Curable compositions containing functional polyethers and aldimines

Abstract

The invention relates to a curable composition comprising: at least one polyether polymer A with ketoester groups of formula (I) or aldimine groups of formula (II), having an average functionality of 1.7 to 3.0 and an average equivalent weight of at least 500 g / eq; at least one compound B with ketoester groups of formula (I) and an equivalent weight of 114 to 250 g / eq; and at least one aldimine L with aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq, 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 an elastic polymer with high extensibility and surprisingly high tear resistance. The composition is particularly suitable as an elastic adhesive, sealant, or coating.

Description

[0001] Curable compositions containing functional polyethers and aldimines

[0002] Technical area

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

[0004] State of the art

[0005] Curable polymer compositions that achieve elastic properties and can be used, for example, as adhesives, sealants or coatings are known.

[0006] Particularly interesting are highly elastic systems that exhibit high strength and ductility, yet lack a pronounced glass transition temperature (Tg) at the service temperature, especially between approximately -40 and 80 °C, and thus possess largely temperature-independent mechanical properties. Such properties are particularly well known for polyurethanes or systems closely related to polyurethanes, such as urethane-containing silane-curing systems, which are manufactured using isocyanates. Isocyanates are toxic and moisture-sensitive substances whose handling requires considerable technical expertise and protective measures.

[0007] Curable compositions containing acetoacetate groups as reactive groups are also known. However, these usually result in hard, low-extensibility, and barely elastic polymers. Furthermore, many of these systems contain large amounts of volatile organic solvents, which produce undesirable emissions during curing.

[0008] US 5,288,804 describes solvent-based coatings based on acetoacetate-functional acrylate polymers, which are cured using 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 using aliphatic ketimines. These compositions are not elastic and lead to strong emissions. US 6,204,343 describes curable compositions based on acetoacetate-functional polyols, which are cured with acrylates, for embedding electrical components. These compositions are also not elastic.

[0009] Description of the invention

[0010] The object of the present invention is to provide a room temperature curable polymer composition which enables elastic products with good strength and high extensibility and overcomes the disadvantages of the prior art with regard to toxic ingredients, moisture sensitivity and emissions.

[0011] Surprisingly, this object is achieved with a curable composition as described in claim 1. The composition comprises at least one polyether polymer A having ketoester groups of the formula (I) or aldimine groups of the formula (II), at least one compound B having ketoester groups of the formula (I) and at least one aldimine L having aldimine groups of the formula (II), wherein the ratio between the number of ketoester groups of the formula (I) and the number of aldimine groups of the 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-tacky polymer with excellent mechanical properties. Despite the absence of urethane groups, a high-quality crosslinked elastic polymer with high strength and extensibility and surprisingly high tear resistance is formed. 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 at room temperature and requiring no solvents for dilution. 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 is incorporated into the polymer and thus remains permanently in the cured composition.

[0013] In a preferred embodiment, cured polymers are produced that exhibit no glass transition (Tg) in the temperature range from -20 to 60 °C, especially from -40 to 80 °C. Such elastic polymers with high tear resistance and largely temperature-independent properties are extremely surprising, especially because they are obtained without urethane groups and thus without the use of isocyanates.

[0014] The composition according to the invention is particularly suitable for use as an adhesive, sealant or coating, in particular for applications where high elasticity with high tear resistance and largely temperature-independent properties 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.

[0015] 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.

[0016] Ways to implement the invention

[0017] The invention relates to a curable composition comprising

[0018] - at least one polyether polymer A with ketoester groups of formula (I) or aldimine groups of formula (II), which has an average functionality of 1.7 to 3.0 with respect to these reactive groups and an average equivalent weight of at least 500 g / eq,

[0019] - at least one compound B having ketoester groups of formula (I) which has an equivalent weight of 114 to 250 g / eq with respect to these reactive groups, and

[0020] - at least one aldimine L having aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq,

[0021] — N^Z CD where R is a monovalent hydrocarbon radical having 1 to 10 C atoms and 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, and where 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 is 2 to 3.

[0022] A dashed line in the formulas in this document represents the bond between a substituent and the corresponding molecular residue. 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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, a polymer with particularly good mechanical properties is 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 2.2 to 2.7, in particular approximately 2.5.

[0027] The polyether polymer A preferably has an average equivalent weight of 500 to 6,000 g / eq.

[0028] The polyether polymer A particularly preferably has an average equivalent weight of 1,000 to 6,000 g / eq, in particular 1,500 to 3,000 g / eq.

[0029] Such a composition enables cured polymers that exhibit no glass transition temperature (Tg) in the temperature range from -20 to 60 °C, especially from -40 to 80 °C. Such polymers enable a particularly wide range of service temperatures for bonded, sealed, or coated articles, in which the mechanical properties are largely temperature-independent.

[0030] Preferably, the polyether polymer A has an average molecular weight M n from 1,000 to 15,000 g / mol, particularly preferably 2,000 to 10,000 g / mol, in particular 3,000 to 6,000 g / mol.

[0031] Preferably, the polyether polymer A has an average functionality of 1.8 to 3.0, especially 1.8 to 2.0. This enables elastic polymers with particularly high elongation and elasticity.

[0032] The polyether polymer A preferably contains repeating units selected from the list consisting of oxy-1,2-propylene, oxy-1,3-propylene, oxy-1,4-butylene, oxy-1,2-butylene, and oxyphenylethylene. Additionally, the polyether polymer A may have a certain content of oxyethylene units, in particular a maximum of 25% by weight of oxyethylene based on the total weight of the polyether units.

[0033] Particularly preferred are oxy-1,2-propylene or oxy-1,4-butylene. Oxy-1,2-propylene is most preferred.

[0034] Particularly preferred as polyether polymer A is a poly(oxy-1,2-propylene) polymer, in particular a linear poly(oxy-1,2-propylene) polymer or a branched poly(oxy-1,2-propylene) polymer, which is started in particular on 1,1,1-trimethylolpropane or on glycerol.

[0035] Most preferred as polyether polymer A is a linear poly(oxy-1,2-propylene) polymer.

[0036] Preferably, the polyether polymer A is liquid and low-viscosity at room temperature. In particular, it has a viscosity at 20 °C of 0.1 to 10 Pa s, preferably 0.1 to 5 Pa s, in particular 0.2 to 2.5 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 , for viscosities of less than 0.5 Pa s with cone diameter of 50 mm and shear rate of 100 s -1Such a polymer is very easy to handle at ambient temperatures, even without the addition of solvents or thinners, and enables very easy-to-process compositions.

[0037] Preferably, R in the ketoester groups of the formula (I) is methyl, ethyl, propyl, isopropyl, butyl or phenyl, in particular methyl or phenyl.

[0038] Particularly preferably, R represents methyl, and the ketoester groups of formula (I) thus represent acetoacetate groups. Polyether polymers A and compounds B containing acetoacetate groups are particularly easily accessible and enable compositions with particularly rapid curing.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] Most preferably, Z is phenyl. These aldimines are derived from benzaldehyde. They are particularly readily available and allow for particularly rapid curing.

[0043] 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.

[0044] The polyether polymer A particularly preferably contains ketoester groups of formula (I). Such a polyether polymer A is particularly easily accessible, has low viscosity, and enables rapid curing and the described advantageous mechanical properties.

[0045] A polyether polymer A having ketoester groups of the formula (I) is preferably obtained from the transesterification of at least one polyether 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.

[0046] 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 1 OH and optionally fragmentation products thereof, optionally under vacuum and optionally in the presence of a suitable catalyst.

[0047] It is also possible to produce the polyether polyol by reacting it 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.

[0048] Preferred polyether polyols are poly(oxy-1,2-propylene)diols or poly(oxy-1,2-propylene)triols, which may optionally contain up to 25% by weight of oxy-1,2-ethylene units at the chain ends, poly(oxy-1,3-propylene)diols or triols, or poly(oxy-1,4-butylene)diols, which are also referred to as polytetrahydrofurans. Most preferred is a poly(oxy-1,2-propylene)diol with an OH number of 14 to 112 mg KOH / g, preferably 14 to 56 mg KOH / g, particularly preferably 19 to 40 mg KOH / g, in particular with an OH number of approximately 28 mg KOH / g.

[0049] Particularly preferred as polyether polymer A with ketoester groups of the formula (I) is therefore a poly(oxy-1,2-propylene)diol diacetoacetate with an average equivalent weight of 1,000 to 5,000 g / eq, preferably 1,500 to 3,000 g / eq.

[0050] In one embodiment of the invention, the polyether polymer A contains aldimine groups of formula (II). Such a polyether polymer A is in particular derived from a polyether diamine or triamine. Surprisingly, such a polyether polymer A enables largely the same mechanical properties and glass transition temperatures as when using a corresponding polyether polymer A with ketoester groups of formula (I).

[0051] Preferred polyether polymers A having aldimine groups of formula (II) are N,N'-dibenzylidene-poly(oxy-1,2-propylene)diamines or N,N',N"-tribenzylidene-poly(oxy-1,2-propylene)triamines derived from Jeffamine® D-2000, Jeffamine® D-4000 or Jeffamine® T-5000 (all from Huntsman) or corresponding polyetheramines from BASF or Nitroil.

[0052] Particularly preferred as polyether polymer A with aldimine groups of the formula (II) is N,N'-dibenzylidene-poly(oxy-1,2-propylene)diamine with an average equivalent weight of 1,000 to 3,000 g / eq, preferably 1,500 to 3,000 g / eq.

[0053] 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.

[0054] Preferably, compound B has two to four, in particular two to three, ketoester groups of formula (I).

[0055] Preferably, compound B has an equivalent weight of 114 to 200 g / eq. 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 polyether polymer A having ketoester groups of formula (I).

[0056] 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 200 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.

[0057] Preferred are 1,2-propanediol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 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, polytetrahydrofurandiol with medium molecular weight M nfrom 200 to 300 g / mol, 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.

[0058] Preferably, compound B is selected from the list consisting of 1,2-propanediol diacetoacetate, dipropylene glycol diacetoacetate, tripropylene glycol diacetoacetate, 1,3-propanediol diacetoacetate, 1,4-butanediol diacetoacetate, 2-methyl-1,3-propanediol diacetoacetate, 1,5-pentanediol diacetoacetate, neopentyl glycol 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, polytetrahydrofuran diacetoacetate with medium molecular weight M nfrom 350 to 450 g / mol, 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.

[0059] Of these, preferred are diacetoacetates, in particular 1,2-propanediol diacetoacetate, dipropylene glycol diacetoacetate, tripropylene glycol diacetoacetate, 1,3-propanediol diacetoacetate, 1,4-butanediol diacetoacetate, 2-methyl-1,3-propanediol diacetoacetate, 1,5-pentanediol diacetoacetate, neopentyl glycol diacetoacetate, 1,6-hexanediol diacetoacetate, 3-methyl-1,5-pentanediol diacetoacetate, 2-ethyl-1,3-hexanediol diacetoacetate or polytetrahydrofurandiol with medium molecular weight M n from 200 to 300 g / mol.

[0060] Neopentylglycol diacetoacetate is particularly preferred. This produces polymers with particularly high strength and water resistance.

[0061] 3-Methyl-1,5-pentanediol diacetoacetate is also particularly preferred. This produces polymers with particularly high strength and water resistance.

[0062] 2-Ethyl-1,3-hexanediol diacetoacetate is also particularly preferred. This produces polymers with particularly high strength and water resistance.

[0063] The weight ratio between compounds B and polyether polymers A is preferably in the range of 15 / 85 to 85 / 15, preferably 20 / 80 to 80 / 20, in particular 25 / 75 to 75 / 25. This results in elastic polymers with good strength, high extensibility, and high tear resistance, with a high content of polyether polymer A enabling more flexible properties and a high content of compound B enabling higher strengths.

[0064] In case the curable composition contains an aldimine L derived from a polyetherdiamine or polyethertriamine, the weight ratio between compounds B and polyether polymers A is preferably in the range of 30 / 70 to 95 / 5, in particular 50 / 50 to 90 / 10.

[0065] 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.

[0066] The aldimine L preferably has one to three, in particular two to three, aldimine groups of the formula (II).

[0067] Preferred as aldimine L is an aldimine of formula (III), where n is 2 or 3 and G is an n-valent organic radical with 2 to 25 C-

[0068] atoms and Z has the meanings already mentioned.

[0069] Preferably, G represents a divalent hydrocarbon radical having 5 to 15 C atoms or a di- or trivalent polyoxyalkylene radical having an average molecular weight Mn of 160 to 500 g / mol.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] Preferred aromatic or heteroaromatic aldehydes are benzaldehyde,

[0074] 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,

[0075] 2,4-Dimethoxybenzaldehyde, 2,5-Dimethoxybenzaldehyde, 3,4-Dimethoxybenzaldehyde, 3,5-Dimethoxybenzaldehyde, 4-Hydroxy-3-methoxybenzaldehyde (vanillin), 2,4,6-Trimethylbenzaldehyde, 2,4,5-Trimethoxybenzaldehyde, 2,4,6-T rimethoxy-benzaldehyde, 3,4,5-trimethoxybenzaldehyde, 4-formylbenzoic acid ester, in particular 4-formylbenzoic acid methyl ester or 4-formylbenzoic acid ethyl ester,

[0076] 3-nitrobenzaldehyde, 1-naphthaldehyde, 2-naphthaldehyde, furfural, 5-methylfurfural or 5-hydroxymethylfurfural..

[0077] Particularly preferred is benzaldehyde, methyl 4-formylbenzoate, ethyl 4-formylbenzoate, 3-nitrobenzaldehyde, tolualdehyde, 4-methoxybenzaldehyde, furfural, 5-methylfurfural or 5-hydroxymethylfurfural, in particular benzaldehyde, methyl 4-formylbenzoate, 3-nitrobenzaldehyde, furfural or 5-methylfurfural.

[0078] Benzaldehyde is most preferred.

[0079] 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.

[0080] 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 Mn 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.

[0081] 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 an average molecular weight Mn of 350 to 750 g / mol, and mixtures thereof with another aldimine of the formula (III). These aldimines or aldimine mixtures have little tendency to crystallize and are typically permanently liquid at room temperature. Very particular preference is given to N,N'-dibenzylidene-1,5-pentanediamine. This results in particularly high strengths and polymers cured with it show a particularly wide range without a glass transition temperature with a particularly high upper glass transition temperature.

[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 700 g / mol, especially 400 to 750 g / mol. This results in particularly good extensibility and toughness.

[0084] Preferably, polyether 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, - pigments, in particular titanium dioxide, chromium oxide, iron oxides or organic pigments,

[0090] - 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,

[0091] - Catalysts for the reaction of 1,3-ketoester groups with aldimine groups,

[0092] - solvents,

[0093] - Modifiers such as hydrocarbon resins, natural or synthetic waxes or bitumen,

[0094] - Rheology modifiers, in particular urea compounds, layered silicates 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. 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 compounds 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 commencing curing.

[0103] 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.

[0104] The consistency of component K1 and component K2 is suitable for mixing the components well under ambient conditions using simple methods. Liquid or pasty components are particularly suitable for this purpose.

[0105] Components K1 and K2 of the curable composition are manufactured separately. The ingredients of each component are mixed together to create a macroscopically homogeneous mass. Components K1 and K2 are each stored in separate containers. Suitable containers include 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 mixing 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 harden due to the chemical reaction that occurs.

[0111] It can be assumed that typically two ketoester groups of formula (I) 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 suggests 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.

[0112] 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. Another subject 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 high extensibility, high tensile strength, high tear resistance and low temperature dependence of the mechanical properties.

[0114] The cured composition preferably has an elongation at break of at least 25%, preferably at least 50%, in particular at least 100%, 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 tensile strength of at least 1.5 MPa, preferably at least 3 MPa, in particular at least 5 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.

[0116] The cured composition preferably has a tear resistance of at least 2.5 N / mm, preferably at least 5 N / mm, particularly preferably at least 10 N / mm, in particular at least 15 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.

[0117] The cured composition preferably has no glass transition temperature (Tg) in the temperature range from -20 to 60°C, preferably -35 to 70°C, in particular -40 to 80°C, as 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 modulus of elasticity, with a maximum in the loss angle curve being read off as the Tg value. The curable composition is suitable for a variety of applications. It is used in particular as an adhesive, sealant, coating, casting resin or filler, in particular as an elastic adhesive, sealant or coating.

[0118] A further object of the invention is the use of the curable composition as an elastic adhesive, elastic sealant or elastic coating, wherein the ingredients or components are mixed together and the mixed composition is applied in the liquid state to at least one substrate.

[0119] Suitable substrates include:

[0120] - Glass, glass ceramics, concrete, mortar, cement screed, fiber cement, brick, tile, plaster or natural stones such as granite or marble;

[0121] - Repair or levelling compounds based on PCC (polymer-modified cement mortar) or ECO (epoxy resin-modified cement mortar);

[0122] - Metals or alloys such as aluminum, iron, steel, copper, other non-ferrous metals, including surface-treated metals or alloys such as galvanized or chrome-plated metals;

[0123] - asphalt or bitumen;

[0124] - 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;

[0125] - 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;

[0126] - 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);

[0127] - insulating materials, in particular foams, in particular made of EPS, XPS, PUR, PIR, aerogel or foamed glass (foam glass), or fibres made of rock wool or glass wool, - coated or painted substrates, in particular painted tiles, painted concrete, powder-coated metals or alloys or painted sheets;

[0128] - Coatings, paints or varnishes.

[0129] 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.

[0130] Two similar or two different substrates can be bonded and / or sealed.

[0131] 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.

[0132] Description of the pictures:

[0133] Figure 1 shows the curve of the complex elastic modulus and the loss angle of the composition Z-2 vs. the temperature with the Tg values.

[0134] Figure 2 shows the curve of tensile stress vs. strain of several test specimens of composition Z-2.

[0135] Figure 3 shows the curve of the complex elastic modulus and the loss angle of the composition Z-5 vs. the temperature with the Tg values.

[0136] Figure 4 shows the curves of tensile stress versus strain for several test specimens of composition Z-5. Figure 5 shows the curves of the complex elastic modulus and loss angle of composition Z-14 versus temperature with the Tg values.

[0137] Figure 6 shows the curve of tensile stress vs. strain of several test specimens of composition Z-14.

[0138] Figure 7 shows the curve of the complex elastic modulus and the loss angle of the composition Z-4 vs. the temperature with the Tg values.

[0139] Figure 8 shows the curve of tensile stress vs. strain of several test specimens of composition Z-4.

[0140] Examples

[0141] The following are exemplary embodiments intended to further illustrate the described invention. Of course, the invention is not limited to these described exemplary embodiments.

[0142] The “standard climate” (“NK”) is defined as a temperature of 23±1 °C and a relative humidity of 50±5%.

[0143] Unless otherwise stated, the chemicals used were from Merck.

[0144] 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.

[0145] 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.

[0146] Production of polyether polymers with ketoester groups or aldimine groups: Polymer P-1 :

[0147] 1,000 g (0.5 mol OH) of polyoxypropylenediol (Acclaim® 4200, OH number 28 mg KOH / g, from Covestro) was mixed with 87.0 g (0.55 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. 1033.7 g of a clear, slightly yellowish liquid with a viscosity at 20 °C of 1.15 Pa s, an acetoacetate functionality of 2, and a theoretical acetoacetate equivalent weight of 2084 g / eq were obtained.

[0148] Polymer P-2:

[0149] 500 g (0.5 mol OH) of polyoxypropylenediol (Voranol ® 2000 L, OH number 56 mg KOH / g, from Dow) was treated with 71.6 g (0.55 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. 540.4 g of a clear, slightly yellowish liquid with a viscosity at 20 °C of 0.47 Pa s, an acetoacetate functionality of 2, and a theoretical acetoacetate equivalent weight of 1084 g / eq were obtained.

[0150] Polymer P-3:

[0151] 500 g (1 mol OH) of polyoxypropylenediol (Voranol® 1010 L, OH number 112 mg KOH / g, from Dow) was mixed with 143.1 g (1.1 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 -1had disappeared and no more volatiles were separated. 558.9 g of a clear, colorless liquid with an acetoacetate functionality of 2 and a theoretical acetoacetate equivalent weight of 584 g / eq were obtained.

[0152] Polymer P-4:

[0153] 500 g (2.2 mol OH) of polyoxypropylenediol (Voranol® P 400, OH number 250 mg KOH / g, from Dow) was mixed with 312 g (2.4 mol) of ethyl acetoacetate and 0.8 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 volatiles were deposited. 657.6 g of a clear, colorless liquid with a viscosity at 20 °C of 0.11 Pa s, an acetoacetate functionality of 2, and a theoretical acetoacetate equivalent weight of 308 g / eq were obtained.

[0154] Polymer P-5:

[0155] 400.0 g (0.2 mol NH2) of polyoxypropylenediamine (Jeffamine® D-4000, from Huntsman) was placed under a nitrogen atmosphere, mixed with 21.2 g (0.2 mol) of benzaldehyde with vigorous stirring, and the volatile components were then removed at 80 °C and a vacuum of 10 mbar. This yielded 417.6 g of a clear, yellowish liquid with an amine number of 26.87 mg KOH / g and an aldimine equivalent weight of 2088 g / eq.

[0156] Polymer P-6:

[0157] 800 g (0.5 mol OH) of polyoxypropylenetriol (Voranol® CP 4755, OH number 35 mg KOH / g, OH functionality approx. 2.4, from Dow) was mixed with 87.0 g (0.55 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. This yielded 833.7 g of a clear, slightly yellowish liquid with a viscosity at 20 °C of 1.19 Pa s, an acetoacetate functionality of approximately 2.4, and a theoretical acetoacetate equivalent weight of 1687 g / eq.

[0158] Polymer P-7:

[0159] 300 g (0.3 mol OH) of poly(oxy-1,4-butylene)diol (Terathane® 2000 PTMEG, OH number 56 mg KOH / g, from Invista) was treated with 43.0 g (0.33 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. 321.7 g of a clear, slightly yellowish liquid with an acetoacetate functionality of 2 and a theoretical acetoacetate equivalent weight of 1084 g / eq were obtained.

[0160] Preparation of compounds with ketoester groups:

[0161] Neopentylglycol diacetoacetate (AA-NPG): 104.1 g (1 mol) of neopentylglycol (= 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 was observed in the FT-IR. -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

[0162] 136 g / eq.

[0163] 1,2-Propanediol diacetoacetate (AA-PG):

[0164] 76.1 g (1 mol) of 1,2-propanediol 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' was observed in the FT-IR. 1 had disappeared and no more volatiles were separated. 237.8 g of 1,2-propanediol 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 122 g / eq.

[0165] 3-Methyl-1,5-pentanediol diacetoacetate (AA-M5D):

[0166] 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. -1had 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.

[0167] 2-Ethyl-1,3-hexanediol diacetoacetate (AA-EHD):

[0168] 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. -1 had 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.

[0169] Production of aldimines:

[0170] Aldimine D-1 :

[0171] 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.

[0172] Aldimine D-2:

[0173] 212.2 g (2 mol) of benzaldehyde were initially charged under a nitrogen atmosphere, mixed with a mixture of 51.1 g (0.5 mol) of 1,5-pentanediamine and 58.1 g (0.5 mol) of 1,6-hexanediamine with vigorous stirring, and the volatile components were then removed at 80 °C and a vacuum of 10 mbar. This yielded 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 142.7 g / eq.

[0174] Aldimine D-3:

[0175] 212.2 g (2 mol) of benzaldehyde were initially charged under a nitrogen atmosphere, mixed with 116.2 g (1 mol) of 1,5-diamino-2-methylpentane (Dytek® A, from Invista) with vigorous stirring, and the volatile components were then removed at 80 °C and a vacuum of 10 mbar. 268.2 g of N,N'-dibenzylidene-1,5-diamino-2-methylpentane were obtained as a clear, yellowish liquid with an amine number of 379 mg KOH / g and an aldimine equivalent weight of 148 g / eq.

[0176] Aldimine D-4:

[0177] 212.2 g (2 mol) of benzaldehyde were initially charged under a nitrogen atmosphere, admixed with 158.3 g (1 mol) of 2,2(4),4-trimethyl-1,6-hexanediamine (Vestamin® TMD, from Evonik) with vigorous stirring, and the volatile components were subsequently removed at 80 °C and a vacuum of 10 mbar. This yielded 333.6 g of N,N'-dibenzylidene-2,2(4),4-trimethyl-1,6-hexanediamine as a clear, yellowish liquid with an amine number of 335 mg KOH / g and an aldimine equivalent weight of 167.3 g / eq. The liquid crystallized to a solid at room temperature within a few weeks.

[0178] Aldimine D-5:

[0179] 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.

[0180] Aldimine D-6:

[0181] 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.

[0182] Production of curable compositions:

[0183] Compositions Z-1 to Z-35:

[0184] 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.

[0185] Furthermore, the ingredients of component K2 listed in Tables 1 to 5 were mixed in the specified amounts (in parts by weight) and stored in a sealed container. 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.

[0186] The gelling time (time between mixing the components and gelling) was determined by moving 10 g of the mixed composition with a spatula at regular intervals until the mass gelled.

[0187] To determine the mechanical properties, the composition was poured onto a PTFE-coated foil to form a film of 2 mm thickness, which was cured by storage for 14 days under standard climate, some 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 modulus of elasticity 5% (between 0.5-5% elongation).

[0188] Figures 2, 4, and 6 show the tensile stress versus strain curves of several test specimens of compositions Z-2, Z-5, and Z-14. Furthermore, several test specimens were punched out of the 2 mm thick film to determine the tear resistance and tested according to DIN ISO 34-1, Method B (angular test specimen) at a tensile speed of 500 mm / min.

[0189] 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.

[0190] 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.

[0191] Figures 1, 3, and 5 show the DMTA curves with the Tg values ​​of the compositions Z-2, Z-5, and Z-14. The upper curve shows the course of the complex elastic modulus, and the lower curve shows the course of the loss angle "tan δ" vs. temperature.

[0192] During application and curing of the compounds, no aldehyde odor was detectable. Odorless, non-sticky films were formed.

[0193] The results are shown in Tables 1 to 5.

[0194] The examples marked with “(Ref.)” are comparative examples.

[0195] Table 1 : Composition and properties of Z-1 to Z-8.

[0196] 1 Neopentylglycol diacetoacetate

[0197] 2 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0198] "nb" stands for "not determined"

[0199] Table 2: Composition and properties of Z-9 to Z-15.

[0200] 1 Neopentylglycol diacetoacetate

[0201] 2 Diketimine from isophoronediamine and methylisobutyl ketone

[0202] 3Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0203] 4 Ratio of the number of ketoester groups of formula (I) to the number of ketimine groups

[0204] 5 not measurable (does not harden)

[0205] "nb" stands for "not determined"

[0206]

[0207] Table 3: Composition and properties of Z-16 to Z-22.

[0208] 1 Neopentylglycol diacetoacetate

[0209] 2 1,2-Propanediol diacetoacetate

[0210] 3 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0211] "nb" stands for "not determined"

[0212]

[0213] Table 4: Composition and properties of Z-23 to Z-29.

[0214] 1 Neopentylglycol diacetoacetate

[0215] 2 3-Methyl-1,5-pentanedioldiacetoacetate

[0216] 3 2-Ethyl-1,3-hexanedioldiacetoacetate

[0217] 4 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0218] 5 sticky

[0219] 6 not measurable, no curing

[0220] "nb" stands for "not determined"

[0221]

[0222] Table 5: Composition and properties of Z-30 to Z-35.

[0223] 1 2-Ethyl-1,3-hexanedioldiacetoacetate

[0224] 2 3-Methyl-1,5-pentanedioldiacetoacetate

[0225] 3 Neopentylglycol diacetoacetate

[0226] 4 Ratio of the number of ketoester groups of formula (I) to the number of aldimine groups of formula (II)

[0227] "nb" stands for "not determined"

Claims

Patent claims: 1 . Curable composition comprising - at least one polyether polymer A with ketoester groups of formula (I) or aldimine groups of formula (II), which has an average functionality of 1.7 to 3.0 with respect to these reactive groups and an average equivalent weight of at least 500 g / eq, - 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, and - at least one aldimine L having aldimine groups of formula (II) and an aldimine equivalent weight of 110 to 350 g / eq, OO — O AJ R <'> — N^'Z (H) where R is a monovalent hydrocarbon radical having 1 to 10 C atoms and 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, and where 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 is 2 to 3.

2. Composition according to claim 1, characterized in that the polyether polymer A has an average equivalent weight of 1,000 to 6,000 g / eq, preferably 1,500 to 3,000 g / eq.

3. Composition according to claim 1 or 2, characterized in that the polyether polymer A contains repeating units selected from the list consisting of oxy-1,2-propylene, oxy-1,3-propylene, oxy-1,4-butylene, oxy-1,2-butylene and oxyphenylethylene.

4. Composition according to one of claims 1 to 3, characterized in that R represents methyl and the ketoester groups of formula (I) thus represent acetoacetate groups.

5. Composition according to one of claims 1 to 4, characterized in that Z is phenyl.

6. Composition according to one of claims 1 to 5, characterized in that the polyether polymer A has ketoester groups of the formula (I) and is in particular a poly(oxy-1,2-propylene)diol diacetoacetate with an average equivalent weight of 1,000 to 5,000 g / eq, preferably 1,500 to 3,000 g / eq.

7. Composition according to one of claims 1 to 5, characterized in that the polyether polymer A has aldimine groups of the formula (II) and is in particular an N,N'-dibenzylidene-poly(oxy-1,2-propylene)diamine having an average equivalent weight of 1,000 to 3,000 g / eq, preferably 1,500 to 3,000 g / eq.

8. Composition according to one of claims 1 to 7, characterized in that the compound B is selected from the list consisting of 1,2-propanediol diacetoacetate, dipropylene glycol diacetoacetate, tripropylene glycol diacetoacetate, 1,3-propanediol diacetoacetate, 1,4-butanediol diacetoacetate, 2-methyl-1,3-propanediol diacetoacetate, 1,5-pentanediol diacetoacetate, neopentyl glycol 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, polytetrahydrofuran diacetoacetate with medium Molecular weight Mn from 320 to 500 g / mol, 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 M, n from 500 to 750 g / mol.

9. Composition according to one of claims 1 to 8, characterized in that the weight ratio between compounds B and polyether polymers A is in the range from 15 / 85 to 85 / 15, preferably 20 / 80 to 80 / 20, in particular 25 / 75 to 75 / 25.

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 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.

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 part of component K1 and compounds having aldimine groups of the formula (II) being part of component K2.

13. Cured composition obtained from the curable composition according to any one of claims 1 to 12 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 25%, preferably at least 50%, in particular at least 100%, 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.

15. Use of the curable composition according to any one of claims 1 to 12 as an elastic adhesive, elastic sealant or elastic 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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