Curable compositions containing functional polyesters and aldimines

Abstract

The invention relates to a curable composition comprising: at least one polyester polymer A with ketoester groups of formula (I), having an average functionality of at least 2 and an average equivalent weight of at least 400 g / eq; at least one compound B with ketoester groups of formula (I) and an equivalent weight of 114 to 250 g / eq, where R is a monovalent hydrocarbon radical with 1 to 10 carbon atoms; and at least one aldimine L with aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq, where Z is an aromatic or heteroaromatic five- or six-membered ring that is optionally substituted and / or fused and comprises a total of 4 to 25 carbon atoms, the weight ratio between compounds B and polyester polymers A being between 25 / 75 and 85 / 15, and the ratio between the number of ketoester groups of formula (I) and the number of aldimine groups of formula (II) being between 2 and 3. The composition is free from toxic ingredients, not sensitive to moisture, and cures under ambient conditions without emissions and unpleasant odours to form a tough-elastic polymer with high hardness, high tear resistance, and good extensibility. The composition is particularly suitable as a tough-elastic adhesive, sealant, or coating.

Description

[0001] Curable compositions containing functional polyesters and aldimines

[0002] Technical area

[0003] The invention relates to room temperature curable compositions and their use as tough elastic adhesives, sealants or coatings.

[0004] State of the art

[0005] Curable polymer compositions that achieve viscoelastic properties and can be used, for example, as adhesives, sealants, or coatings are well known. Viscoelastic products are defined as having a Shore hardness of approximately D50 or higher, an elongation at break of approximately 10% or more, and high tear resistance.

[0006] Epoxy resin compositions enable products with high hardness and strong adhesive strength. However, they generally have little ductility and are only rarely formulated to be viscoelastic. Furthermore, they tend to blush when applied over large areas, especially at low temperatures and high humidity, resulting in spotty, uneven, or sticky surfaces. Furthermore, the epoxy resins and amines they contain are often harmful to health.

[0007] Polyurethane compositions can be formulated from viscoelastic to highly elastic. However, they are sensitive to moisture during storage, application, and curing. Products with high final hardness, in particular, are prone to blistering and contain large amounts of toxic monomeric isocyanates.

[0008] Also known are compositions that crosslink via hydrolysis and condensation of silane groups. These are typically rather brittle with low tear resistance and usually contain high amounts of toxic monomeric silanes. They are also sensitive to moisture during storage, and volatile alcohols are released during curing, resulting in undesirable emissions.

[0009] US 5,288,804 describes solvent-based coatings based on acetoacetate-functional acrylate polymers, which are cured with aromatic polyaldimines. US 6,297,320 describes solvent-based corrosion protection coatings based on acetoacetate-functional acrylate polymers and low-molecular-weight acetoacetates as reactive diluents, which are cured with aliphatic ketimines. EP 1,358,286 describes solvent-based coatings based on acetoacetate-functional epoxy resins, which are cured with a ketimine-functional acrylate, with polyacetoacetates being used as reactive diluents. These coatings cause high emissions, are barely extensible, and lack viscoelastic properties.

[0010] Description of the invention

[0011] The object of the present invention is to provide a room-temperature-curable polymer composition which enables pronounced toughness and overcomes the disadvantages of the prior art with regard to toxic ingredients, moisture sensitivity, and emissions. Surprisingly, this object is achieved with a curable composition as described in claim 1. The composition comprises at least one polyester polymer A having ketoester groups of formula (I), at least one compound B having ketoester groups of formula (I), and at least one aldimine L having aldimine groups of formula (II). The weight ratio between compounds B and polyester polymers A is 25 / 75 to 85 / 15, and the ratio between the number of ketoester groups of formula (I) and the number of aldimine groups of formula (II) is 2 to 3.

[0012] The curable composition according to the invention is based on readily available starting materials and is easy to handle, as it is free of toxic ingredients and not sensitive to moisture, neither during storage nor during application and curing. It cures quickly and smoothly at room temperature without emissions or odors to form a non-sticky polymer with excellent mechanical properties. In particular, a high-quality crosslinked polymer with pronounced tough-elastic properties is formed, combining high hardness with high tear resistance and good extensibility. The combination of these properties is exceptional and cannot be derived from the systems described in the prior art.The ingredients of the inventive composition are liquid, especially at room temperature, and relatively low-viscosity, making the composition easy to process even without solvent at room temperature. Surprisingly, the composition cures completely odorlessly, even when it contains aldimines derived from volatile aldehydes such as benzaldehyde. This indicates that the aldehyde underlying the aldimine is not released but incorporated into the polymer and thus remains permanently in the cured composition.

[0013] The composition according to the invention is particularly suitable for use as an adhesive, sealant or coating, in particular for applications where high hardness and toughness are required, as well as for applications where additional aspects such as low toxicity of the ingredients, insensitivity to moisture, rapid curing under ambient conditions or low emissions are important.

[0014] 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.

[0015] Ways to implement the invention

[0016] The invention relates to a curable composition comprising

[0017] - at least one polyester polymer A containing ketoester groups of formula (I) which has an average functionality of at least 2 and an average equivalent weight of at least 400 g / eq with respect to these reactive groups,

[0018] - at least one compound B containing ketoester groups of formula (I) which has an equivalent weight of 114 to 250 g / eq with respect to these reactive groups,

[0019] OO

[0020] — O AA R (l) where R represents a monovalent hydrocarbon radical having 1 to 10 C atoms, and

[0021] - at least one aldimine L having aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq,

[0022] — N^'Z ÖD where Z is an aromatic or heteroaromatic five- or six-membered ring which is optionally substituted and / or fused and comprises a total of 4 to 25 C atoms, the weight ratio between compounds B and polyester polymers A being 25 / 75 to 85 / 15, and the ratio between the number of ketoester groups of the formula (I) and the number of aldimine groups of the formula (II) in the entire composition being 2 to 3.

[0023] A dashed line in the formulas in this document represents the bond between a substituent and the corresponding molecular residue.

[0024] A "polyester polymer" is a polymer with ester groups in the polymer main chain. It is typically produced by polycondensation reactions of polyols with polycarboxylic acids or esters, or obtained from natural glycerides. Polymers of unsaturated compounds containing ester groups, such as (meth)acrylates or vinyl esters, whose ester groups are not part of the polymer main chain but are located in the side chains, are not considered polyester polymers within the meaning of the invention.

[0025] Substance names beginning with “poly”, such as polyaldimine or polyol, refer to substances that formally contain two or more of the functional groups mentioned in their name per molecule.

[0026] The term “molecular weight” refers to the molar mass (in grams per mole) of a molecule. The term “average molecular weight” refers to the number average molecular weight (M n) of a polydisperse mixture of oligomeric or polymeric molecules. It is determined by gel permeation chromatography (GPC) using polystyrene as a standard.

[0027] A composition is considered "storage-stable" if it can be stored at room temperature in a suitable container for an extended period, typically for at least three months up to six months or more, without its application or use properties changing significantly during storage. "Room temperature" is defined as 23°C.

[0028] All industry standards and norms mentioned in this document refer to the versions valid at the time of filing the initial application. Percentages by weight (wt%) refer to the mass fraction of a component of a composition or molecule relative to the entire composition or molecule, unless otherwise specified. The terms "mass" and "weight" are used synonymously in this document.

[0029] In the curable composition, the weight ratio between compounds B and polyester polymers A ranges from 25 / 75 to 85 / 15, preferably 30 / 70 to 75 / 25. The combination of a relatively large polyester polymer A and a relatively small compound B, in the claimed weight ratio, enables pronounced toughness with exceptionally high tear resistance values ​​combined with high extensibility and high hardness. With a lower content of compounds B, hardness and tear resistance are significantly lower, and with a higher content of compounds B, high hardness is achieved, but extensibility and / or tear resistance are significantly lower.

[0030] In the case where the curable composition contains as aldimine L an aldimine derived from a polyetherdiamine or polyethertriamine, the weight ratio between compounds B and polyester polymers A is preferably in the range of 40 / 60 to 85 / 15.

[0031] In the curable composition, the ratio between the number of ketoester groups of formula (I) and the number of aldimine groups of formula (II) is 2 to 3. Surprisingly, particularly good mechanical properties are obtained in this range. Preferably, the ratio between the number of ketoester groups of formula (I) and the number of aldimine groups of formula (II) is 2.3 to 2.7, especially about 2.5.

[0032] The polyester polymer A and the compound B contain ketoester groups of the formula (I), where R represents a monovalent hydrocarbon radical having 1 to 10 C atoms.

[0033] Preferably, R is methyl, ethyl, propyl, isopropyl, butyl or phenyl, in particular methyl or phenyl.

[0034] Particularly preferably, R represents methyl, and the ketoester groups of formula (I) thus represent acetoacetate groups. Polyester polymers A and compounds B containing acetoacetate groups are particularly easily accessible and enable compositions with particularly rapid curing.

[0035] Polyester polymer A has an average functionality of at least 2 and an average equivalent weight of at least 400 g / eq. This enables high extensibility and toughness of the cured composition.

[0036] The polyester polymer A preferably has an average functionality of 2 to 3.

[0037] The polyester polymer A preferably has an average equivalent weight of 400 to 2,500 g / eq, in particular 450 to 1,500 g / eq.

[0038] Preferably, the polyester polymer A has an average molecular weight M n from 800 to 5,000 g / mol, in particular 1,000 to 3,000 g / mol.

[0039] Particularly preferably, the polyester polymer A has an average functionality of 2 to 3 and an average equivalent weight of 400 to 2,500 g / eq, in particular 450 to 1,500 g / eq.

[0040] Preferably, the polyester polymer A is obtained from the transesterification of at least one polyester polyol with at least one 1,3-ketoester of the formula (IV), where R 1 is C1-6 alkyl and R has the meanings already given. Preferably R 1 for methyl, ethyl or tert-butyl, particularly preferably for ethyl or tert-butyl, in particular for ethyl.

[0041] The transesterification is preferably carried out at a temperature in the range of 50 to 180 °C with distillative removal of the released alcohol R 1OH and optionally fragmentation products thereof, optionally under vacuum and optionally in the presence of a suitable catalyst.

[0042] It is also possible to produce a polyester polymer A by reacting the polyester polyol with diketene or the adduct of diketene with acetone (= 2,2,6-trimethyl-4H-1,3-dioxin-4-one), whereby in the case of the acetone-diketene adduct, acetone is released.

[0043] In a preferred embodiment of the invention, the polyester polymer A is derived from an amorphous polyester polyol which is liquid at room temperature.

[0044] Preference is given to an amorphous, saturated polyester diol or triol which is liquid at room temperature, in particular from the reaction of dicarboxylic acids such as in particular succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid or dodecanedicarboxylic acid, with alcohols such as in particular 1,2-ethanediol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, trimethylolpropane, isosorbide or glycerol.

[0045] This results in compositions that are particularly easy to process and have particularly good water resistance after curing.

[0046] In a further preferred embodiment of the invention, the polyester polymer A is a reaction product of castor oil.

[0047] One such polyester polymer A is based, in particular, on a castor oil-derived polyester polyol, such as Setathane® D 1150 (from Allnex). It enables particularly high strengths and is particularly sustainable due to its high bio-based carbon content.

[0048] In a further preferred embodiment of the invention, the polyester polymer A is an amorphous polyester from the esterification of a dimer fatty acid or trimer fatty acid or a dimer fatty alcohol or trimer fatty alcohol.

[0049] Such a polyester polymer A enables particularly high strengths and is particularly sustainable due to its high proportion of bio-based carbon.

[0050] Polyester polymer A is preferably liquid at room temperature. In particular, it has a viscosity at 20 °C of 0.5 to 100 Pa s, preferably 0.5 to 50 Pa s, in particular 1 to 20 Pa s, measured using a cone-plate viscometer with a cone diameter of 10 mm, a cone angle of 1°, a cone tip-to-plate distance of 0.05 mm, and a shear rate of 10 s -1 Such a polymer is easy to handle at ambient temperatures even without the addition of solvents or thinners and enables easy-to-process compositions.

[0051] The curable composition further comprises at least one compound B having ketoester groups of formula (I) and an equivalent weight of 114 to 250 g / eq.

[0052] Preferably, compound B has two to four, in particular two to three, ketoester groups of formula (I).

[0053] Preferably, compound B has an equivalent weight of 114 to 200 g / eq.

[0054] The compound B is in particular an ester of a polyalcohol with at least one 1,3-ketoester of formula (IV) with release and removal of the alcohol of formula R 1 OH and optionally fragmentation products thereof, prepared as previously described for a polyester polymer A having ketoester groups of formula (I).

[0055] Suitable polyalcohols for the preparation of a compound B are, in particular, 1,2-ethanediol, diethylene glycol, triethylene glycol, 1,2-propanediol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,4-butanediol, 1,2-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, 1,2-pentanediol, neopentyl glycol, 2-methyl-1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 2-ethyl-1,3-hexanediol, 1,10-decanediol, 1,12-dodecanediol, polytetrahydrofurandiol with medium molecular weight M nfrom 150 to 300 g / mol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, isosorbide, 2,5-bis(hydroxymethyl)tetrahydrofuran, 2,5(6)-bis(hydroxymethyl)bicyclo[2.2.1]heptane, 3(4),8(9)-Bis(hydroxymethyl)tricyclo[5.2.1.0 2 ' 6 ]decane, hydrogenated bisphenol F, hydrogenated bisphenol A, glycerol, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, ethoxylated or in particular propoxylated glycerol, or ethoxylated or in particular propoxylated 1,1,1-trimethylolpropane.

[0056] Preferred are 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, isosorbide, hydrogenated bisphenol A, glycerol, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane or propoxylated 1,1,1-trimethylolpropane with medium molecular weight M n from 250 to 500 g / mol.

[0057] Glycerin, 1,1,1-trimethylolpropane or isosorbide are particularly preferred.

[0058] Preferably, compound B is selected from the list consisting of 1,4-butanediol diacetoacetate, 2-methyl-1,3-propanediol diacetoacetate, 1,5-pentanediol diacetoacetate, neopentylglycol diacetoacetate, 1,6-hexanediol diacetoacetate, 3-methyl-1,5-pentanediol diacetoacetate, 2-ethyl-1,3-hexanediol diacetoacetate, isosorbide diacetoacetate, 4,4'-isopropylidene-bis(cyclohexanol)diacetoacetate, glycerol diacetoacetate, glycerol triacetoacetate, 1,1,1-trimethylolethane diacetoacetate, 1,1,1-trimethylolethane triacetoacetate, 1,1,1-trimethylolpropane diacetoacetate, 1 , 1 , 1 -T rimethylolpropane triacetoacetate and the triacetoacetate of propoxylated 1 ,1 ,1-trimethylolpropane with a total average molecular weight M n from 500 to 750 g / mol. These compounds B are readily accessible and enable high hardness with high ductility.

[0059] 3-Methyl-1,5-pentanediol diacetoacetate is particularly preferred. This yields polymers with high strength. 2-Ethyl-1,3-hexanediol diacetoacetate is also particularly preferred. This yields polymers with particularly high water resistance.

[0060] Glycerol triacetoacetate or a mixture of glycerol diacetoacetate and glycerol triacetoacetate is also particularly preferred. Such a compound B enables high strengths with good processability.

[0061] Also particularly preferred is 1,1,1-trimethylolpropane triacetoacetate. This compound B enables particularly high tear resistance.

[0062] Isosorbide diacetoacetate is also particularly preferred. This provides particularly high strength and tear resistance, especially in combination with a polyester polymer A based on a dimer or trimer fatty acid.

[0063] The curable composition further comprises at least one aldimine L having aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq.

[0064] — N^'Z ÖD

[0065] The aldimine L preferably has one to three, in particular two to three, aldimine groups of the formula (II).

[0066] Preferably, Z in the aldimine groups of the formula (II) represents an optionally substituted phenyl radical, an optionally substituted naphthyl radical or an optionally substituted furyl radical, pyridine radical, pyrrole radical, indole radical or thiophene radical, in particular an optionally substituted phenyl radical, an optionally substituted naphthyl radical or an optionally substituted furyl radical.

[0067] Insbesondere ist Z ausgewählt aus der Liste bestehend aus Phenyl, 2-Methyl- phenyl, 3-Methylphenyl, 4-Methylphenyl, 4-Ethylphenyl, 4-lsopropylphenyl, 4-tert- Butylphenyl, 4-Cw-i4-Alkylphenyl, 2-Hydroxyphenyl, 3-Hydroxyphenyl, 4-Hydroxy- phenyl, 2,5-Dimethylphenyl, 2-Methoxyphenyl, 3-Methoxyphenyl, 4-Methoxyphe- nyl, 2-Ethoxyphenyl, 3-Ethoxyphenyl, 4-Ethoxyphenyl, 4-Propoxyphenyl, 4-lsopro- poxyphenyl, 4-Butoxyphenyl, 4-Pentoxyphenyl, 4-Decyloxyphenyl, 4-Dodecyloxy- phenyl, 2,3-Dimethoxyphenyl, 2,4-Dimethoxyphenyl, 2,5-Dimethoxyphenyl, 3,4- Dimethoxyphenyl, 3,5-Dimethoxyphenyl, 4-Hydroxy-3-methoxyphenyl, 2,4,6-Tri- methylphenyl, 2,4,5-Trimethoxyphenyl, 2,4,6-Trimethoxyphenyl, 3,4,5-Trimethoxy- phenyl, 4-Methoxycarbonylphenyl, 4-Ethoxycarbonylphenyl, 3-Nitrophenyl, 1- Naphthyl, 2-Naphthyl, 2-Furyl, 5-Methyl-2-furyl und 5-Hydroxymethyl-2-furyl.

[0068] Particularly preferred are phenyl, 4-methoxycarbonylphenyl, 4-ethoxycarbonylphenyl, 3-nitrophenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 4-methoxyphenyl, 3,4-dimethoxyphenyl, 2-furyl, 5-methyl-2-furyl or 5-hydroxymethyl-2-furyl, especially phenyl, 4-Methoxycarbonylphenyl, 3-nitrophenyl, 2-furyl or 5-methyl-2-furyl.

[0069] Most preferably, Z is phenyl. These aldimines are derived from benzaldehyde. They are particularly readily available and allow for particularly rapid curing.

[0070] Aldimines derived from benzaldehyde or other volatile aldehydes typically cause a strong, unpleasant odor in curable compositions, which is clearly noticeable during and after application and severely limits their use. Surprisingly, however, the curable composition according to the invention does not produce an aldehyde odor, which is particularly advantageous since the composition can be used without restriction even in odor-sensitive applications, for example, in building interiors or in automobiles.

[0071] Preferred as aldimine L is an aldimine of formula (III), where n is 2 or 3 and G is an n-valent organic radical having 2 to 25 C atoms and Z has the meanings already mentioned.

[0072] Preferably, G represents a divalent hydrocarbon radical having 5 to 15 carbon atoms or a divalent or trivalent polyoxyalkylene radical having an average molecular weight Mn of 160 to 500 g / mol. The aldimine of formula (III) is derived from a primary amine and an aromatic or heteroaromatic aldehyde, from which it is obtainable by a condensation reaction.

[0073] Preferred primary amines are commercially available aliphatic or cycloaliphatic primary amines, in particular selected from the list consisting of 1,2-ethanediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 2,2-dimethyl-1,3-propanediamine, 1,3-pentanediamine (DAMP), 1,6-hexanediamine, 1,5-diamino-2-methylpentane (MPMD), 1,7-heptanediamine, 1,8-octanediamine, 2,5-dimethyl-1,6-hexanediamine, 1,9-nonanediamine, 2,2(4),4-trimethyl-1,6-hexanediamine (TMD), 1 ,10-decanediamine, 1,11-undecanediamine, 2-butyl-2-ethyl-1,5-pentanediamine (C11-neodiamine), 1,12-dodecanediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1 ,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-bis(aminomethyl)benzene (MXDA), isophoronediamine (IPDA), 2(4)-methyl-1,3-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,5(6)-Bis(aminomethyl)bicyclo[2.2.1]heptane (NBDA), 3(4),8(9)-Bis(ami- nomethyl)tricyclo[5.2.1 .0 2 ' 6]decane (TCD-diamine), 4,9-dioxadodecane-1 , 12-diamine, 4,7,10-trioxatridecane-1 ,13-diamine, polyoxypropylenediamines with an average molecular weight M n from 200 to 500 g / mol and polyoxypropylenetriamines with an average molecular weight Mn of 300 to 500 g / mol.

[0074] Preferred polyoxypropylene di- or triamines are Jeffamine® D-230, Jeffamine® D-400 or Jeffamine® T-403 (all from Huntsman), as well as equivalent grades from BASF or Nitroil.

[0075] Als aromatischer oder heteroaromatischer Aldehyd bevorzugt sind Benzaldehyd, 2-Tolualdehyd, 3-Tolualdehyd, 4-Tolualdehyd, 4-Ethylbenzaldehyd, 4-lsopropyl- benzaldehyd, 4-tert-Butylbenzaldehyd, 4-Cio-i4-Alkylbenzaldehyd, Salicylaldehyd, alkoxylierter Salicylaldehyd wie insbesondere 2-(2-Hydroxyethoxy)benzaldehyd, 3- Hydroxybenzaldehyd, 4-Hydroxybenzaldehyd, 2,5-Dimethylbenzaldehyd, 2-Me- thoxybenzaldehyd, 3-Methoxybenzaldehyd, 4-Methoxybenzaldehyd, 2-Ethoxy- benzaldehyd, 3-Ethoxybenzaldehyd, 4-Ethoxybenzaldehyd, 4-Propoxybenzalde- hyd, 4-lsopropoxybenzaldehyd, 4-Butoxybenzaldehyd, 4-Pentoxybenzaldehyd, 4- Decyloxybenzaldehyd, 4-Dodecyloxybenzaldehyd, 2,3-Dimethoxybenzaldehyd, 2,4-Dimethoxybenzaldehyd, 2,5-Dimethoxybenzaldehyd, 3,4-Dimethoxybenzalde- hyd, 3,5-Dimethoxybenzaldehyd, 4-Hydroxy-3-methoxybenzaldehyd (Vanillin), 2,4,6-T rimethylbenzaldehyd, 2,4,5-T rimethoxybenzaldehyd, 2,4,6-T rimethoxy- benzaldehyd, 3,4,5-Trimethoxybenzaldehyd, 4-Formylbenzoesäureester,in particular 4-formylbenzoic acid methyl ester or 4-formylbenzoic acid ethyl ester, 3-nitrobenzaldehyde, 1-naphthaldehyde, 2-naphthaldehyde, furfural, 5-methylfurfural or 5-hydroxymethylfurfural.

[0076] Particularly preferred is benzaldehyde, 4-formylbenzoic acid methyl ester, 4-formylbenzoic acid ethyl ester, 3-nitrobenzaldehyde, tolualdehyde, 4-methoxybenzaldehyde, furfural, 5-methylfurfural or 5-hydroxymethylfurfural, in particular benzaldehyde, 4-formylbenzoic acid methyl ester, 3-nitrobenzaldehyde, furfural or 5-methylfurfural.

[0077] Benzaldehyde is most preferred.

[0078] Aldimines of formula (III) sometimes exhibit a distinct tendency to crystallize. Preferred aldimines of formula (III) are those that, either as such or as mixtures with one another, are permanently liquid at room temperature without the addition of solvents or diluents. Such aldimines enable compositions with low emissions.

[0079] Preferred aldimines of formula (III) are selected from the list consisting of N,N'-dibenzylidene-1,5-pentanediamine, N,N'-dibenzylidene-1,6-hexanediamine, N,N'-dibenzylidene-2-methyl-1,5-pentanediamine, N,N'-dibenzylidene-2,2(4),4-trimethyl-1,6-hexanediamine, N,N'-dibenzylidene-1,3-bis(aminomethyl)cyclohexane, N,N'-dibenzylidene-1,3-bis(aminomethyl)benzene, N,N'-dibenzylideneisophoronediamine, N,N'-dibenzylidene-4,4'-methylene-bis(cyclohexylamine), N,N'-dibenzylidenepolyoxypropylenediamines with medium molecular weight M n from 350 to 750 g / mol and N,N',N"-tribenzylidenepolyoxypropylenetriamines with medium molecular weight M n from 450 to 700 g / mol, as well as the analogous aldimines derived from 4-formylbenzoic acid methyl ester, 4-formylbenzoic acid ethyl ester, 3-nitrobenzaldehyde, tolualdehyde, 4-methoxybenzaldehyde, furfural, 5-methylfurfural and 5-hydroxymethylfurfural instead of benzaldehyde.

[0080] Particularly preferred are N,N'-dibenzylidene-1,5-pentanediamine, mixtures of N,N'-dibenzylidene-1,5-pentanediamine and N,N'-dibenzylidene-1,6-hexanediamine, in particular in a molar ratio of about 1:1, N,N'-dibenzylidene-2-methyl-1,5-pentanediamine, N,N'-dibenzylidene-2,2(4),4-trimethyl-1,6-hexanediamine, N,N'-dibenzylidenepolyoxypropylenediamines with medium molecular weight M n from 350 to 750 g / mol, as well as mixtures thereof with another aldimine of formula (III). These aldimines or aldimine mixtures have little tendency to crystallize and are typically permanently liquid at room temperature.

[0081] N,N'-Dibenzylidene-1,5-pentanediamine is particularly preferred. This results in particularly high strengths.

[0082] Furthermore, N,N'-dibenzylidene-2,2(4),4-trimethyl-1,6-hexanediamine is very particularly preferred.

[0083] Furthermore, very particular preference is given to N,N'-dibenzylidenepolyoxypropylenediamines with medium molecular weight M n from 350 to 750 g / mol, especially 400 to 500 g / mol. This results in particularly good extensibility and toughness.

[0084] Preferably, polyester polymer A, compound B, and aldimine L are each liquid at room temperature. In particular, they are easily handled in the liquid state at room temperature without the addition of solvents or thinners. Such a composition offers good processability with particularly low emissions.

[0085] The curable composition may additionally contain other components, in particular

[0086] - Fillers, in particular ground or precipitated calcium carbonates, which may be coated with fatty acids, in particular stearates, barites (heavy spars), quartz flours, quartz sands, dolomites, wollastonites, kaolins, calcined kaolins, phyllosilicates such as mica or talc, zeolites, aluminum hydroxides, magnesium hydroxides, silicas including highly dispersed silicas from pyrolysis processes, industrially produced carbon blacks, graphite, ground fillers from agricultural sources such as olive kernel flour or nutshell flour, metal powders, for example of aluminum, copper, iron, silver or steel, PVC powders or hollow spheres,

[0087] - fibres, in particular glass fibres, carbon fibres, metal fibres, ceramic fibres, hemp fibres, cellulose fibres or plastic fibres such as polyamide fibres, polyethylene fibres or polypropylene fibres,

[0088] - Nanofillers or nanofibers such as graphene or carbon nanotubes,

[0089] - dyes,

[0090] - Pigments, in particular titanium dioxide, chromium oxide, iron oxides or organic pigments,

[0091] - Plasticizers, in particular phthalates, in particular diisononyl phthalate (DINP), diisodecyl phthalate (DIDP) or di(2-propylheptyl)phthalate (DPHP), hydrogenated phthalates, in particular diisononyl 1,2-cyclohexanedicarboxylate (DINCH), terephthalates, in particular bis(2-ethylhexyl)terephthalate or diisononyl terephthalate (DINT), hydrogenated terephthalates, in particular bis(2-ethylhexyl)1,4-cyclohexanedicarboxylate or diisononyl1,4-cyclohexanedicarboxylate, isophthalates, trimellitates, adipates, in particular dioctyl adipate (DOA), azelates, sebacates, citrates, benzoates, glycol ethers, glycol esters, plasticizers with polyether structure, in particular poly(oxy-1,2-propylene) monols, diols or triols, optionally with blocked Hydroxyl groups, in particular in the form of acetyl groups, as well as organic sulfonates or phosphates, in particular diphenyl cresyl phosphate (DPK) or tris-2-ethylhexyl phosphate (TOF), polybutenes, polyisobutenes or plasticizers derived from natural fats or oils,in particular epoxidized soy or linseed oil or rapeseed oil methyl ester, with phthalates, hydrogenated phthalates, adipates or plasticizers with polyether structure being preferred,

[0092] - Catalysts for the reaction of 1,3-ketoester groups with aldimine groups,

[0093] - solvents,

[0094] - Modifiers such as hydrocarbon resins, natural or synthetic waxes or bitumen, - Rheology modifiers, in particular urea compounds, phyllosilicates such as bentonites, derivatives of castor oil, hydrogenated castor oil, polyamides, polyurethanes, pyrogenic silicas or hydrophobically modified polyoxyethylenes,

[0095] - drying agents, in particular molecular sieves, calcium oxide, mono-oxazolidines such as lncozol® 2 (from Incorez), orthoesters or alkoxysilanes,

[0096] - Adhesion promoters, in particular titanates or organoalkoxysilanes such as aminosilanes, mercaptosilanes, epoxysilanes, (meth)acrylsilanes, carbamatosilanes, alkylsilanes, S-(alkylcarbonyl)mercaptosilanes or oligomeric forms of these silanes,

[0097] - non-reactive thermoplastic polymers, such as homo- or copolymers of unsaturated monomers, in particular from the group comprising ethylene, propylene, butylene, isobutylene, isoprene, styrene, vinyl acetate and alkyl (meth)acrylates, in particular polyethylenes (PE), polypropylenes (PP), polyisobutylenes, ethylene-vinyl acetate copolymers (EVA) and atactic poly-α-olefins (APAO),

[0098] - flame-retardant substances, in particular the fillers already mentioned, aluminium hydroxide or magnesium hydroxide, organic phosphoric acid esters, ammonium polyphosphates, expanding graphite, melamine compounds, boron compounds or antimony compounds,

[0099] - Additives, in particular wetting agents, flow control agents, defoamers, deaerators, stabilizers against oxidation, heat, light or UV radiation or biocides, as well as other substances commonly used in curable compositions.

[0100] The curable composition preferably contains less than 10% by weight, more preferably less than 5% by weight, and especially less than 1% by weight, of volatile organic compounds (VOCs) with a boiling point at atmospheric pressure of less than 250°C, particularly organic solvents, based on the total composition. Such a composition causes particularly low emissions.

[0101] The curable composition is preferably not water-based, meaning it is neither a solution nor an emulsion or dispersion in water. It is preferably largely free of water or contains only a low water content. Such a composition cures rapidly regardless of ambient humidity, can be used in thick layers and / or between waterproof substrates, and exhibits hardly any shrinkage during curing. The curable composition preferably contains less than 5% by weight, preferably less than 2% by weight, in particular less than 1% by weight, of water based on the total composition.

[0102] The curable composition is preferably used in the form of a two-component system.

[0103] The composition preferably comprises a component K1 and a component K2, each of which is individually stable and stored in separate containers. Compounds containing ketoester groups of formula (I) are part of component K1, and aldimines containing aldimine groups of formula (II) are part of component K2. Such a curable composition is also referred to as a two-component composition. The two components K1 and K2 are individually stable and stored in separate containers until they are mixed together shortly before or during application, thus beginning curing.

[0104] Further ingredients of the composition may be present in component K1 and / or K2. Substances reactive with aldimine groups of formula (II) are preferably a component of component K1. Substances reactive with ketoester groups of formula (I) are preferably a component of component K2.

[0105] The consistency of component K1 and component K2 is suitable for mixing easily under ambient conditions using simple methods. Liquid or pasty components are particularly suitable for this purpose. Component K1 and component K2 of the curable composition are prepared separately. The ingredients of each component are mixed together to form a macroscopically homogeneous mass. Components K1 and K2 are each stored in separate containers. Suitable containers include, in particular, drums, containers, hobbocks, buckets, canisters, cans, bags, tubular bags, cartridges, or tubes.

[0106] To apply the curable composition, all ingredients, particularly components K1 and K2, are mixed together shortly before or during application. The mixing ratio is preferably selected such that the ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II) is within the range according to the invention. In parts by weight, the mixing ratio is typically in the range of approximately 50:1 to 1:5, in particular 10:1 to 1:2.

[0107] If the components are mixed together prior to application, care must be taken to ensure that not too much time elapses between mixing the components and application, as otherwise the onset of the reaction and the associated increase in viscosity may lead to problems such as insufficient flow or slow or incomplete adhesion to the substrate. In particular, the open time of the composition during application should not be exceeded.

[0108] The “open time” is the period of time between the mixing of the components and the end of a state of the composition suitable for processing.

[0109] Mixing is preferably carried out at ambient temperature, preferably at a temperature in the range of -5 to 50 °C, preferably 0 to 40 °C, in particular 5 to 35 °C.

[0110] When the ingredients or components are mixed, the composition begins to cure through the onset of a chemical reaction. It can be assumed that two ketoester groups of formula (I) typically react with an aldimine group of formula (II) to form a cycloaliphatic structural unit, releasing water. The observation that no aldehyde odor is detectable during or after curing when using aldimines L derived from benzaldehyde indicates that the aldehyde underlying the aldimine is not released during the curing reaction but is incorporated into the polymer and thus remains permanently in the cured composition.

[0111] Curing preferably takes place at ambient temperature, preferably at a temperature in the range of -5 to 50°C, in particular 0 to 40°C.

[0112] Another object of the invention is the cured composition obtained from the curable composition after mixing the ingredients or components and subsequent curing.

[0113] Preferably, the cured composition has good extensibility, high tear resistance, high tensile strength and high Shore hardness.

[0114] The cured composition preferably has an elongation at break of at least 5%, preferably at least 10%, particularly preferably at least 20%, in particular at least 40%, determined according to DIN EN 53504 on dumbbell-shaped test specimens (length 75 mm, web length 30 mm, web width 4 mm, thickness 2 mm) at a tensile speed of 200 mm / min.

[0115] The cured composition preferably has a tear resistance of at least 20 N / mm, in particular at least 40 N / mm, determined according to DIN ISO 34-1 method B (angular test specimen) with a sample thickness of 2 mm and a tensile speed of 500 mm / min.

[0116] The cured composition preferably has a tensile strength of at least 8 MPa, preferably at least 12 MPa, in particular at least 15 MPa, determined according to DIN EN 53504 on dumbbell-shaped test specimens (length 75 mm, web length 30 mm, web width 4 mm, thickness 2 mm) at a tensile speed of 200 mm / min. The cured composition preferably has a Shore D hardness of at least 50, preferably at least 65, determined according to DIN 53505 on cylindrical test specimens (diameter 20 mm, thickness 5 mm).

[0117] The cured composition preferably has a glass transition temperature (Tg) of at least 50 °C, preferably at least 65 °C, determined by DMTA on strip-shaped samples (length 75 mm, width 10 mm, thickness 2 mm) in shear mode with an excitation frequency of 10 Hz in the temperature range from -80 to 120 °C at a heating rate of 5 K / min, while determining the complex elastic modulus, with a maximum in the loss angle curve being read off as the Tg value. A high Tg enables good resistance at high service temperatures.

[0118] In particular, the cured composition has an elongation at break of at least 5%, preferably at least 10%, particularly preferably at least 20%, in particular at least 40%, and a tear resistance of at least 20 N / mm, in particular at least 40 N / mm.

[0119] The curable composition is suitable for a wide range of applications. It is used in particular as an adhesive, sealant, coating, casting resin, or filler.

[0120] A further object of the invention is the use of the curable composition as an adhesive, sealant or coating, wherein the ingredients or components are mixed together and the mixed composition is applied in the liquid state to at least one substrate.

[0121] Suitable substrates include:

[0122] - Glass, glass ceramics, concrete, mortar, cement screed, fiber cement, brick, tile, plaster or natural stones such as granite or marble;

[0123] - Repair or leveling compounds based on PCC (polymer-modified cement mortar) or ECO (epoxy resin-modified cement mortar); - Metals or alloys such as aluminum, iron, steel, copper, and other non-ferrous metals, including surface-treated metals or alloys such as galvanized or chrome-plated metals;

[0124] - asphalt or bitumen;

[0125] - 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;

[0126] - 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;

[0127] - 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);

[0128] - Insulating materials, in particular foams, in particular EPS, XPS, PUR, PIR, aerogel or foamed glass (foam glass), or fibres made of rock wool or glass wool,

[0129] - coated or painted substrates, in particular painted tiles, painted concrete, powder-coated metals or alloys or painted sheets;

[0130] - Coatings, paints or varnishes.

[0131] 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.

[0132] Two similar or two different substrates can be bonded and / or sealed.

[0133] An article is obtained from the use of the curable composition. The article consists of the cured composition or is bonded, sealed, or coated with it. This article may be a building or a part thereof, in particular a building or civil engineering structure, a bridge, a roof, a staircase, or a facade, or it may be an industrial or consumer good, in particular a window, a pipe, a rotor blade of a wind turbine, a household appliance, or a means of transport, such as, in particular, an automobile, a bus, a truck, a rail vehicle, a ship, an aircraft, or a helicopter, or an attachment thereof.

[0134] Examples

[0135] The following are exemplary embodiments intended to further illustrate the described invention. Of course, the invention is not limited to these described exemplary embodiments.

[0136] The “standard climate” (“NK”) is defined as a temperature of 23±1 °C and a relative humidity of 50±5%.

[0137] Unless otherwise stated, the chemicals used were from Merck.

[0138] The viscosity was measured on a thermostatted cone-plate viscometer Rheotec RC30 (cone diameter 10 mm, cone angle 1 °, cone tip-plate distance 0.05 mm, shear rate 10 s' 1 ) measured. Viscosities of less than 0.5 Pa s were measured with a cone diameter of 50 mm and a shear rate of 100 s' 1 measured.

[0139] Infrared spectra (FT-IR) were measured as undiluted films on a Thermo Scientific Nicolet iS5 FT-IR instrument equipped with a horizontal diamond crystal ATR measurement unit.

[0140] Production of polyester polymers with ketoester groups of formula (I):

[0141] Polymer A-1 :

[0142] 500 g (1 mol OH) of saturated polyesterdiol (Oxyester® T 1136, OH number 112 mg KOH / g, from Evonik) was mixed with 174 g (1.1 mol) of tert-butylacetoacetate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm -1 had disappeared and no more volatiles were separated. 582.7 g of a clear, yellowish liquid with a viscosity at 20 °C of 2.4 Pa s, an acetoacetate functionality of 2, and a theoretical acetoacetate equivalent weight of 584 g / g were obtained.

[0143] Polymer A-2: 500 g (1.1 mol OH) of amorphous dimer fatty acid-based polyesterdiol with an OH number of 123 mg KOH / g was treated with 156.2 g (1.2 mol) of ethyl acetoacetate and 0.6 g of tetra-n-butyl titanate (Tyzor® TnBT, from Dorf Ketal) and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm was observed in the FT-IR. -1had disappeared and no more volatiles were separated. 608.7 g of a clear, yellowish liquid with a viscosity at 20 °C of 14.4 Pa s, an acetoacetate functionality of 2, and a theoretical acetoacetate equivalent weight of 540 g / eq were obtained.

[0144] Preparation of compounds with ketoester groups of formula (I):

[0145] Compound B-1 :

[0146] 92.1 g (1 mol) of glycerol (= 1,2,3-trihydroxypropane) was treated with 506 g (3.2 mol) of tert-butylacetoacetate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm' was observed in the FT-IR. 1 had disappeared and no more volatiles were separated. 327.6 g of glycerol triacetoacetate were obtained as a clear, yellowish liquid with a viscosity at 20 °C of 0.12 Pa s and a theoretical acetoacetate equivalent weight of 114.7 g / eq.

[0147] Connection B-2:

[0148] 134.2 g (1 mol) of 1,1,1-trimethylolpropane was treated with 522.1 g (3.3 mol) of tert-butyl acetoacetate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm was observed in the FT-IR. -1 had disappeared and no more volatiles were separated. 367.3 g of 1,1,1-trimethylolpropane triacetoacetate were obtained as a clear, yellowish liquid with a viscosity at 20 °C of 0.27 Pa s and a theoretical acetoacetate equivalent weight of 129 g / eq.

[0149] Connection B-3:

[0150] 146.1 g (1 mol) of isosorbide was treated with 348.0 g (2.2 mol) of tert-butylacetoacetate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm -1had disappeared and no more volatiles were separated. 310.6 g of isosorbide diacetoacetate were obtained as a clear, yellowish liquid with a viscosity at 20 °C of 0.91 Pa s and a theoretical acetoacetate equivalent weight of 157 g / eq.

[0151] Connection B-4:

[0152] 104.1 g (1 mol) of neopentyl glycol (= 2,2-dimethyl-1 ,3-propanediol) was treated with 286.3 g (2.2 mol) of ethyl acetoacetate and 0.3 g of tetra-n-butyl titanate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm -1 had disappeared and no more volatile substances were separated. 267.1 g of neopentyl glycol diacetoacetate were obtained as a clear, yellowish liquid with a viscosity at 20 °C of < 0.05 Pa s and a theoretical acetoacetate equivalent weight of

[0153] 136 g / eq.

[0154] Compound B-5:

[0155] 118.2 g (1 mol) of 3-methyl-1,5-pentanediol was treated with 286.3 g (2.2 mol) of ethyl acetoacetate and 0.3 g of tetra-n-butyl titanate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm' was observed in the FT-IR. 1 had disappeared and no more volatiles were separated. 282.4 g of 3-methyl-1,5-pentanediol diacetoacetate were obtained as a clear, yellowish liquid with a viscosity at 20 °C of < 0.05 Pa s and a theoretical acetoacetate equivalent weight of 143 g / eq.

[0156] Connection B-6:

[0157] 146.2 g (1 mol) of 2-ethyl-1,3-hexanediol was treated with 286.3 g (2.2 mol) of ethyl acetoacetate and 0.3 g of tetra-n-butyl titanate and reacted at a temperature of 140 °C under vacuum until the broad OH band in the range of 3,300 to 3,600 cm was observed in the FT-IR. -1had disappeared and no more volatiles were separated. 310.8 g of 2-ethyl-1,3-hexanediol diacetoacetate were obtained as a clear, yellowish liquid with a viscosity at 20 °C of < 0.05 Pa s and a theoretical acetoacetate equivalent weight of 157 g / eq. Preparation of aldimines:

[0158] Aldimine L-1 :

[0159] 106.1 g (1 mol) of benzaldehyde was initially charged under a nitrogen atmosphere, mixed with 124.0 g (1 mol NH2) of polyoxypropylenediamine (Jeffamine® D-230, from Huntsman) with vigorous stirring, and the volatile components were subsequently removed at 80 °C and a vacuum of 10 mbar. This yielded 210.7 g of a clear, yellowish liquid with a viscosity at 20 °C of 0.34 Pa s, an amine number of 265 mg KOH / g, and an aldimine equivalent weight of 212 g / eq.

[0160] Aldimine L-2:

[0161] 212.2 g (2 mol) of benzaldehyde were initially charged under a nitrogen atmosphere, mixed with 102.2 g (1 mol) of 1,5-pentanediamine (from Cathay Biotech) with vigorous stirring, and the volatile components were subsequently removed at 80 °C and a vacuum of 10 mbar. This yielded 286.0 g of N,N'-dibenzylidene-1,5-pentanediamine as a clear, yellowish liquid with a viscosity of < 0.05 Pa s at 20 °C, an amine number of 403 mg KOH / g, and an aldimine equivalent weight of 139.2 g / eq.

[0162] Aldimine L-3:

[0163] 212.2 g (2 mol) of benzaldehyde were introduced under a nitrogen atmosphere, with thorough stirring with a mixture of 51.1 g (0.5 mol) of 1,5-pentanediamine and

[0164] 58.1 g (0.5 mol) of 1,6-hexanediamine were added, and the volatile components were subsequently removed at 80 °C and 10 mbar vacuum. This gave 289.8 g of a clear, yellowish liquid with a viscosity at 20 °C of 0.09 Pa s, an amine number of 393 mg KOH / g, and an aldimine equivalent weight of

[0165] 142.7 g / eq.

[0166] Aldimine L-4:

[0167] 106.1 g (1 mol) of benzaldehyde was placed under a nitrogen atmosphere, and 148.3 g (1 mol NH2) of polyoxypropylenediamine with an average molecular weight of 297 g / mol (a mixture of 81.6 g of Jeffamine® D-230 and 66.7 g of Jeffamine® D-400, both from Huntsman) were added while stirring. The volatile components were then removed at 80 °C and a vacuum of 10 mbar. A clear, yellowish liquid with a viscosity of 0.28 Pa s at 20 °C and a calculated aldimine equivalent weight of 236 g / eq was obtained.

[0168] Aldimine L-5:

[0169] 49.25 g (0.3 mol) of methyl 4-formylbenzoate were ground in a mortar and stirred under a nitrogen atmosphere. 34.5 g (0.3 mol NH2) of polyoxypropylenediamine with an average molecular weight of 230 g / mol (Jeffamine® D-230 from Huntsman) were added, followed by evaporation of the volatile components at 90 °C and a vacuum of 10 mbar. A clear, yellowish liquid with a viscosity of 25.3 Pa s at 20 °C and a calculated aldimine equivalent weight of 261 g / eq was obtained.

[0170] Aldimine L-6:

[0171] 423.1 g (2.8 mol) of 3-nitrobenzaldehyde were ground in a mortar, mixed with 221.6 g (2.8 mol NH2) of 2,2(4),4-trimethyl-1,6-hexanediamine (Vestamin® TMD from Evonik) under a nitrogen atmosphere and with stirring, and the volatile components were subsequently removed at 90 °C and a vacuum of 10 mbar. A clear, yellow-brown liquid with a viscosity of 50.1 Pa s at 20 °C and a calculated aldimine equivalent weight of 212 g / eq was obtained.

[0172] Production of curable compositions:

[0173] Compositions Z-1 to Z-32:

[0174] For each example, the ingredients of component K1 listed in Tables 1 to 5 were mixed in the specified amounts (in parts by weight) and stored in a sealed container.

[0175] Furthermore, the ingredients of component K2 listed in Tables 1 to 5 were mixed in the specified quantities (in parts by weight) and stored in a sealed container.

[0176] Subsequently, components K1 and K2 of each composition were mixed using a centrifugal mixer (Thinky ARE-250, 2000 rpm, 60 s) and tested as described below. The gelation time (the time between mixing the components and gelation) was determined by agitating 10 g of the mixed composition with a spatula at regular intervals until the mass gelled.

[0177] To determine the mechanical properties, the composition was cast onto a PTFE-coated foil to form a 2 mm thick film. This film was cured by storage for 14 days under standard conditions. Several dumbbell-shaped test specimens (length 75 mm, web length 30 mm, web width 4 mm) were punched from the film and tested according to DIN EN 53504 at a tensile speed of 200 mm / min for maximum tensile strength, elongation at break, and 5% elastic modulus (between 0.5-5% elongation). Furthermore, several test specimens were punched out to determine tear resistance and tested according to DIN ISO 34-1, Method B (angular test specimen) at a tensile speed of 500 mm / min.

[0178] The Shore A or D hardness was determined according to DIN 53505 on cylindrical test specimens (diameter 20 mm, thickness 5 mm) after a storage period of 14 days in standard climate.

[0179] The Tg value (glass transition temperature) was determined by DMTA measurement on strip-shaped samples (length 75 mm, width 10 mm, thickness 2 mm), which were stored for 14 d in standard climate, measurement in shear mode with 10 Hz excitation frequency in the temperature range from -80 to 120 °C at a heating rate of 5 K / min under determination of the complex elastic modulus, whereby a maximum in the curve for the loss angle tan δ was read as the Tg value.

[0180] During application and curing of the inventive examples, no aldehyde odor was detectable. Odorless, non-sticky films with a flawless, smooth, and glossy surface were formed.

[0181] The results are shown in Tables 1 to 5.

[0182] The examples marked with “(Ref.)” are comparative examples.

[0183]

[0184] Table 1 : Composition and properties of Z-1 to Z-8.

[0185] 1 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0186] "nb" stands for "not determined"

[0187]

[0188] Table 2: Composition and properties of Z-9 to Z-14.

[0189] 1 Diketimine from isophoronediamine and methylisobutyl ketone

[0190] 2 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0191] 3 not measurable (does not harden)

[0192] "nb" stands for "not determined"

[0193]

[0194] Table 3: Composition and properties of Z-15 to Z-20.

[0195] 1 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0196] "nb" stands for "not determined"

[0197]

[0198] Table 4: Composition and properties of Z-21 to Z-26.

[0199] 1 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0200] 2 An elastic film with high tear resistance was obtained without determining the values

[0201] "nb" stands for "not determined"

[0202]

[0203] Table 5: Composition and properties of Z-27 to Z-32.

[0204] 1 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0205] 2 not measurable (no curing)

[0206] 3 not measurable (sticky and too soft)

[0207] It can be seen from Table 5 that the non-inventive compositions Z-27, Z-28 and Z-32 with a ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II) outside the inventive range did not cure to a usable polymer.

Claims

Patent claims: 1 . Curable composition comprising - at least one polyester polymer A containing ketoester groups of formula (I) which has an average functionality of at least 2 and an average equivalent weight of at least 400 g / eq with respect to these reactive groups, - at least one compound B containing ketoester groups of formula (I) which has an equivalent weight of 114 to 250 g / eq with respect to these reactive groups, OO -o AR (l) where R is a monovalent hydrocarbon radical having 1 to 10 C atoms, and - at least one aldimine L having aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq, — N^'Z ÖD where Z is an aromatic or heteroaromatic five- or six-membered ring which is optionally substituted and / or fused and comprises a total of 4 to 25 C atoms, the weight ratio between compounds B and polyester polymers A being 25 / 75 to 85 / 15, and the ratio between the number of ketoester groups of the formula (I) and the number of aldimine groups of the formula (II) in the entire composition being 2 to 3.

2. Composition according to claim 1, characterized in that R is methyl and the ketoester groups of formula (I) thus represent acetoacetate groups.

3. Composition according to one of claims 1 to 2, characterized in that the polyester polymer A has an average functionality of 2 to 3 and an average equivalent weight of 400 to 2,500 g / eq, in particular 450 to 1,500 g / eq.

4. Composition according to one of claims 1 to 3, characterized in that the polyester polymer A is derived from an amorphous polyester polyol which is liquid at room temperature.

5. Composition according to one of claims 1 to 3, characterized in that the polyester polymer A is a reaction product of castor oil.

6. Composition according to one of claims 1 to 3, characterized in that the polyester polymer A is an amorphous polyester from the esterification of a dimer fatty acid or trimer fatty acid or a dimer fatty alcohol or trimer fatty alcohol.

7. Composition according to one of claims 1 to 6, characterized in that the polyester polymer A is liquid at room temperature.

8. Composition according to one of claims 1 to 7, characterized in that the compound B is selected from the list consisting of 1,4-butanediol diacetoacetate, 2-methyl-1,3-propanediol diacetoacetate, 1,5-pentanediol diacetoacetate, neopentylglycol diacetoacetate, 1,6-hexanediol diacetoacetate, 3-methyl-1,5-pentanediol diacetoacetate, 2-ethyl-1,3-hexanediol diacetoacetate, isosorbide diacetoacetate, 4,4'-isopropylidene-bis(cyclohexanol)diacetoacetate, glycerol diacetoacetate, glycerol triacetoacetate, 1,1,1-trimethylolethane diacetoacetate, 1,1,1-trimethylolethane triacetoacetate, 1,1,1-trimethylolpropane diacetoacetate, 1,1,1-trimethylolpropane triacetoacetate and the triacetoacetate of propoxylated 1,1,1-trimethylolpropane with a total average molecular weight Mn of 500 to 750 g / mol.

9. Composition according to one of claims 1 to 8, characterized in that Z is phenyl.

10. Composition according to one of claims 1 to 9, characterized in that the aldimine L is an aldimine of formula (III), where n is 2 or 3 and G is an n-valent organic radical having 2 to 25 C atoms, in particular selected from the list consisting of N,N'-dibenzylidene-1,5-pentanediamine, N,N'-dibenzylidene-1,6-hexanediamine, N,N'-dibenzylidene-2-methyl-1,5-pentanediamine, N,N'-dibenzylidene-2,2(4),4-trimethyl-1,6-hexanediamine, N,N'-dibenzylidene-1,3-bis(aminomethyl)cyclohexane, N,N'-dibenzylidene-1,3-bis(aminomethyl)benzene, N,N'-dibenzylideneisophoronediamine, N,N'-dibenzylidene-4,4'-methylene-bis(cyclohexylamine), N,N'-dibenzylidenepolyoxy- propylenediamines with medium molecular weight M n from 350 to 750 g / mol and N,N',N"-tribenzylidenepolyoxypropylenetriamines with medium molecular weight M nfrom 450 to 700 g / mol, as well as the analogous aldimines derived from 4-formylbenzoic acid methyl ester, 4-formylbenzoic acid ethyl ester, 3-nitrobenzaldehyde, tolualdehyde, 4-methoxybenzaldehyde, furfural, 5-methylfurfural and 5-hydroxymethylfurfural instead of benzaldehyde.

11. Composition according to one of claims 1 to 10, characterized in that, based on the total composition, less than 10% by weight, preferably less than 5% by weight, in particular less than 1% by weight, of volatile organic compounds (VOC) having a boiling point at atmospheric pressure of less than 250 °C, in particular organic solvents, are present.

12. Composition according to one of claims 1 to 11, characterized in that the composition comprises a component K1 and a component K2, which are each storage-stable on their own and are stored in separate containers, compounds having ketoester groups of the formula (I) being a component of component K1 and aldimines having aldimine groups of the formula (II) being a component of component K2. Settling according to a claim in DIS IZ after mixing the ingredients or components and subsequent curing.

14. Cured composition according to claim 13, characterized in that the elongation at break is at least 5%, preferably at least 10%, particularly preferably at least 20%, in particular at least 40%, determined according to DIN EN 53504 on dumbbell-shaped test specimens (length 75 mm, web length 30 mm, web width 4 mm, thickness 2 mm) with a tensile speed of 200 mm / min, and that the tear propagation resistance is at least 20 N / mm, in particular at least 40 N / mm, determined according to DIN ISO 34-1 method B (angular test specimen) with a sample thickness of 2 mm and a tensile speed of 500 mm / min.

15. Use of the curable composition according to any one of claims 1 to 12 as an adhesive, sealant or coating, wherein the ingredients or components are mixed together and the mixed composition is applied in the liquid state to at least one substrate.

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