amine of the ether-amine composition is characterized in that the value of n ≥ 1, for example, in the range of 1 to 100, more preferably 1 to 20. The ether-amine composition of the present invention is usually a mixture of ether-amines with different n values. In this case, the value is the number average value of n of all ether-amines having the above formula I. For example, a mixture (ether-amine composition) of 50 mol-% of ether-amine having the formula I-c (where n = 1) and 50 mol-% of ether-amine having the formula I-c (where n = 2) has the number average value. According to the following formula, the n value corresponds to the molecular weight M (M EA )

[0030] M EA = (132 + n * 58) g / mol.

[0031] According to the following formula, the value corresponds to the average molecular weight of the corresponding ether-amine composition

[0032]

[0033] of the ether-amine composition is preferably in the range of 1 to 40, more preferably in the range of 1 to 10. The average molecular weight of the ether-amine composition is preferably in the range of 190 to 2450 g / mol, more preferably in the range of 190 to 700 g / mol.

[0034] The present invention further relates to a method for producing a hardener composition comprising the ether-amine composition of the present invention, the method comprising

[0035] (I) a step of preparing a corresponding polypropylene glycol composition (having the same formula as the ether-amine of the ether-amine composition but having a hydroxyl group instead of an amino group) by ring-opening polymerization of propylene oxide using water, propylene glycol or dipropylene glycol as an initiator and a non-protic Lewis acid as a catalyst, and

[0036] (II) a step of converting the polypropylene glycol composition of step (I) into the corresponding ether-amine composition of the present invention by catalytic reductive amination with hydrogen and ammonia.

[0037] The polypropylene glycol composition of step (I) corresponds to the ether-amine composition of the present invention, but has a hydroxyl group instead of an amino group. Therefore, the polypropylene glycol of such a composition is characterized by a relatively high proportion of primary hydroxyl groups, preferably at least 30 mol-%, more preferably at least 40 mol-%, particularly preferably at least 50 mol-%, especially at least 60 mol-% of all the hydroxyl groups in the polypropylene glycol composition. Such polypropylene glycol can be produced by ring-opening polymerization of propylene oxide catalyzed by a non-protic Lewis acid (US 6531566, WO 2019 / 055725, Miyajima et al., Polymer J. [Polymer Journal] (2015), 47, 771-778).

[0038] Preferred aprotic Lewis acid catalysts for step (I) of the process for producing an ether-amine composition are trifluoroborane, trifluoroaluminum, tri-organoborane compounds, tri-organoaluminum compounds, bis-organofluoroborane compounds, bis-organofluoroaluminum compounds, organodifluoroborane compounds, and organodifluoroaluminum compounds. The organo group can be an alkyl, aryl, aralkyl, or alkaryl group. The organo groups of such compounds can be the same or different. The organo groups can bear substituents, such as fluorine substituents, provided they are aprotic. Preferably, each organo group has from 1 to 20 carbon atoms, more preferably from 3 to 10 carbon atoms. The alkyl group can be straight-chain, branched, or cycloaliphatic. Preferably, they are saturated. Preferred organo groups are butyl groups, such as n-butyl, isobutyl, or preferably tert-butyl, and phenyl groups. Such butyl and phenyl groups can be unsubstituted or substituted, preferably substituted by fluorine atoms, such as pentafluorophenyl. Preferably, the aprotic Lewis acid catalyst for step (I) of the process for producing an ether-amine composition is selected from the group consisting of compounds: triphenylborane, diphenyltert-butylborane, tris(tert-butyl)borane, triphenylaluminum, diphenyltert-butylaluminum, tris(tert-butyl)aluminum, tris(pentafluorophenyl)borane, bis(pentafluorophenyl)-tert-butylborane, tris(pentafluorophenyl)aluminum, bis(pentafluorophenyl)-tert-butylaluminum, bis(pentafluorophenyl)fluoroborane, di(tert-butyl)fluoroborane, (pentafluorophenyl)difluoroborane, (tert-butyl)difluoroborane, bis(pentafluorophenyl)fluoroaluminum, di(tert-butyl)fluoroaluminum, (pentafluorophenyl)difluoroaluminum, and (tert-butyl)difluoroaluminum. Particularly preferably, these catalysts are selected from the group consisting of triphenylborane, triphenylaluminum, tris(pentafluorophenyl)borane, and tris(pentafluorophenyl)aluminum, and more preferably, these catalysts are tris(pentafluorophenyl)borane or tris(pentafluorophenyl)aluminum or a mixture thereof. These catalysts can be a single aprotic Lewis acid compound or a mixture of two or more such compounds.

[0039] Step (I) of the process for producing an ether-amine composition is preferably carried out at a temperature in the range of 50 °C to 150 °C and at a pressure in the range of 1 to 50 bar.

[0040] Step (II) of the process for producing an ether-amine composition is preferably carried out in the presence of a rather high excess of ammonia. Preferably, the molar ratio of ammonia to the hydroxyl groups of the polypropylene glycol composition is in the range from 5:1 to 100:1, more preferably in the range from 10:1 to 50:1, and particularly preferably in the range from 15:1 to 30:1. Step (II) is preferably carried out at a temperature in the range from 150 °C to 250 °C. A rather high excess of ammonia and a rather low reaction temperature are important for reducing the formation of by-products (such as the formation of secondary and tertiary amines) and thus for increasing the selectivity of the reaction. The reaction is carried out in the presence of hydrogen, preferably at a hydrogen pressure in the range from 100 to 200 bar absolute. The reaction of step (II) is carried out in the presence of a hydrogenation catalyst, preferably a heterogeneous hydrogenation catalyst. Suitable hydrogenation catalysts are based on the metals Co, Ni, Pt, Ru, Rh, Pd or mixtures thereof as active substances. The catalytically active metal can be used in elemental form (such as Raney-cobalt or Raney-nickel), or in its oxidized form (as an oxide, chloride, nitrate, such as PtO2 (Adams' catalyst)), and can be supported on a solid support, such as a solid support selected from Al2O3, ZrO2, TiO2, SiO2, activated carbon and mixtures thereof (such as Ru / C or Co / Al2O3). Both fixed-bed catalysts and suspension catalysts can be used.

[0041] During step (I) of the process for producing an ether-amine composition, dipropylene glycol (the reaction product of two propylene oxide units) is formed as part of the polypropylene glycol composition, especially if a polypropylene glycol composition with a rather low n value is prepared. Dipropylene glycol can form unwanted by-products, such as piperazine (if present during the amination of step (II)). Thus, in a preferred variant of the process for producing the ether-amine composition according to the invention, step (I) is followed by a purification step (I-a), in which at least part of the dipropylene glycol formed during step (I) (or used as an initiator) is removed from the polypropylene glycol composition of step (I) before the remaining polypropylene glycol composition is used for step (II). Preferably, this purification step (I-a) is carried out in such a way that the residual amount of dipropylene glycol in the polypropylene glycol composition is less than 10% b.w., more preferably less than 5% b.w., and most preferably less than 2% b.w. Typically, the purification step (I-a) is carried out by distillation, preferably under reduced pressure (such as in the range from 10 to 500 mbar absolute). This purification step (I-a) is preferably employed in the process for producing an ether-amine with a rather low n value or an ether-amine composition with a rather low

[0042] The hydroxyl value of the polypropylene glycol composition produced by step (I) or (I-a) of the process is preferably in the range of 10 to 1000 mg KOH / g, particularly preferably in the range of 20 to 800 mg KOH / g, very particularly preferably in the range of 40 to 600 mg KOH / g, as determined according to DIN 53240-1 (2013). The hydroxyl value is the number of mg of KOH equivalent to the hydroxyl content of 1 g of the alcohol composition. For this determination, the sample is first converted with an excess of acetic anhydride. The hydroxyl groups in the sample react with the acetic anhydride, releasing acetic acid. The remaining acetic anhydride is then cleaved with water into two molecules of acetic acid. Finally, the total amount of acetic acid formed is measured by titration with KOH. The hydroxyl value is obtained from the difference between the KOH consumption (in mg) of the control (without alcohol) and the KOH consumption of the alcohol composition to be tested (using 1 g of the alcohol composition). Based on the assumption that all compounds in the polypropylene glycol composition are diols (OH-functionality 2), according to the following formula, the average molecular weight is directly related to the hydroxyl value (HV PPG ) of the polypropylene glycol composition:

[0043]

[0044] The hydroxyl value of the polypropylene glycol composition and thus its average molecular weight can be controlled substantially by the choice of initiator (dipropylene glycol, propylene glycol or water), the ratio of initiator (dipropylene glycol, propylene glycol or water) to propylene oxide, and the use of step (I-a). Preferably, propylene glycol or dipropylene glycol is used as the initiator. Preferably, the molar ratio of initiator to propylene oxide is in the range of 1:0.1 to 1:100, particularly preferably in the range of 1:0.5 to 1:50, very particularly preferably in the range of 1:1 to 1:10.

[0045] The average molecular weight of the ether-amine composition produced by step (II) is determined substantially by the average molecular weight of the polypropylene glycol composition used in step (II) . Thus, the average molecular weight of such an ether-amine composition can be controlled substantially by controlling the average molecular weight of the polypropylene glycol composition .

[0046] The process for producing the ether-amine composition can be carried out as a continuous process or a batch process.

[0047] Accordingly, the present invention further relates to a hardener composition comprising an ether-amine composition obtainable or obtained by the process for producing an ether-amine composition according to the present invention.

[0048] The hydroxyl value (HV EA)Preferably in the range of 10 to 1000 mg KOH / g as determined according to DIN 53240-1 (2013), particularly preferably in the range of 20 to 800 mg KOH / g, and very particularly preferably in the range of 40 to 600 mg KOH / g. The hydroxyl groups as well as the primary and secondary amino groups in the sample react with acetic anhydride used for the determination of the hydroxyl value. Therefore, if this method is used for a sample that also has amino groups in addition to hydroxyl groups, the contributions of the hydroxyl groups as well as the primary and secondary amino groups to the hydroxyl value are equal.

[0049] The total amine value (AV 总计 ) (for the total amount of primary, secondary and tertiary amines) of the ether-amine composition of the present invention is preferably in the range of 10 to 1000 mg KOH / g, preferably 20 to 800 mg KOH / g, particularly preferably 40 to 600 mg KOH / g. During step (II) of the method for producing the ether-amine composition, primary amines can condense to form secondary amines and further condense to form tertiary amines as by-products. Preferably, the content of such by-products in the ether-amine composition of the present invention is low. Therefore, the amine value (AV prim ) of the primary amines of the ether-amine composition of the present invention, based on AV 总计 is preferably in the range of at least 80%, more preferably in the range of at least 90%, and particularly preferably in the range of at least 95%, and the amine value (AV sec ) of the secondary amines of the ether-amine composition of the present invention, based on AV 总计 is preferably in the range of at most 20%, more preferably in the range of at most 10%, and particularly preferably in the range of at most 5%, and the amine value (AV tert ) of the tertiary amines of the ether-amine composition of the present invention, based on AV 总计 is preferably in the range of at most 5%, more preferably in the range of at most 3%, and particularly preferably in the range of at most 1%. The amine values of the total amine, primary amine, secondary amine and tertiary amine are determined according to standard ASTM D2074 (2017).

[0050] The degree of amination (D A ) achieved by step (II) of the method for producing the ether-amine composition corresponds to the ratio of the number of amino groups to the sum of the amino groups and the remaining hydroxyl groups. Since the number of amino groups is represented by AV 总计 , and the sum of the amino groups and hydroxyl groups is represented by HV EA plus AV tert (primary and secondary amines but not tertiary amines contribute to HV EA ), therefore D A can be calculated according to the following formula:

[0051] D A = AV 总计 / (HVEA +AV tert )

[0052] This simplified formula for DA does not take into account the reduction in the number of amine groups due to the formation of secondary (and tertiary) amines.

[0053] Preferably, the D of the ether-amine composition of the present invention A is in the range of at least 0.80, more preferably in the range of at least 0.90, and particularly preferably in the range of at least 0.93.

[0054] Based on the assumption that all compounds of the ether-amine composition of the present invention have two terminal hydroxyl groups and / or primary amino groups, according to the following formula, the empirical average molecular weight of such an ether-amine composition is directly related to the corrected hydroxyl value (since not only hydroxyl and primary amino groups but also secondary amino groups contribute to the hydroxyl value (HV EA ), and this part (secondary amine value; AV sec ) must be deducted to only consider (terminal) hydroxyl and primary amino groups):

[0055]

[0056] Preferably, the empirical average molecular weight of these ether-amines is in the range of 180 to 280 g / mol, more preferably in the range of 200 to 260 g / mol or in the range of 320 to 480 g / mol, more preferably in the range of 350 to 450 g / mol, which is respectively within the range of the average molecular weight of the known conventional non-reactive polyetheramines D230 or D400.

[0057] The present invention further relates to a curable composition comprising a resin component containing at least one epoxy resin and a curing component, characterized in that the curing component is the hardener composition of the present invention.

[0058] Epoxy resins according to the present invention typically have 2 to 10, preferably 2 to 6, very particularly preferably 2 to 4, and especially 2 epoxy groups. The epoxy groups are especially glycidyl ether groups, such as those formed in the reaction of an alcohol group with epichlorohydrin. The epoxy resin may generally have an average molecular weight (M) of less than 1000 g / mol n) low molecular weight compounds, or higher molecular weight compounds (polymers). Such polymeric epoxy resins preferably have an oligomerization degree of 2 to 25, particularly preferably 2 to 10 units. The resin can be an aliphatic or cycloaliphatic compound or a compound containing aromatic groups. In particular, the epoxy resin is a compound containing two aromatic or aliphatic 6-membered rings or its oligomer. Epoxy resins obtainable by the reaction of epichlorohydrin with a compound having at least two reactive H atoms, particularly with a polyol, are of industrial importance. Epoxy resins obtainable by the reaction of epichlorohydrin with a compound containing at least two, preferably two hydroxyl groups and two aromatic or aliphatic 6-membered rings are particularly important. Such compounds particularly include bisphenol A and bisphenol F, as well as hydrogenated bisphenol A and bisphenol F - the corresponding epoxy resins are the diglycidyl ethers of bisphenol A or bisphenol F, or hydrogenated bisphenol A or bisphenol F. Preferably used as the epoxy resin according to the present invention are epoxy resins selected from the group consisting of: the diglycidyl ether of bisphenol A, the diglycidyl ether of bisphenol F, the diglycidyl ether of hydrogenated bisphenol A, and the diglycidyl ether of hydrogenated bisphenol F. Typically used as the epoxy resin according to the present invention is bisphenol A diglycidyl ether (DGEBA). Suitable epoxy resins according to the present invention also include tetraglycidyl methylene dianiline (TGMDA) and triglycidyl aminophenol or mixtures thereof. Also contemplated are the reaction products of epichlorohydrin with other phenols, such as cresol, or phenol - aldehyde adducts, such as phenol - formaldehyde resins, particularly novolacs. Epoxy resins not derived from epichlorohydrin are also suitable. Examples of the resins contemplated include epoxy resins containing epoxy groups resulting from the reaction with glycidyl (meth)acrylate. According to the present invention, an epoxy resin or a mixture thereof that is liquid at room temperature is preferably employed. The epoxy resin equivalent weight (EEW) indicates the average mass (in g) of the epoxy resin per mole of epoxy groups.

[0059] Preferably, the curable composition according to the present invention consists to some extent of at least 10% b.w., more preferably at least 30% b.w., particularly at least 50% b.w. of the epoxy resin.

[0060] The resin component may further comprise one or more reactive diluents. For the purposes of the present invention, a reactive diluent is a compound that reduces the initial viscosity of the curable composition and forms chemical bonds with the network during the curing process of the curable composition when the network is formed from the epoxy resin and the curing agent. For the purposes of the present invention, preferred reactive diluents are low molecular weight, organic, preferably aliphatic compounds having one or more epoxy groups, and also cyclic carbonates such as ethylene carbonate, vinylene carbonate or propylene carbonate. The reactive diluents of the present invention are preferably selected from the group consisting of: 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether (HDBE), glycidyl neodecanoate, glycidyl versatate, 2-ethylhexyl glycidyl ether, neopentyl glycol diglycidyl ether, p-tert-butyl glycidyl ether, butyl glycidyl ether, C8-C 10 -alkyl glycidyl ether, C 12 -C 14 -alkyl glycidyl ether, nonylphenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, phenyl glycidyl ether, o-tolyl glycidyl ether, polyoxypropylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether (TMP), glycerol triglycidyl ether, triglycidyl p-aminophenol (TGPAP), divinylbenzyl dioxide and dicyclopentadiene diepoxide. They are particularly preferably selected from the group consisting of: 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether (HDBE), 2-ethylhexyl glycidyl ether, C8-C 10 -alkyl glycidyl ether, C 12 -C 14 -alkyl glycidyl ether, neopentyl glycol diglycidyl ether, p-tert-butyl glycidyl ether, butyl glycidyl ether, nonylphenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, phenyl glycidyl ether, o-tolyl glycidyl ether, trimethylolpropane triglycidyl ether (TMP), glycerol triglycidyl ether, divinylbenzyl dioxide and dicyclopentadiene diepoxide. They are particularly selected from the group consisting of: 1,4-butanediol diglycidyl ether, C8-C 10 -alkyl monoglycidyl ether, C 12 -C 14 -alkyl monoglycidyl ether, 1,6-hexanediol diglycidyl ether (HDBE), neopentyl glycol diglycidyl ether, trimethylolpropane triglycidyl ether (TMP), glycerol triglycidyl ether, and dicyclopentadiene diepoxide.

[0061] Based on the resin component of the curable composition (epoxy resin and any reactive diluent used), the reactive diluent according to the invention preferably accounts for up to 30% b.w., particularly preferably up to 25% b.w., especially up to 20% b.w. In a specific embodiment, based on the resin component of the curable composition (epoxy resin and any reactive diluent used), the reactive diluent according to the invention accounts for at least 5% b.w., especially at least 10% b.w.

[0062] In addition to the ether-amine composition of the present invention, the hardener composition may further comprise one or more additional amine curing agents (other than the ether-amine compounds having the formula I (i.e., formula Ia, Ib or Ic)). Based on the total amount of amine curing agents in the curable composition (the ether-amine composition of the present invention and any additional amine curing agents other than the ether-amine compounds having the formula I), the ether-amine composition of the present invention preferably accounts for at least 50% b.w., particularly preferably at least 80% b.w., very particularly preferably at least 90% b.w. In a specific embodiment, in addition to the ether-amine composition of the present invention, the curable composition does not contain any additional amine curing agents. In the context of the present invention, amine curing agents should be understood to mean amines having an NH functionality of ≥2 (thus, for example, a primary monoamine has an NH functionality of 2, a primary diamine has an NH functionality of 4, and an amine having 3 secondary amino groups has an NH functionality of 3). Such additional amine curing agents may be aliphatic, cycloaliphatic or aromatic amines. Examples of such additional amine curing agents are amines selected from the group consisting of: 2,2-dimethyl-1,3-propanediamine, 1,3-pentanediamine (DAMP), 1,5-pentanediamine, 1,5-diamino-2-methylpentane (MPMD), 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 2,5-dimethyl-1,6-hexanediamine, 2,2,4- and 2,4,4-trimethylhexamethylenediamine (TMD), dimethyldicyclohexylmethane (DMDC), isophoronediamine (IPDA), methylcyclohexylenediamine (MCDA), diethylenetriamine (DETA), triethylenetetramine (TETA), aminoethylpiperazine (AEP), dimethylaminopropylamine (DMAPA), N'-(3-aminopropyl)-N,N-dimethylpropane-1,3-diamine (DMAPAPA), m-xylenediamine (MXDA), styrene-modified MXDA( 240), 1,3-bis(aminomethyl)cyclohexane (1,3-BAC), bis(p-aminocyclohexyl)methane (PACM), methylenedianiline (e.g., 4,4'-methylenedianiline), diaminodiphenylmethane (DDM), diaminodiphenylsulfone (DDS), 2,4-toluenediamine, 2,6-toluenediamine, diethyltoluenediamine (DETDA) (e.g., 2,4-diamino-3,5-diethyltoluene or 2,6-diamino-3,5-diethyltoluene, 1,2-diaminobenzene), 1,3-diaminobenzene, 1,4-diaminobenzene, diaminocyclohexane (e.g., 1,2-diaminocyclohexane (DACH)), 1,8-menthanediamine, diaminodiphenyl ether, 3,3',5,5'-tetramethyl-4,4'-diaminobiphenyl and 3,3'-dimethyl-4,4'-diaminobiphenyl, and also amino plastic resins (e.g., condensation products of aldehydes such as formaldehyde, acetaldehyde, crotonaldehyde or benzaldehyde with melamine, urea or benzoguanamine), and also mixtures thereof. Preferably, such additional amine curing agents are amines selected from the group consisting of: 2,2,4- and 2,4,4-trimethylhexamethylenediamine (TMD), dimethyldiaminodicyclohexylmethane (DMDC), isophoronediamine (IPDA), methylcyclohexyldiamine (MCDA), diethylenetriamine (DETA), triethylenetetramine (TETA), aminoethylpiperazine (AEP), m-xylenediamine (MXDA), styrene-modified MXDA( 240), 1,3-bis(aminomethyl)cyclohexane (1,3-BAC), bis(p-aminocyclohexyl)methane (PACM), diaminocyclohexane (e.g., 1,2-diaminocyclohexane (DACH)), and mixtures thereof.

[0063] In the curable composition of the present invention, the epoxy compound (epoxy resin and any reactive diluent having its respective reactive group) of the resin component and the amine curing agent (ether-amine composition and any additional amine curing agent) of the curing component are preferably used in an approximate equivalent ratio based on the epoxy equivalent weight (EEW) of the epoxy resin and the empirical amine hydrogen equivalent weight (AHEW emp ) of the amine curing agent, preferably in a ratio of 1:0.8 to 1:1.2.

[0064] The curable composition according to the invention may further comprise one or more additional additives, such as inert diluents, curing accelerators, reinforcing fibers (especially glass fibers or carbon fibers), pigments, colorants, fillers, mold release agents, toughening agents, flow agents, defoaming agents, flame retardants or thickening agents. Such additives are typically added in functional amounts, i.e., for example, pigments are typically added in an amount such that the composition obtains the desired color. The composition according to the invention generally comprises a total amount of all additives of 0% to 50% b.w., preferably 0% to 20% b.w., for example 2% to 20% b.w. based on the total curable composition. In the context of the present invention, additives are understood to mean any additive in the curable composition which is neither an epoxy compound nor a reactive diluent nor an amine curing agent.

[0065] The invention further provides a method for producing a cured epoxy resin from the curable composition according to the invention. In this method, a curable composition according to the invention is provided and then cured. For this purpose, the resin component (comprising an epoxy resin and optionally a reactive diluent) and the curing component (comprising the ether-amine composition of the invention) and optionally additional components (such as inert diluents, curing accelerators, reinforcing fibers, pigments, colorants, fillers, mold release agents, toughening agents, flow agents, defoaming agents, flame retardants, thickening agents or other additives) are brought into contact with each other, mixed and then cured at a temperature suitable for application. The curing is preferably carried out under standard pressure and at a temperature of at least 0 °C, particularly preferably at least 10 °C and at a temperature of less than 250 °C, particularly preferably less than 185 °C, very particularly preferably less than 150 °C, especially at a temperature in the range of 0 °C to 185 °C, more preferably in the range of 10 °C to 150 °C, very particularly preferably in the range of 10 °C to 75 °C, especially in the range of 10 °C to 35 °C.

[0066] The invention further relates to a cured epoxy resin made from the curable composition according to the invention. The invention particularly provides a cured epoxy resin obtainable / obtained by curing the curable composition according to the invention. The invention particularly provides a cured epoxy resin obtainable / obtained by the method for producing a cured epoxy resin according to the invention.

[0067] The present invention particularly provides a method for producing a coating, in particular a floor coating, wherein a curable composition according to the present invention is provided, applied to a surface and then cured. For this purpose, the components (resin component, curing component (comprising the ether-amine composition of the present invention) and optionally further components (such as inert diluents, curing accelerators, reinforcing fibers, pigments, colorants, fillers, release agents, toughening agents, flow agents, defoaming agents, flame retardants, thickeners or other additives)) are brought into contact with each other, mixed, applied to the surface and then cured at a temperature suitable for application. The quite high reactivity of the ether-amine composition of the present invention allows curing even at temperatures below room temperature within a reasonable period of time.

[0068] Coating compositions include, for example, paints. The curable composition according to the present invention can be particularly used to obtain a scratch-resistant protective paint on any desired substrate (such as a substrate made of metal, plastic or wood material). The curable composition is also suitable as an insulating coating in electronic applications, for example as an insulating coating for wires and cables. Mention may also be made of their use for producing photoresists. They are also suitable as touch-up paints, for example also suitable for repairing pipes without dismantling them (cured-in-place pipe (CIPP) repair).

[0069] In another specific embodiment, the present invention particularly provides a method for adhering articles, wherein a curable composition according to the present invention is provided and applied to at least one surface of these articles, then these articles are attached and subsequently the curable composition is cured. For this purpose, the components (resin component, curing component (comprising the ether-amine composition of the present invention) and optionally further components (such as inert diluents, curing accelerators, reinforcing fibers, pigments, colorants, fillers, release agents, toughening agents, flow agents, defoaming agents, flame retardants, thickeners or other additives)) are brought into contact with each other, mixed, applied to at least one surface of these articles, then these articles are attached and subsequently the curable composition is cured at a temperature suitable for application. The quite high reactivity of the ether-amine composition of the present invention allows curing even at temperatures below room temperature within a reasonable period of time.

[0070] The curable composition according to the present invention is suitable for curing even in the presence of water or atmospheric humidity due to its early water resistance. Accordingly, the present invention also provides a method for producing a cured epoxy resin from the curable composition according to the present invention, wherein the curing is carried out in the presence of water or atmospheric humidity, in particular atmospheric moisture, especially at a relative atmospheric humidity of at least 50%, very particularly at a relative atmospheric humidity of at least 70%.

[0071] In the case of curing in the low temperature range (e.g., from 0 °C to 30 °C), the curable composition according to the invention combines a relatively high Shore D hardness (which is also achieved relatively quickly) with a relatively short gelling time.

[0072] Such a characteristic curve (which combines, for example, good mechanical properties, good early water resistance and rapid development of high Shore D hardness) makes the curable composition according to the invention particularly suitable for marine coatings or industrial floor coatings (“floor materials”).

[0073] The invention further provides the use of the ether-amine composition of the invention as a curing agent for epoxy resins, in particular as a curing agent for the production of epoxy resin-based coatings, in particular industrial floor coatings (“floor materials”).

[0074] Taking into account the high reactivity and having a similar characteristic curve compared to known propylene oxide-based polyetheramine hardeners such as D230 or D400, the ether-amine composition of the invention is of course a suitable curing agent for all epoxy resin applications that are known to the person skilled in the art or for which these known propylene oxide-based polyetheramine hardeners are being considered for use.

[0075] Thus, in addition to their use in coatings, the curable compositions according to the invention are also suitable as impregnating compositions, as adhesives, for the production of molded articles and composites or as casting compositions for embedding, bonding or consolidating molded articles.

[0076] The amine hydrogen equivalent weight (AHEW) can be determined theoretically or empirically, as described by B. Burton et al. (Huntsman, “Epoxy Formulations using Jeffamine Polyetheramines”, April 27, 2005, pages 8 - 11). The theoretically calculated AHEW is defined as the quotient of the amine molecular weight and the number of available hydrogens (i.e., 2 for any primary amine group of the amine plus 1 for any secondary amine group). For example, for IPDA having a molecular weight of 170.3 g / mol and 2 primary amine groups (resulting in 4 available amine hydrogens), the calculated AHEW is 170.3 / 4 = 42.6 g / eq. The determination of the empirical AHEW is based on the assumption that equivalent amounts of epoxy resin and amine hardener produce a cured epoxy resin characterized by the maximum heat distortion temperature (HDT) or the maximum glass transition temperature (T g )). Thus, to obtain the empirical AHEW, the ratio of amine hardener relative to a fixed amount of epoxy resin is varied, the blend is cured as completely as possible, and the HDT or T gAnd plot it against the reactant concentration. The empirical AHEW (AHEW emp ) is defined by the following formula:

[0077] AHEW emp =(AH max *EEW epox ) / ER

[0078] Where AH max = the amount of amine hardener (in grams) at the maximum HDT or T g

[0079] EEW epox = the EEW value of the epoxy resin used for testing

[0080] ER = the amount of epoxy resin used for testing (in grams)

[0081] In combination with the present invention, the determination of AHEW emp is based on the maximum T g (measured by DSC according to standard ASTM D 3418 (2015)). The empirical AHEW is particularly important for cases such as mixtures of polymeric amines, where a calculated AHEW is not available.

[0082] The curable composition and the hardener composition of the present invention are characterized by a relatively low initial viscosity. The initial viscosity of the curable composition can be determined as the mixing viscosity immediately after mixing the components of the curable composition according to standard DIN EN ISO 3219 (1994). The mixing viscosity is measured by a cone-plate rheometer with controlled shear stress (e.g., MCR 301, Anton Paar; where the plate and cone diameters are 50 mm, the cone angle is 1°, and the gap distance is 0.1 mm). Temperature is a key factor in such measurements because it affects the viscosity and curing rate of the curable composition. Therefore, it is necessary to measure the viscosity at a specific temperature (e.g., room temperature (23 °C)) to allow comparison.

[0083] The cured epoxy resins of the present invention are characterized by glass transition temperatures that are in a similar range compared to those cured with the corresponding commonly known propylene oxide-based polyetheramines. The glass transition temperature (T g ) can be determined by differential scanning calorimetry (DSC), for example, according to standard ASTM D 3418 (2015). A very small amount of the sample (about 10 mg) is heated (e.g., at 20 °C / min) in an aluminum crucible, and the heat flux to a reference crucible is measured. This cycle is repeated at least twice. The glass transition temperature can be determined from the heat flux curve by the inflection point, or by the half-width method, or by the midpoint temperature method. ​

[0084] The pot life can be determined according to the standard DIN 16945 (1989) (“Isothermal viscosity change”). It gives an indication of the time span from the mixed components, in which the reaction resin mass is manageable. For this purpose, the increase in viscosity is determined at a specified temperature (e.g., room temperature (23 °C)) by a rheometer (e.g., a shear stress-controlled plate-plate rheometer (e.g., MCR301, Anton Paar GmbH), where the plate diameter is e.g. 15 mm and the gap distance is e.g. 0.25 mm) until a specified viscosity limit (e.g., 6,000 mPa*s) is reached. Then the pot life is the time until this viscosity limit is reached.

[0085] According to DIN 16945 (1989), the gelling time provides information about the time period between the addition of a curing agent to the reaction mixture and the transition of the reactive resin composition from the liquid state to the gel state. Temperature plays an important role here, and therefore the gelling time is always determined for a predetermined temperature. By using dynamic-mechanical methods, especially oscillatory rheometry (e.g., a shear stress-controlled plate-plate rheometer (e.g., MCR 301, Anton Paar GmbH), where the plate diameter is e.g. 15 mm and the gap distance is e.g. 0.25 mm), small amounts of specimens can be investigated. According to the standard ASTM D 4473EN (2008), the intersection of the storage modulus G’ and the loss modulus G” (where the damping tanδ has a value of 1) is the gelling point, and the time taken from the addition of the curing agent to the reaction mixture until the gelling point is reached is the gelling time. The gelling time determined in this way can be considered a relative measure of the curing rate of the structurally relevant curing agent.

[0086] To determine the B time (which is also used as a measure of the curing speed), a sample (e.g., 0.5 g) of the freshly prepared curable composition is applied to a hot plate (e.g., at 145 °C) (e.g., without indentation) according to the standard DIN EN ISO 8987 (2005), and the time until a line (gelling point) is formed or until sudden solidification (curing) occurs is determined.

[0087] Shore hardness is a numerical measure for polymers such as cured epoxy resins, which is directly related to the penetration depth of an indenter into the test specimen and is thus a measure of the hardness of the test specimen. It is determined by way of example according to the standard DIN ISO 7619-1 (2010). A distinction is made between the Shore A, C, and D methods. The indenter used is a spring-loaded pin made of hardened steel. In the test, the indenter is forced into the test specimen by the force from the spring, and the penetration depth is a measure of the Shore hardness. For the determination of Shore hardness A and C, a frustum with a tip diameter of 0.79 mm and an insertion angle of 35° is used as the indenter, whereas for the Shore hardness D test, a frustum with a spherical tip of radius 0.1 mm and an insertion angle of 30° is used as the indenter. The Shore hardness value is determined by introducing a scale that extends from 0 Shore (penetration depth 2.5 mm) to 100 Shore (penetration depth 0 mm). Here, the scale value 0 corresponds to the maximum possible indentation, where the material offers no resistance to the penetration of the indenter. In contrast, the scale value 100 corresponds to a very high penetration resistance of the material and practically no indentation is produced. Temperature plays a decisive role in the determination of Shore hardness, and thus the measurement must be carried out according to the standard within the restricted temperature range of 23 °C ± 2 °C. In the case of floor coatings, it is generally assumed that when the Shore D hardness is 45 or above, it is possible to walk on the floor.

[0088] Early water resistance is the property of a coating to be able to come into contact with water or atmospheric humidity only a short time after application without damaging the coating. In the case of coatings based on epoxy resins and amine hardeners, such damage particularly refers to urethane formation, which is evident by the formation of white streaks or crusts (commonly referred to as "blushing" or "blooming") on the surface of the fresh coating.

[0089] In the context of the present invention, the term room temperature shall be understood to mean a temperature of 23 °C. Description of the drawings:

[0090] Figure 1 Shows the results of urethane formation (white cloudy streaks or crusts on the surface) of the hardener D230 (left figure) and i-PEA-230 (right figure) according to Example 6 after incubation for 7 days at a temperature of 13 °C and a relative atmospheric humidity of 80%. In both cases, only mild urethane formation was observed. The i-PEA-230 sample showed a slightly lower sensitivity to urethane formation compared to the D230 sample.

[0091] Examples

[0092] Example 1:

[0093] Synthesis of inverse polyetheramine ("i-PEA-400") with an average molecular weight of approximately 400 g / mol

[0094] In the first step, initially 74.85 g of dipropylene glycol (Sigma) and 0.13 g of tris(pentafluorophenyl)borane (TCI Chemicals) were charged into a 300 mL stirred vessel at a temperature of 25 °C. The vessel was made inert with nitrogen three times and heated to a temperature of 100 °C under continuous stirring. The reaction mixture was allowed to dry under vacuum for a period of 1 h. Subsequently, 165 g of propylene oxide was added slowly over a period of 1 h. After an additional reaction period of 2 h, vacuum was applied for an additional 20 min, and thereafter the temperature was reduced to 50 °C. The resulting inverse polypropylene glycol (226 g) was a colorless oil having a viscosity of 107 mPa·s and a hydroxyl value HV of 265 mg KOH / g PPG , and this hydroxyl value corresponded to an average molecular weight of 423 g / mol The viscosity was determined at a temperature of 25 °C according to DIN EN ISO 3219 (1994) using a plate-cone rheometer (Viscotester 550, Haake, with cone PK 1, 1° and plate diameter of 28 mm) at a shear rate of 40 s -1 . The hydroxyl value HV PPG was determined according to DIN 53240-1 (2013). This step has been repeated several times, and the resulting inverse polypropylene glycol has been collected for use as starting material in subsequent steps.

[0095] In the second step, 365 g of inverse polypropylene glycol, 500 g of THF, and 200 g of Al2O3-supported oxide Ni / Co / Cu-catalyst (3x3 mm chips in catalyst cages) were charged into a 3.5 L autoclave. The vessel was sealed, and 800 g of liquid ammonia was added. The autoclave was pressurized with hydrogen to a pressure of 40 bar absolute and heated to a temperature of 210 °C. At this temperature, the pressure was adjusted to 250 bar absolute with hydrogen, and the reaction mixture was stirred for 10 h. The vessel was cooled to room temperature and depressurized. Water and THF were removed from the crude product using a rotary evaporator to obtain an inverse polyetheramine (“i-PEA-400”) having a hydroxyl value HV of 261 mg KOH / g EA , a total amine value AV of 256 mg KOH / g 总计 , an amine value AV of secondary amine of 9.4 mg KOH / g sec and an amine value of tertiary amine of 0.2 mg KOH / g

[0096] AV tert , which corresponded to an amination degree D of 98.0% A and an average molecular weight of 414 g / mol The hydroxyl value was determined according to DIN 53240-1 (2013), and the amine value was determined according to the standard ASTM D 2074 (2017).

[0097] Example 2:

[0098] Synthesis of inverse-phase polyetheramine (“i-PEA-230”) with an average molecular weight of approximately 230 g / mol

[0099] In the first step, 1679 g of dipropylene glycol and 1.25 g of tris(pentafluorophenyl)borane were charged into a 6.3 L stirred vessel at a temperature of 25 °C. The vessel was purged with nitrogen three times and heated to a temperature of 100 °C with continuous stirring. After reaching the reaction temperature, 824 g of propylene oxide was added over a period of 1.5 h. After an additional 2 h reaction period, a vacuum was applied for 1 h, and thereafter the temperature was lowered to 50 °C. The resulting inverse-phase polypropylene glycol (2452 g) was a colorless oil with a viscosity of 70 mPa*s and a hydroxyl value HV of 559 mg KOH / g PPG , which corresponds to an average molecular weight of 200 g / mol

[0100] In an intermediate step, unreacted dipropylene glycol was removed from the crude inverse-phase polypropylene glycol of the first step by distillation. The crude inverse-phase polypropylene glycol containing unreacted dipropylene glycol from the first step was charged into a flask equipped with a distillation column, and the pressure was adjusted to 25 mbar. The flask was heated to a temperature of 180 °C, and dipropylene glycol was distilled off until the residual content of dipropylene glycol in the reservoir was less than 0.3% b.w. The flask was cooled to room temperature and depressurized to obtain purified inverse-phase polypropylene glycol substantially free of dipropylene glycol. The purified inverse-phase

[0101] polypropylene glycol had a hydroxyl value HV of 463 mg KOH / g PPG , which corresponds to an average molecular weight of 242 g / mol

[0102] In the final step, the purified inverse polypropylene glycol of the intermediate step is converted to the corresponding inverse polyetheramine by successive reductive amination. A tubular reactor is filled with 26 mL of an Al2O3-supported oxide Ni / Co / Cu-catalyst (3 x 3 mm pellets). For catalyst activation, the catalyst is heated to 150 °C under a nitrogen stream at atmospheric pressure. After 3 h, the nitrogen is replaced with hydrogen (100 NL / h) and the temperature is raised to 280 °C. After 24 h, the temperature is lowered to 100 °C and the hydrogen is reduced to 10 NL / h. Ammonia is fed into the reactor at 12 g / h and the temperature is raised to 200 °C. After reaching the reaction temperature, the purified inverse polypropylene glycol of the intermediate step is fed at 5.5 g / h. The product stream is depressurized to atmospheric pressure and collected. Water is removed from the crude product using a rotary evaporator to yield an inverse polyetheramine (“i-PEA-230”) having a hydroxyl value HV of 454 mg KOH / g EA and a total amine value AV of 425 mg KOH / g 总 as measured, 39.8 mg KOH / g amine value AV of secondary amines sec and 0.7 mg KOH / g amine value AV of tertiary amines tert , corresponding to an amination degree D of 93.5% A and an average molecular weight of 252 g / mol The hydroxyl value and amine value were determined as described in Example 1.

[0103] 59 ± 1 mol-% of all aminated terminal propylene oxide units in this inverse polyetheramine exhibit a reverse orientation (-CH(CH3)-CH2-NH2), as determined by 1 quantitative analysis of the 1H-NMR spectrum.

[0104] Example 3:

[0105] Preparation of a curable composition of an epoxy resin and an inverse polyetheramine

[0106] The inverse polyetheramines of Example 1 (i-PEA-400) and Example 2 (i-PEA-230) as well as the conventional polyetheramines D-400 and D-230 (BASF) are used for curing an epoxy resin (bisphenol A diglycidyl ether, Epilox A19-03, Leuna, EEW: 185 g / mol) for comparison.

[0107] AHEW of the polyetheramine emp is determined based on the ratio of the polyetheramine to the epoxy resin, which gives the maximum glass transition temperature (T g), as measured by DSC according to the standard ASTM D 3418 (2015). To harden the epoxy resin with polyetheramine, a curable composition was formulated using a 1:1 stoichiometric ratio based on the EEW and AHEW emp . The AHEW emp values and the corresponding amounts of epoxy resin and polyetheramine are summarized in Table 1. The curable composition was stirred in a propeller mixer at 2000 rpm for 1 min. Differential scanning calorimetry (DSC) and rheological experiments were carried out immediately after the preparation of the curable composition, and samples were prepared to determine the properties of the cured resin.

[0108] According to ASTM D 3418 (2015), using a heating rate of 20 °C / min starting from room temperature, a DSC (Q2000, TA Instruments) was used to determine the reaction and heat profiles (onset temperature, reaction enthalpy, and glass transition temperature (T g )) of the second run). T g was determined from the heat flux curve through the inflection point. The DSC results are also summarized in Table 1.

[0109] The rheological profiles (mixing viscosity and pot life at 23 °C, 45 °C, and 75 °C, and gel time at 23 °C, 70 °C, 90 °C, and 110 °C, and (for the i-PEA-230 and D-230 samples) B time at 145 °C) were determined using a conventional rheometer (MCR 301, Anton Paar). To measure the pot life and gel time according to DIN 16945 (1989), a shear stress-controlled plate-plate setup with a plate diameter of 15 mm and a gap distance of 0.25 mm was used in the rotational mode (pot life) or under oscillatory force (gel time). The pot life is the time required to reach a viscosity of 6,000 mPa*s at a given temperature. The gel point is defined as the intersection of the storage modulus and the loss modulus, and the gel time is defined as the time taken from the addition of the hardener to the reaction mixture to reach the gel point. To measure the mixing viscosity according to the standard DIN EN ISO 3219 (1994), a shear stress-controlled cone-plate setup of the rheometer (plate and cone diameters of 50 mm, cone angle of 1°, and gap distance of 0.1 mm) was applied. According to DIN ISO 16916 (2017) and DIN EN ISO 8987 (2005), the B time is defined as the time required for the sample (0.5 g of freshly prepared curable composition) to form a line (gel point) or until sudden solidification (curing) on a hot plate (145 °C) without indentation. The results of these tests are also summarized in Table 1.

[0110] Table 1: Thermal and rheological profiles of polyetheramine curing tests

[0111]

[0112]

[0113] Example 4:

[0114] Mechanical properties of epoxy resins cured with inverse polyetheramines

[0115] An epoxy resin (bisphenol A diglycidyl ether, Epilox A19-03, Leuna, EEW: 185 g / mol) and the inverse polyetheramine of Example 1 (i-PEA-400) or Example 2 (i-PEA-230) or, for comparison, a conventional polyetheramine D-400 or D-230 (BASF) were prepared as curable compositions as described in Example 3 and were subsequently cured at elevated temperature (2 h at 60 °C, 2 h at 80 °C, 2 h at 100 °C; specimens with a thickness of 4 mm). Mechanical parameters (tensile modulus (E-t), tensile strength (σ-M), tensile elongation flexural modulus (E-f), flexural strength (σ-fM), flexural elongation ) were determined according to ISO 527-2 (1993) and ISO 178 (2006). The Charpy test for impact resistance was carried out according to ISO 179-2 / 1eU (1997). The results of these tests are summarized in Table 2.

[0116] Table 2: Mechanical properties of epoxy resins cured with polyetheramines

[0117]

[0118] (n.d.: not determined)

[0119] Example 5:

[0120] Shore D hardness of epoxy resins cured with inverse polyetheramines

[0121] A curable composition comprising an epoxy resin (bisphenol A diglycidyl ether, Epilox A19-03, Leuna, EEW: 185 g / mol) and the inverse polyetheramine of Example 2 (i-PEA-230) or, for comparison, a conventional polyetheramine D-230 (BASF) was prepared by mixing the resin, polyetheramine, and benzyl alcohol (BnOH) in the amounts indicated in Table 3. The amount of BnOH was adjusted in such a way that the same T of 55 °C was achieved for both test compositions g .

[0122] The Shore D measurement is carried out by pouring 35 g of the curable composition into a polypropylene dish with an inner diameter of 10 cm. The composition is cured at a temperature of 0 °C (at 65% relative humidity) over a period of 8 days. During this time (after 1, 2, 3, 4, and 7 days), the Shore D hardness of the test specimens (with a thickness of 35 to 36 mm) is determined according to DIN ISO 7619-1 (2010) using a durometer (TI Shore testing bench, Sauter Messtechnik). The development of Shore D depends on two factors: the rate of network density accumulation and the polymer backbone stiffness. Here, diamines with similar backbone stiffness and functionality are compared, so the differences in Shore D development mainly depend on the reaction rate. The Shore D results are summarized in Table 3.

[0123] Table 3: Shore D hardness of epoxy resins cured with polyetheramines at 0 °C

[0124]

[0125] n.d.: not determined

[0126] Example 6:

[0127] Carbamation of epoxy resins cured with inverse polyetheramines

[0128] The curable compositions of epoxy resin (bisphenol A diglycidyl ether, Epilox A19-03, Leuna, EEW: 185 g / mol) and the inverse polyetheramine (i-PEA-230) of Example 2 or, for comparison, the conventional polyetheramine D-230 (BASF) were prepared as described in Example 3. After pouring the curable composition into a plastic Petri dish and then curing at low temperature and high relative humidity (7 days at 13 °C, 80% relative humidity; specimens with a thickness of 4 mm), the formation of carbamate on the surface of the specimens was determined by visual inspection. Both samples showed a similarly low tendency to form carbamate (visible as streaks or crusts), however, the i-PEA-230 sample showed a slightly lower sensitivity to carbamate formation compared to the D230 sample ( Figure 1 ).

Claims

1. A hardener composition comprising an ether-amine composition consisting of one or more ether-amines having the formula I wherein A = -CH(CH3)-CH2- or -CH2-CH(CH3)-, and X (independently of one another) = -CH(CH3)-CH2-NH2 or -CH2-CH(CH3)-NH2, and n≥0， Characterized in that, at least 30 mol-% of all X in the ether-amine composition is -CH(CH3)-CH2-NH2.

2. The hardener composition according to claim 1, characterized in that, At least 40 mol-% of all X in the ether-amine composition is -CH(CH3)-CH2-NH2.

3. The hardener composition according to claim 1 or 2, characterized in that, n≥1。 4. The hardener composition according to any one of claims 1 to 3, characterized in that, The total amine value of the ether-amine composition is in the range from 10 to 1000 mg KOH / g.

5. The hardener composition according to claim 4, wherein The amine value of the primary amines of the ether-amine composition of the present invention is preferably in the range of at least 80% based on the total amine value.

6. A process for producing a composition according to any one of claims 1 to 5, characterized in that in step (I), a corresponding polypropylene glycol composition is prepared by ring-opening polymerization of propylene oxide using water, propylene glycol or dipropylene glycol as initiator and an aprotic Lewis acid as catalyst, the polypropylene glycol composition having the same formula as the ether-amine of the ether-amine composition but having hydroxyl groups instead of amino groups, and in step (II), the polypropylene glycol composition of step (I) is converted into a corresponding polyetheramine composition according to any one of claims 1 to 3 by catalytic reductive amination with hydrogen and ammonia.

7. The method according to claim 6, characterized in that, The aprotic Lewis acid is selected from the group consisting of compounds: triphenylborane, diphenyl-tert-butylborane, tris(tert-butyl)borane, triphenylaluminum, diphenyl-tert-butylaluminum, tris(tert-butyl)aluminum, tris(pentafluorophenyl)borane, bis(pentafluorophenyl)-tert-butylborane, tris(pentafluorophenyl)aluminum, bis(pentafluorophenyl)-tert-butylaluminum, bis(pentafluorophenyl)fluoroborane, di(tert-butyl)fluoroborane, (pentafluorophenyl)difluoroborane, (tert-butyl)difluoroborane, bis(pentafluoro-phenyl)fluoroaluminum, di(tert-butyl)fluoroaluminum, (pentafluorophenyl)difluoroaluminum and (tert-butyl)difluoroaluminum.

8. The method according to claim 6 or 7, characterized in that, Step (II) is carried out at a temperature in the range from 150 °C to 250 °C.

9. The method according to any one of claims 6 to 8, characterized in that, In step (II), the molar ratio of ammonia to the hydroxyl groups of the polypropylene glycol composition is in the range from 5:1 to 100:

1.

10. The method according to any one of claims 6 to 9, characterized in that, Step (II) is carried out in the presence of a catalyst comprising Co, Ni, Pt, Ru, Rh, Pd or a mixture thereof as active substance.

11. The method according to any one of claims 6 to 10, characterized in that, Step (I) is followed by a purification step (I-a), in which at least part of the dipropylene glycol formed during step (I) or used as initiator is removed from the polypropylene glycol composition of step (I) before the remaining polypropylene glycol composition is used in step (II).

12. A curable composition comprising a resin component containing at least one epoxy resin and a curing component, characterized in that, The curing component is a composition according to any one of claims 1 to 5.

13. The curable composition according to claim 12, wherein The curing component comprises one or more additional amine curing agents which are not ether-amine compounds having the formula I.

14. The curable composition according to claim 12 or 13, characterized in that, The at least one epoxy resin is selected from the group consisting of: diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, diglycidyl ether of hydrogenated bisphenol A, and diglycidyl ether of hydrogenated bisphenol F.

15. The curable composition according to any one of claims 12 to 14, characterized in that, The resin component comprises one or more reactive diluents.

16. The curable composition according to any one of claims 12 to 15, characterized in that, The composition further comprises one or more additional additives.

17. A method for producing a cured epoxy resin, characterized in that Provided is a curable composition according to any one of claims 12 to 16 and subsequently curing the same.

18. A cured epoxy resin, characterized in that The resin is obtainable by providing a curable composition according to any one of claims 12 to 16 and subsequently curing the same.

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