Curable composition having an aldimine-functional polymer and 1,3-ketoester

Abstract

The invention relates to a curable composition comprising at least one polymer having end groups of formula (I) containing an aromatic aldimine group and an average molecular weight Mn of 1,000 to 30,000 g / mol, and at least one compound having two or more 1,3-ketoester groups of formula (II). The curable composition is not sensitive to moisture, cures quickly and reliably at room temperature when the components are mixed and enables surprisingly high extensibility and surprisingly high tear propagation resistance at high strength and good stability against heat and hydrolysis.

Description

[0001] Hydrogenable composition with aldimine functional polymer and 1,3-ketoester

[0002] Technical field

[0003] The invention relates to room temperature curable elastic adhesives or sealants comprising an aldimine-functional polymer and 1,3-keto ester.

[0004] State of the art

[0005] Reactive polymer compositions that cure at room temperature and can be used as adhesives, sealants, or coatings with elastic properties are well-known. Polyurethane systems, which cure through the reaction of isocyanate groups with polyols and / or moisture, forming particularly highly elastic polymers, are widely used. However, the production and use of polyurethane systems present a number of practical challenges, especially due to the toxicity of the monomeric isocyanates they contain and their high sensitivity to moisture before and during curing.

[0006] US 2018 / 0327535 describes aldimine-functional polymers and their curing using polyisocyanate under the influence of moisture. However, the aforementioned problems with toxic monomers and sensitivity to moisture persist.

[0007] WO 2024 / 012828 describes aldehyde-functional polymers and their curing with 1,3-keto esters. The cured polymers still have room for improvement with regard to elongation and tear resistance.

[0008] US 5,288,804 describes solvent-based coatings based on acetoacetate functional acrylate polymers that cure with aromatic polyaldimines. This process generates high emissions, and the resulting coatings are inelastic and have little elasticity.

[0009] US 5,536,784 describes aqueous coatings made from a combination of acetoacetate-functional and aldimine-functional polyesterurethane dispersions. Such aqueous systems are not suitable for use in high layer thicknesses or between water-impermeable substrates, and the resulting films are not elastic. Description of the invention

[0010] The object of the present invention is to provide a composition that can be cured at room temperature, has high elongation, is suitable as an elastic adhesive or sealant, and overcomes the disadvantages of the prior art with regard to toxic monomers and sensitivity to moisture before and during curing.

[0011] Surprisingly, this problem is solved with a curable composition as described in claim 1. The composition comprises a polymer with end groups of formula (I) and a compound with two or more 1,3-ketoester groups of formula (II). The end group of formula (I) contains an aromatic aldimine group and is bonded to the polymer via a urethane, thiourethane, or urea group, in particular a urethane group. The composition according to the invention contains no toxic monomers and is not sensitive to moisture. Its components are easy to prepare and can be stored for extended periods without special precautions. After mixing the components, the composition cures rapidly and odorlessly at room temperature without the need for added catalysts.The cured composition exhibits surprisingly high elongation and elasticity with high strength and high tear resistance, as well as good stability against heat and hydrolysis.

[0012] Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of dependent claims.

[0013] Ways to implement the invention

[0014] The invention relates to a curable composition comprising - at least one polymer with end groups of formula (I) and an average molecular weight M n from 1,000 to 30,000 g / mol,

[0015]

[0016] where X represents 0, S or NR 1 and R 1 stands for H or a monovalent hydrocarbon residue with 1 to 18 C atoms, and

[0017] A stands for a monovalent organic residue with 7 to 30 carbon atoms, containing an aromatic aldimine group,

[0018] and

[0019] - at least one compound with two or more 1,3-ketoester groups of formula (II),

[0020] OO

[0021] -OAA R2 <">

[0022] where R 2 stands for a monovalent hydrocarbon residue with 1 to 6 carbon atoms.

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

[0024] An “aromatic aldimine group” is a grouping of the formula --N=CH--, whose carbon atom is directly bonded to an aromatic or heteroaromatic ring and which is itself not part of a heteroaromatic ring system.

[0025] The term "molecular weight" refers to the molar mass (in grams per mole) of a molecule. The "mean molecular weight" is the number-average molecular weight M. n It is defined as a polydisperse mixture of oligomeric or polymeric molecules. It is determined by gel permeation chromatography (GPC) against polystyrene as a standard.

[0026] Substance names beginning with "Poly", such as polyol or polyaldimine, denote substances that formally contain two or more of the functional groups appearing in their name per molecule.

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

[0028] All industry standards and norms mentioned in the document refer to the versions valid at the time of the initial application.

[0029] Weight percent (wt%) denotes 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.

[0030] Preferably, the polymer with end groups of formula (I) is liquid at room temperature. In particular, it has a viscosity at 20 °C of 1 to 500 Pa s, particularly preferably 2 to 200 Pa s, and more preferably 3 to 150 Pa s, measured by a cone-plate viscometer with a cone diameter of 10 mm, a cone angle of 1°, a cone-tip-plate distance of 0.05 mm, and a shear rate of 10 s⁻¹. -1 .

[0031] Preferably, the polymer with end groups of formula (I) has an average molecular weight M n from 2,000 to 20,000 g / mol, especially 2,500 to 15,000 g / mol.

[0032] Preferably the polymer with end groups of formula (I) has a mean aldimine functionality of 1.5 to 4, preferably 1.8 to 3, in particular 2 to 3.

[0033] The polymer with end groups of formula (I) particularly preferably has a mean molecular weight M nfrom 2,000 to 20,000 g / mol, preferably 2,500 to 15,000 g / mol, and an average aldimine functionality of 1.8 to 3, preferably 2 to 3.

[0034] Preferably, the polymer with end groups of formula (I) has a polyether or polyester backbone.

[0035] The polymer with end groups of formula (I) particularly preferably has a polyether backbone.

[0036] In particular, the polyether backbone 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 backbone may contain up to 25 wt% oxy-1,2-ethylene units based on the total polyether backbone.

[0037] A poly(oxy-1,2-propylene) backbone is most preferred, which may contain up to 25 wt%, preferably up to 20 wt%, oxy-1,2-ethylene units based on the entire polyether backbone, particularly at the chain ends.

[0038] A polymer with end groups of formula (I) having a polyether backbone preferably has a medium molecular weight M n from 4,000 to 15,000 g / mol.

[0039] The polymer contains end groups of formula (I),

[0040] O

[0041] L (i)

[0042] — NX — A

[0043] H

[0044] where

[0045] X for O, S or NR 1 and R 1 stands for H or a monovalent hydrocarbon residue with 1 to 18 C atoms, and

[0046] A stands for a monovalent organic residue with 7 to 30 carbon atoms containing an aromatic aldimine group.

[0047] R is preferred1 for methyl, ethyl, cyclohexyl or benzyl.

[0048] Preferably, X represents O. Such an end group of formula (I) is bonded to the polymer via a urethane group. Such a polymer is particularly easy to access and allows for particularly high extensibility.

[0049] In the end groups of formula (I), A preferentially represents a remainder of formula ---G 1 -N=CH-Z or --"G 2 -CH=NR 3 , wo at

[0050] G 1 for a divalent aliphatic, cycloaliphatic or arylaliphatic hydrocarbon residue, optionally containing ether oxygen, with 2 to 18 C atoms,Z stands for an aromatic or heteroaromatic five- or six-membered ring, optionally substituted and / or fused, comprising a total of 4 to 25 C atoms,

[0051] G 2stands for a divalent, possibly oxygen-containing, arylaliphatic hydrocarbon residue with 5 to 12 C atoms, which is bonded to X via an aliphatic C atom and to CH=N via an aromatic or heteroaromatic ring, and

[0052] R 3 stands for a monovalent, possibly ether-oxygen-containing aliphatic, cycloaliphatic or arylaliphatic hydrocarbon residue with 1 to 13 C atoms.

[0053] Preferably, the end groups of formula (I) represent end groups of formula (1a) or end groups of formula (Ib),

[0054]

[0055] where X, G 1 , Z, G 2 and R 3 which have the meanings already mentioned.

[0056] Preferably, Z represents a phenyl group, a naphthyl group, a furyl group, a pyridine group, a pyrrole group, an indole group or a thiophene group, in particular a phenyl group, a naphthyl group or a furyl group, wherein these groups are optionally substituted, in particular with alkyl or alkoxy or nitro or ester groups.

[0057] 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, 2,5-Dimethylphenyl, 2-Methoxyphenyl, 3-Me-thoxyphenyl, 4-Methoxyphenyl, 2-Ethoxyphenyl, 3-Ethoxyphenyl, 4-Ethoxyphenyl, 4-Propoxyphenyl, 4-lsopropoxyphenyl, 4-Butoxyphenyl, 4-Pentoxyphenyl, 4-Decyl-oxyphenyl, 4-Dodecyloxyphenyl, 2,3-Dimethoxyphenyl, 2,4-Dimethoxyphenyl, 2,5-Dimethoxyphenyl, 3,4-Dimethoxyphenyl, 3,5-Dimethoxyphenyl, 2,4,6-Trimethyl-phenyl, 2,4,5-Trimethoxyphenyl, 2,4,6-Trimethoxyphenyl, 3,4,5-Trimethoxyphenyl, 4-Methoxycarbonylphenyl, 4-Ethoxycarbonylphenyl, 3-Nitrophenyl, 1 -Naphthyl, 2-Naphthyl, 2-Furyl und 5-Methyl-2-furyl.

[0058] Davon bevorzugt ist Phenyl, 4-Methoxycarbonylphenyl, 4-Ethoxycarbonylphenyl, 3-Nitrophenyl, 2-Furyl oder 5-Methyl-2-furyl.

[0059] Z is particularly favored as a phenyl group. Such end groups of formula (I) are derived from benzaldehyde. They are particularly readily available both technically and commercially and allow for rapid curing.

[0060] Furthermore, Z is particularly preferred for 2-furyl or 5-methyl-2-furyl. Such aldimine groups enable particularly rapid curing.

[0061] Aldimines derived from benzaldehyde or other volatile aldehydes typically cause a strong, unpleasant odor in curable polyurethane compositions, which is clearly perceptible during and after application and severely limits their use. However, in the curable composition according to the invention, no aldehyde odor is produced, 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.

[0062] G is preferred 1 for a divalent aliphatic hydrocarbon residue, possibly containing ether oxygen, with 4 to 12 C atoms.

[0063] In particular, G 1 selected from the group consisting of 1,2-ethylene, 1,2-propylene, 1,3-propylene, 1,4-butylene, 1,5-pentylene, 1,6-hexylene, 1,8-octylene, 1,10-decylene, 1,12-dodecylene, (1,5,5-trimethylcyclohexan-1-yl)methane-1,3-,3-oxa-1,5-pentylene and 3,6-dioxa-1,8-octylene.

[0064] G is particularly favored 1 for 3-oxa-1,5-pentylene. G is preferred. 2 for the remainder of the formula

[0065]

[0066]

[0067] Especially preferred is

[0068]

[0069] R is preferred 3for a residue selected from the list consisting of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert. Butyl, 2-Butyl, Pentyl, 2-Pentyl, 3-Methylbutyl, 3-Methyl-2-butyl, Hexyl, Octyl, 2-Ethylhexyl, Nonyl, Decyl, Tridecyl, 2-Methoxyethyl, 2-Ethoxyethyl, 3-Methoxypropyl, 3-Ethoxypropyl, Cyclohexyl, Benzyl or 2-Phenylethyl.

[0070] Of these, butyl, hexyl, octyl, 2-ethylhexyl, 2-methoxyethyl, 2-ethoxy-ethyl, 3-methoxypropyl, 3-ethoxypropyl or benzyl are preferred.

[0071] Butyl or benzyl are particularly preferred.

[0072] Preferably, the polymer with end groups of formula (I) is obtained by reacting an isocyanate-containing polymer with an aldimine of formula HX— A j n a ratio of the number of moles of isocyanate groups to the number of moles of aldimine of formula HX—A of at least 1 , where A and X have the meanings already mentioned.

[0073] Particularly preferred is the polymer with end groups of formula (I) obtained by reacting an isocyanate-containing polymer with an aldimine of formula (Illa) or formula (Illb) in a ratio of the number of moles of isocyanate groups to the number of moles of aldimine of formula (Illa) or (Illb) of at least 1 ,

[0074] HX— G 1 -N=CH— Z ( llla )

[0075] HX— G 2 -CH=N— R 3 (Hlb)

[0076] where X, G 1 , G 2 , Z and R 3the meanings already mentioned. In a preferred embodiment of the invention, the end groups of formula (I) are end groups of formula (Ia). Such a polymer is obtained in particular by reacting an isocyanate-containing polymer with an aldimine of formula (Illa) in a ratio of the number of moles of isocyanate groups to the number of moles of aldimine of formula (Illa) of at least 1, in particular in a ratio of 1.0 to 1.2, preferably 1.0 to 1.1.

[0077] A suitable aldimine of formula (Illa) is preferably obtained by reacting an amine of formula HX—G 1 — NH2 with an aldehyde of the formula O— CH— Z with the release of water, in particular in a stoichiometric ratio of about 1 / 1. Preferably the amine and the aldehyde are mixed and the released water is removed by vacuum distillation.

[0078] As an amine of the formula HX— G 1— Particularly suitable for NH2 conversion are N-methyl-1,2-ethanediamine, N-methyl-1,2-propanediamine, N-methyl-1,3-propanediamine, N-methyl-1,4-butanediamine, N-methyl-1,5-pentanediamine, N-methyl-1,6-hexanediamine, N-methyl-1,8-octanediamine, N-methyl-1,10-decanediamine, N-methyl-1,12-dodecanediamine, the aforementioned amines with ethyl, cyclohexyl, or benzyl instead of methyl on the nitrogen atom, as well as 5-aminopentanol, 6-aminohexanol, 8-aminooctanol, 10-aminodecanol, 12-aminododecanol, 3-aminomethyl-3,5,5-trimethylcyclohexanol, 2-(2-aminoethoxy)ethanol, or 2-(2-(2-Aminoethoxy)ethoxy)ethanol, as well as addition products of primary diamines to maleic acid diesters in a molar ratio of 1:1, such as in particular the addition product of isophorone diamine to dimethyl maleate or diethyl maleate in a molar ratio of 1:1.

[0079] Especially preferred as the amine of the formula HX— G 1 — NH2j st 2-(2-Aminoethoxy)ethanol.

[0080] Als Aldehyd der Formel O=CH— Z geeignet ist insbesondere Benzaldehyd, 2-Methylbenzaldehyd, 3-Methylbenzaldehyd, 4-Methylbenzaldehyd, 4-Ethylbenz-aldehyd, 4-lsopropylbenzaldehyd, 4-tert-Butylbenzaldehyd, 4-C -i4-Alkylbenz-aldehyd, 2,5-Dimethylbenzaldehyd, 2-Methoxybenzaldehyd, 3-Methoxybenz-aldehyd, 4-Methoxybenzaldehyd, 2-Ethoxybenzaldehyd, 3-Ethoxybenzaldehyd, 4-Ethoxybenzaldehyd, 4-Propoxybenzaldehyd, 4-lsopropoxybenzaldehyd, 4-Butoxy-benzaldehyd, 4-Pentoxybenzaldehyd, 4-Decyloxybenzaldehyd, 4-Dodecyloxy-benzaldehyd, 2,3-Dimethoxybenzaldehyd, 2,4-Dimethoxybenzaldehyd, 2,5-Di-methoxybenzaldehyd, 3,4-Dimethoxybenzaldehyd, 3,5-Dimethoxybenzaldehyd, 2,4,6-Trimethylbenzaldehyd, 2,4,5-Trimethoxybenzaldehyd, 2,4,6-Trimethoxy-benzaldehyd, 3,4,5-Trimethoxybenzaldehyd, 4-Formylbenzoesäureester, insbesondere 4-Formylbenzoesäuremethylester oder 4-Formylbenzoesäureethylester, 3-Nitrobenzaldehyd, 1-Naphthaldehyd, 2-Naphthaldehyd, Furfural oder 5-Methyl-furfural.

[0081] Preferred are benzaldehyde, 4-formylbenzoic acid methyl ester, 4-formylbenzoic acid ethyl ester, 3-nitrobenzaldehyde, 2-methylbenzaldehyde, 3-methylbenzaldehyde, 4-methylbenzaldehyde, 4-methoxybenzaldehyde, 3,4-dimethoxybenzaldehyde, furfural or 5-methylfurfural, in particular benzaldehyde, 4-formylbenzoic acid methyl ester, 3-nitrobenzaldehyde, furfural or 5-methylfurfural.

[0082] The aldimine of formula (Illa) is specifically selected from the list consisting of N-benzylidene-5-aminopentanol, N-benzylidene-6-aminohexanol, N-benzylidene-8-aminooctanol, N-benzylidene-10-aminodecanol, N-benzylidene-12-aminododecanol, N-benzylidene-3-aminomethyl-3,5,5-trimethylcyclohexanol, N-benzylidene-2-(2-aminoethoxy)ethanol, N-benzylidene-2-(2-(2-aminoethoxy)ethoxy)ethanol and corresponding compounds derived from 4-formylbenzoic acid methyl ester, 4-formylbenzoic acid ethyl ester, 3-nitrobenzaldehyde, furfural and 5-methylfurfural instead of benzaldehyde.

[0083] Particularly suitable are N-benzylidene-2-(2-aminoethoxy)ethanol, N-(4-methoxycarbonyl)benzylidene-2-(2-aminoethoxy)ethanol, N-(4-ethoxycarbonyl)benzylidene-2-(2-aminoethoxy)ethanol, N-(3-nitro)benzylidene-2-(2-aminoethoxy)ethanol, N-furfurylidene-2-(2-aminoethoxy)ethanol, or N-(5-methylfurfurylidene)-2-(2-aminoethoxy)ethanol. In a further preferred embodiment of the invention, the end groups of formula (I) are end groups of formula (Ib). Such a polymer is obtained in particular by reacting an isocyanate-containing polymer with an aldimine of formula (11b) in a ratio of the number of moles of isocyanate groups to the number of moles of aldimine of formula (11b) of at least 1, in particular from 1.0 to 1.2, preferably from 1.0 to 1.1.

[0084] An aldimine of formula (111b) is in turn obtained by reacting an aldehyde of formula (IV) with an amine of formula R 3-NH2 with the release of water, particularly in a stoichiometric ratio of about 1 / 1. Preferably, the amine and the aldehyde are mixed and the released water is removed by vacuum distillation.

[0085] HX-G 2 -CH=O (IV)

[0086] Suitable as an aldehyde of formula (IV) is in particular 5-hydroxymethylfurfural or ethoxylated salicylaldehyde, in particular 2-(2-hydroxyethoxy)benzaldehyde and / or 2-(2-(2-hydroxyethoxy)ethoxy)benzaldehyde.

[0087] Suitable aldimine of formula (111b) is in particular N-(5-hydroxymethylfurfurylidene)butanamine, N-(5-hydroxymethylfurfurylidene)benzylamine, N-(2-(2-hydroxyethoxy)benzylidene)butanamine and / or N-(2-(2-(2-hydroxyethoxy)ethoxy)benzylidene)butanamine, N-(2-(2-hydroxyethoxy)benzylidene)benzylamine and / or N-(2-(2-(2-hydroxyethoxy)ethoxy)benzylidene)benzylamine, as well as corresponding compounds with further of the aforementioned R groups. 3instead of butyl or benzyl.

[0088] Instead of using an aldimine of formula (111b), the reaction of the isocyanate-containing polymer can also be carried out first with the aldehyde of formula (IV) in a ratio of the number of moles of isocyanate groups to the number of moles of aldehyde of formula (IV) of at least 1, in particular in a ratio of 1.0 to 1.2, preferably 1.0 to 1.1, followed by the reaction of the resulting aldehyde-functional polymer with an amine of formula R. 3 -NH2 with the release of water, especially in a ratio of the number of moles of aldehyde groups to the number of moles of amine of formula R 3 -NH2 of about 1.

[0089] The reaction of the isocyanate-containing polymer with the aldimine of formula (11) or (111b) preferably takes place at a temperature of 20 to 140 °C until all isocyanate groups have reacted, optionally with the use of a suitable catalyst. In the case of X = O, the reaction preferably takes place at a temperature of 40 to 140 °C, particularly 60 to 120 °C, optionally in the presence of a suitable catalyst.

[0090] A polymer containing isocyanate groups is particularly suitable as a reaction product of at least one monomeric diisocyanate with at least one polymeric polyol in an NCO / OH ratio of at least 1.5 / 1, preferably at least 1.8 / 1.

[0091] Particularly preferred is a reaction product of at least one monomeric diisocyanate with at least one polymeric polyol in an NCO / OH ratio of 3 / 1 to 10 / 1, preferably 4 / 1 to 9 / 1, particularly 5 / 1 to 8 / 1, and subsequent removal of the monomeric diisocyanate by means of a suitable separation process down to a content of less than 0.5 wt%, preferably less than 0.2 wt%, particularly less than 0.1 wt%, based on the polymer.

[0092] Suitable monomeric diisocyanates include, in particular, 1,5-pentane diisocyanate (PDI), 1,6-hexane diisocyanate (HDI), 2,2(4),4-trimethyl-1,6-hexane diisocyanate (TMDI), 1-methyl-2,4(6)-diisocyanatocyclohexane (HeTDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H12MDI), 4(2),4'-diphenylmethane diisocyanate (MDI), or 2,4(6)-toluene diisocyanate (TDI). HDI or IPDI are preferred, and IPDI is particularly preferred.

[0093] Polymeric polyols suitable for polymeric use include polymers with an OH number of 9 to 114 mg KOH / g, preferably 12 to 57 mg KOH / g, and particularly 18 to 45 mg KOH / g. Polyether polyols or polyester polyols are particularly suitable for polymeric use.

[0094] Polyether polyols, also called poly(oxyalkylene) polyols, are particularly preferred.

[0095] Preferred polyether polyols are polymerization products of ethylene oxide or 1,2-propylene oxide or 1,2- or 2,3-butylene oxide or oxetane or tetrahydrofuran, or mixtures thereof, wherein these may be polymerized using a starter molecule having two or more active hydrogen atoms, in particular a starter molecule such as water, ammonia or a compound with several OH or NH groups such as, for example, 1,2-ethanediol, 1,2- or 1,3-propanediol, neopentyl glycol, diethylene glycol, triethylene glycol, the isomeric dipropylene glycols or tripropylene glycols, the isomeric butanediols, pentanediols, hexanediols, heptanediols, octanediols, nonanediols, decanediols, undecanediols, 1,3- or 1,4-cyclohexanedimethanol, bisphenol A, hydrogenated bisphenol A, 1,1,1-Trimethylolethane, 1,1,1-Trimethylolpropane, glycerol or aniline, or mixtures of the aforementioned compounds.

[0096] Particularly preferred are poly(oxy-1,2-propylene)diols, poly(oxy-1,2-propylene)triols, or so-called ethylene oxide-terminated (EO-endcapped or EO-tipped) poly(oxy-1,2-propylene)diols or triols. The latter are polyoxyethylene-polyoxy-propylene mixed polyols, which are obtained in particular by further alkoxylating polyoxypropylene diols or triols after completion of the propoxylation reaction with ethylene oxide, thereby ultimately exhibiting primary hydroxyl groups.

[0097] Poly(oxy-1,3-propylene)diols or poly(oxy-1,4-butylene)diols are particularly preferred.

[0098] Polyols with a degree of unsaturation of less than 0.02 meq / g, in particular less than 0.01 meq / g, are preferred.

[0099] Particularly preferred is the isocyanate group-containing polymer a reaction product of an ethylene oxide-terminated poly(oxy-1,2-propylene)triol with an OH number of 28 to 34 mg KOH / g and IPDI in an NCO / OH ratio of 3 / 1 to 10 / 1 and subsequent removal of monomeric IPDI.

[0100] The isocyanate group-containing polymer preferably has a medium NCO functionality of 1.8 to 3, preferably 2 to 3.

[0101] The isocyanate-containing polymer preferably has a medium molecular weight M n from 1,200 to 20,000 g / mol, preferably 2,200 to 15,000 g / mol, in particular 4,000 to 10,000 g / mol.

[0102] The isocyanate group-containing polymer preferably has an NCO content based on the isocyanate group-containing polymer of 0.6 to 6 wt%, preferably 0.9 to 3.5 wt%, in particular 1.3 to 2.7 wt%.

[0103] The NCO content is determined in particular by reacting the isocyanate groups with an excess of dibutylamine and back-titrating the unreacted dibutylamine with aqueous hydrochloric acid.

[0104] Preferably, the isocyanate-containing polymer has a monomeric diisocyanate content of less than 0.5 wt%, preferably less than 0.2 wt%, and particularly less than 0.1 wt%, based on the isocyanate-containing polymer. Such a polymer is typically particularly low-viscosity.

[0105] The hardenable composition further comprises at least one compound with two or more 1,3-keto ester groups of formula (II),

[0106]

[0107] where R 2 stands for a monovalent hydrocarbon residue with 1 to 6 carbon atoms.

[0108] Preferably, the compound has two or more 1,3-ketoester groups of formula (II) and is liquid at room temperature. In particular, it has a viscosity at 20 °C of 0.1 to 50 Pa s, more preferably 0.1 to 30 Pa s, and more preferably 0.1 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-plate distance of 0.05 mm, and a shear rate of 10 s⁻¹. -1 . Such a compound enables compositions that can be processed well at ambient temperature without the addition of solvents or thinners.

[0109] Preferably, the compound with two or more 1,3-keto ester groups of formula (II) has two to six, particularly preferably two to four, in particular two to three, 1,3-keto ester groups of formula (II).

[0110] In the case of an oligomeric or polymeric mixture of compounds with two or more 1,3-keto ester groups of formula (II), the average functionality with respect to the 1,3-keto ester groups of formula (II) is preferably in the range of 1.5 to 4, particularly preferably 1.8 to 3, and especially 2 to 3.

[0111] Preferably, the compound with two or more 1,3-keto ester groups of formula (II) has a molecular weight or, in the case of an oligomeric or polymeric mixture of compounds with two or more 1,3-keto ester groups of formula (II), an average molecular weight M n from 230 to 10,000 g / mol, particularly preferably 250 to 6,000 g / mol, especially 500 to 3,000 g / mol.

[0112] R is preferred 2 in formula (II) for an alkyl group having 1 to 6 carbon atoms or for phenyl, particularly preferably for methyl, ethyl, propyl, isopropyl, butyl or phenyl.

[0113] R is the most preferred choice. 2In formula (II), the methyl group and the ketoester groups of formula (II) are therefore acetoacetate groups. Compounds with acetoacetate groups are particularly easy to access and allow for compositions with especially rapid curing.

[0114] The compound with two or more 1,3-keto ester groups of formula (II) is preferably obtained from the transesterification of at least one compound with two or more hydroxyl groups and at least one 1,3-keto ester of formula (V),

[0115]

[0116] where R stands for C1-6 alkyl and R 2 which has the meanings already mentioned. Preferably, R stands for methyl, ethyl or tert-butyl I, particularly preferably for ethyl or tert-butyl I, and especially for ethyl.

[0117] The transesterification is preferably carried out at a temperature in the range of 50 to 150 °C with distillative removal of the released alcohol ROH and optionally fragmentation products thereof, optionally under vacuum and optionally in the presence of a suitable catalyst.

[0118] It is also possible to produce the compound by reacting it with two or more hydroxyl groups with diketene or the diketene adduct with acetone (= 2,2,6-trimethyl-4H-1,3-dioxin-4-one), whereby acetone is released in the case of the acetone-diketene adduct.

[0119] Suitable compounds with two or more hydroxyl groups include commercially available OH-functional compounds or polymers, 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, 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, glycerin, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, pentaerythritol, ethoxylated or especially propoxylated glycerin, ethoxylated or especially propoxylated 1,1,1-trimethylolpropane, poly(oxy-1,2-propylene)diols, EO-terminated poly(oxy-1,2-propylene)diols, poly(oxy-1,2-propylene)triols, EO-terminated poly(oxy-1,2-propylene)triols, di- or trimer fatty acid-based polyester polyols, castor oil, derivatives of castor oil or hydroxylated vegetable oils.Preferably, the compound is one with two or more 1,3-keto ester groups of formula (II) selected from the group 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, glyceryl diacetoacetate, glyceryl triacetoacetate, 1 ,1 ,1 -Trimethylolethanediacetoacetate, 1,1,1 -Trimethylolethanetriacetoacetate, 1,1,1 -Trimethylolpropanediacetoacetate, 1,1,1-Trimethylolpropanetriacetoacetate, the triacetoacetate of propoxylated 1,1,1-Trimethylolpropane with an overall average molecular weight M. n from 500 to 2,000 g / mol, poly(oxy-1,2-propylene)diol diacetoacetate with medium molecular weight M nfrom 600 to 5,000 g / mol, poly(oxy-1,2-propylene)trioltriacetoacetate with medium molecular weight M n poly(oxy-1,2-propylene)triol triacetoacetate containing ethylene oxide units, with a medium molecular weight M, ranging from 2,000 to 6,000 g / mol n from 2,000 to 6,000 g / mol, dimer fatty acid-based polyesterdiol diacetoacetate with medium molecular weight M n from 1,000 to 2,500 g / mol, trimer fatty acid-based polyestertrioltriacetoacetate with medium molecular weight M n from 1,000 to 3,000 g / mol, castor oil diacetoacetate and castor oil triacetoacetate.

[0120] Preferred among these is 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-1,1,3-hexanediol diacetoacetate, 1,1,1-trimethylolpropane diacetoacetate, 1,1,1-trimethylolpropane triacetoacetate, a triacetoacetate of propoxylated 1,1,1-trimethylolpropane with an overall average molecular weight M n from 500 to 2,000 g / mol, preferably 500 to 600 g / mol, dimer fatty acid-based polyesterdiol diacetoacetate with medium molecular weight M n from 1,000 to 2,500 g / mol or trimer fatty acid-based polyestertrioltriacetoacetate with medium molecular weight M n from 1,000 to 3,000 g / mol.

[0121] A triacetoacetate of propoxylated 1,1,1-trimethylol-propane with an overall average molecular weight M is particularly preferred. nfrom 500 to 600 g / mol, 2-Methyl-1,3-propanediol diacetoacetate, neopentyl glycol diacetoacetate, 1,6-hexanediol diacetoacetate, 3-Methyl-1,5-pentanediol diacetoacetate, 2-Ethyl-1,3-hexanediol diacetoacetate or a dimer fatty acid-based polyester diacetoacetate with medium molecular weight M n from 1,000 to 2,500 g / mol.

[0122] A triacetoacetate of propoxylated 1,1,1-trimethylolpropane with an overall average molecular weight M is particularly preferred. n from 500 to 600 g / mol.

[0123] Preferably, the ratio of the number of 1,3-ketoester groups of formula (II) to the number of end groups of formula (I) in the curable composition is 1 to 4, particularly preferably 1.5 to 3.5, and especially 2 to 3. Such a composition cures quickly and without defects to a cured polymer with high strength and ductility.

[0124] Preferably, the ratio of the number of 1,3-keto ester groups of formula (II) to the number of aldimine groups in the hardenable composition is 1 to 4, particularly preferably 1.5 to 3.5, especially 2 to 3.

[0125] The hardenable composition may also contain additional components, in particular

[0126] - Fillers, in particular ground or precipitated calcium carbonates, which may be coated with fatty acids, especially stearates, barites (barytes), quartz flours, quartz sands, dolomites, wollastonites, kaolins, calcined kaolins, layered silicates such as mica or talc, zeolites, aluminum hydroxides, magnesium hydroxides, silicas including highly dispersed silicas from pyrolysis processes, industrially produced carbon black, graphite, ground fillers from agricultural sources such as, in particular, olive kernel flour or nutshell flour, metal powders, for example of aluminum, copper, iron, silver or steel, PVC powder or hollow spheres,

[0127] - Fibers, in particular glass fibers, carbon fibers, metal fibers, ceramic fibers, hemp fibers, cellulose fibers or plastic fibers such as polyamide fibers, polyethylene fibers or polypropylene fibers, - Nanofillers or nanofibers such as graphene or carbon nanotubes,

[0128] - Dyes,

[0129] - Pigments, especially titanium dioxide, chromium oxide, iron oxides or organic pigments,

[0130] - Plasticizers, in particular phthalates, especially 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 diisononyl-1,4-cyclohexanedicarboxylate, isophthalates, trimellitates, adipates, in particular dioctyl adipate (DOA), azelates, sebacates, citrates, benzoates, glycol ethers, glycol esters, plasticizers with a polyether structure, in particular poly(oxy-1,2-propylene) monols, diols or triols, optionally with blocked Hydroxyl groups, especially in the form of acetyl groups, as well as organic sulfonates or phosphates, especially diphenylcresyl phosphate (DPK) or tris-2-ethylhexyl phosphate (TOF), polybutenes, polyisobutenes or plasticizers derived from natural fats or oils,in particular epoxidized soybean or linseed oil or rapeseed oil methyl ester, wherein phthalates, hydrogenated phthalates, adipates or plasticizers with a polyether structure are preferred,

[0131] - Solvents,

[0132] - other aldimines, in particular low molecular weight mono- or polyaldimines, - other 1,3-keto esters, in particular monofunctional 1,3-keto esters,

[0133] - Catalysts for the reaction of 1,3-ketoester groups with aldimine groups, - Modifying agents such as hydrocarbon resins, natural or synthetic waxes or bitumen,

[0134] - Rheology modifiers, in particular urea compounds, layered silicates such as bentonites, castor oil derivatives, hydrogenated castor oil, polyamides, polyurethanes, pyrogenic silicas or hydrophobically modified polyoxyethylenes, - Drying agents, in particular molecular sieves, calcium oxide, mono-oxazolidines such as Incozol® 2 (from Incorez), orthoesters or alkoxysilanes, - 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,

[0135] - 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 polyethylene (PE), polypropylene (PP), polyisobutylene, ethylene vinyl acetate copolymers (EVA) and atactic poly-α-olefins (APAO), - flame-retardant substances, in particular the fillers already mentioned: aluminum hydroxide or magnesium hydroxide, organophosphates, ammonium polyphosphates, expanding graphite, melamine compounds, boron compounds or antimony compounds,

[0136] - Additives, in particular wetting agents, leveling agents, defoamers, deaerators, stabilizers against oxidation, heat, light or UV radiation or biocides, as well as other substances commonly used in curable compositions.

[0137] Preferably, the curable composition contains at least one further component selected from fillers, pigments, plasticizers and adhesion promoters.

[0138] The curable composition preferably contains less than 10 wt%, more preferably less than 5 wt%, and particularly less than 1 wt%, volatile organic solvents with a boiling point at normal pressure of less than 250 °C, relative to the total composition. Such a composition causes particularly low emissions.

[0139] The curable composition is preferably non-water-based, meaning it is neither a solution, emulsion, nor dispersion in water. It is preferably largely free of water or contains only a small amount. Such a composition cures rapidly regardless of ambient humidity, can be used in thick layers and / or between waterproof substrates, and exhibits minimal shrinkage during curing. The curable composition preferably contains less than 10% by weight, more preferably less than 5% by weight, and particularly less than 2% by weight, water based on the total composition.

[0140] In particular, the curable composition contains less than 10 wt%, preferably less than 5 wt%, particularly less than 1 wt%, volatile organic solvents with a boiling point at normal pressure of less than 250 °C and less than 10 wt%, preferably less than 5 wt%, particularly less than 2 wt%, water based on the total composition.

[0141] The curable composition is preferably free of isocyanate groups.

[0142] In a preferred embodiment of the invention, the curable composition contains at least one plasticizer, at least one filler, additionally either carbon black or titanium dioxide, and optionally at least one adhesion promoter. Such a composition is particularly suitable as an elastic adhesive or sealant with good resistance to weathering and UV light. If titanium dioxide is included, a small amount of carbon black may also be present, so that the cured composition has a gray hue.

[0143] Preferably, the curable composition is used as a two-component composition comprising two separately packaged components. The polymers with end groups of formula (I) are part of the first component, and the compounds with two or more 1,3-ketoester groups of formula (II) are part of the second component.

[0144] Further ingredients of the composition may be present as components of the first and / or the second component, wherein reactive components with end groups of formula (I) are preferably present as components of the second component, and reactive components with 1,3-keto ester groups of formula (II) are preferably present as components of the first component. Each of the two components is stable on its own in suitable packaging. For use, the components are mixed together shortly before or during application, at which point the curing process begins.

[0145] The first and second components of the curable composition are produced separately. The ingredients of each component are then mixed together to create a macroscopically homogeneous mass.

[0146] The first and second components are preferably formulated to have a consistency that allows them to be easily mixed together under ambient conditions using simple methods, i.e., as quickly and completely as possible. Preferably, the two components are liquid or pasty and have a similar viscosity.

[0147] The first and second components are each stored in separate containers. Suitable containers include, in particular, drums, containers, pails, buckets, canisters, cans, bags, foil packs, cartridges, or tubes.

[0148] To use the curable composition, the components are mixed together shortly before or during application. The mixing ratio is preferably chosen such that the ratio of the number of 1,3-ketoester groups of formula (II) to the number of end groups of formula (I) is within the preferred range. In parts by weight, the mixing ratio between the first and second components is typically about 100:1 to 1:1, particularly 50:1 to 1:1.

[0149] If the components are mixed before application, care must be taken to ensure that not too much time elapses between mixing and application, as otherwise the onset of the reaction and the associated increase in viscosity can lead to problems such as insufficient applicability or slowed or incomplete adhesion to the substrate. In particular, the open time of the composition should not be exceeded during application.

[0150] The term "open time" refers to the period between the mixing of the components and the end of a state of the composition suitable for processing.

[0151] Mixing preferably takes place at ambient temperature, preferably at a temperature in the range of -5 to 50 °C, preferably 0 to 40 °C, particularly 5 to 35 °C.

[0152] Upon mixing the ingredients or components, the composition begins to harden due to the onset of a chemical reaction. In particular, any 1,3-keto ester groups present, such as those of formula (II), react with the end groups of formula (I). It can be assumed that typically two keto ester groups react with an end group of formula (I) to form a cyclic structural unit, releasing water. No aldehyde is released in this process.

[0153] The 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.

[0154] Another object of the invention is the hardened composition obtained from the hardenable composition after mixing the ingredients or components.

[0155] Preferably, the cured composition has a tensile strength of at least 4 MPa, determined according to DIN EN 53504 at a tensile speed of 200 mm / min on dumbbell-shaped test specimens with a thickness of 2 mm and a length of 75 mm, with a web length of 30 mm and a web width of 4 mm.

[0156] Preferably, the hardened composition has an elongation at break of at least 200%, in particular at least 300%, determined according to DIN EN 53504 at a tensile speed of 200 mm / min on dumbbell-shaped test specimens with a thickness of 2 mm and a length of 75 mm, with a web length of 30 mm and a web width of 4 mm.

[0157] Preferably, the cured composition has a tear resistance of at least 4.5 N / mm, in particular at least 5 N / mm, determined according to DIN ISO 34-1 method B (angled test specimen) at a specimen thickness of 2 mm and a tensile speed of 500 mm / min.

[0158] Preferably the tensile strength of the cured composition is at least 4 MPa and / or the elongation at break is at least 200%, preferably at least 300%, determined according to DIN EN 53504 at a tensile speed of 200 mm / min on dumbbell-shaped test specimens with a thickness of 2 mm and a length of 75 mm, with a web length of 30 mm and a web width of 4 mm.

[0159] The curable composition is suitable for a wide variety of applications. It is particularly suitable for applications requiring elastic properties with high elongation.

[0160] Another 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 of the composition are mixed together and the mixed composition is applied in liquid form to at least one substrate.

[0161] Due to its high elasticity, it is particularly preferred for use as an elastic adhesive or elastic sealant.

[0162] Suitable substrates include in particular:

[0163] - Glass, glass ceramics, concrete, mortar, cement screed, fiber cement, brick, tile, gypsum or natural stones such as granite or marble;

[0164] - Repair or leveling compounds based on PCC (polymer-modified cement mortar) or ECC (epoxy-modified cement mortar); - Metals or alloys such as aluminium, iron, steel, copper, other non-ferrous metals, including surface-treated metals or alloys such as galvanized or chrome-plated metals;

[0165] - Asphalt or bitumen;

[0166] - Leather, textiles, paper, wood, with resins, for example phenolic, melamine or epoxy resins, bonded wood materials, resin-textile composites or other so-called polymer composites;

[0167] - Plastics such as rigid and flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resins, phenolic resins, PUR, POM, TPO, PE, PP, EPM or EPDM, either untreated or surface-treated, for example by means of plasma, corona or flames;

[0168] - fiber-reinforced plastics, such as carbon fiber reinforced plastics (CFRP), glass fiber reinforced plastics (GFRP), natural fiber reinforced plastics (NFRP) and sheet moulding compounds (SMC);

[0169] - Insulating materials, in particular foams, especially made of EPS, XPS, PUR, PIR, aerogel or foamed glass (Foamglas), or fibers made of rock wool or glass wool,

[0170] - coated or painted substrates, in particular painted tiles, painted concrete, powder-coated metals or alloys or painted sheets;

[0171] - Coatings, paints or varnishes.

[0172] The substrates can be pretreated before application if necessary, in particular by physical and / or chemical cleaning processes or by applying an activator or a primer.

[0173] Two identical or two different substrates can be bonded and / or sealed.

[0174] An article is obtained from the use of the curable composition. The article is, in particular, bonded, sealed, or coated with the curable composition. This article may be a structure or part thereof, in particular a building structure, bridge, roof, stairwell, or facade; or it may be an industrial good or a consumer good, in particular a window, pipe, wind turbine rotor blade, household appliance, or means of transport such as, in particular, an automobile, bus, truck, rail vehicle, ship, aircraft, or helicopter, or an attachment thereof.

[0175] Examples

[0176] The following are exemplary embodiments intended to further illustrate the described invention. Of course, the invention is not limited to these described embodiments.

[0177] A temperature of 23+1 °C and a relative humidity of 50+5% is referred to as "standard climate" ("NC").

[0178] Unless otherwise stated, the chemicals used were from Merck.

[0179] The viscosity was measured on a thermostatically controlled 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.

[0180] Infrared spectra (FT-IR) were measured as undiluted films on a Thermo Scientific Nicolet iS5 FT-IR instrument equipped with a horizontal ATR measuring unit with a diamond crystal.

[0181] The content of monomeric diisocyanate was determined for all isocyanate group-containing polymers by HPLC (detection via photodiode array; 0.04 M sodium acetate / acetonitrile as mobile phase) after prior derivation using N-propyl-4-nitrobencylamine.

[0182] Production of OH-functional aldimines:

[0183] Aldimine-1: N-benzylidene-2-(2-aminoethoxy)ethanol

[0184] 105.0 g (1 mol) of 2-(2-aminoethoxy)ethanol (Diglycolamine® Agent, from Huntsman) was placed under a nitrogen atmosphere, mixed with 106.1 g (1 mol) of benzaldehyde with good stirring, and then the volatile components were removed at 80 °C and 10 mbar vacuum. 192.0 g of N-benzylidene-2-(2-aminoethoxy)ethanol was obtained as a clear, yellowish liquid.

[0185] Aldimin-2: N-(5-Methylfurfurylidene)-2-(2-aminoethoxy)ethanol. 52.5 g (0.5 mol) of 2-(2-Aminoethoxy)ethanol (Diglycolamine® Agent, from Huntsman) was placed under a nitrogen atmosphere, mixed with 55.1 g (0.5 mol) of 5-methylfurfural with good stirring, and then the volatile components were removed at 80 °C and 10 mbar vacuum. 98.1 g of N-(5-Methylfurfurylidene)-2-(2-aminoethoxy)ethanol was obtained as a clear, yellowish liquid.

[0186] Aldimin-3: Mixture of N-(2-(2-hydroxyethoxy)benzylidene)butanamine and N-(2-(2-(2-hydroxyethoxy)ethoxy)benzylidene)butanamine

[0187] 72.7 g (0.4 mol aldehyde groups) of a mixture of 2-(2-hydroxyethoxy)benzaldehyde and 2-(2-(2-hydroxyethoxy)ethoxy)benzaldehyde was placed under a nitrogen atmosphere and heated to 50 °C. Then, 29.9 g (0.4 mol) of butylamine were slowly added with good stirring, followed by stirring for 30 min at 60 °C, and then the volatile components were removed at 80 °C and 10 mbar vacuum. 95.2 g of a mixture of N-(2-(2-hydroxyethoxy)benzylidene)butane-1-am and N-(2-(2-(2-hydroxyethoxy)ethoxy)benzylidene)butane-1-amine were obtained as a clear, orange liquid with a calculated mean aldimine equivalent weight of 243.3 g / eq.

[0188] Production of isocyanate group-containing polymers:

[0189] Polymer NCO-1:

[0190] 780 g of ethylene oxide-terminated polyoxypropylenetriol (Desmophen® 5031 BT, OH number 28.0 mg KOH / g, OH functionality approx. 2.3, from Covestro) and 303 g of isophorone diisocyanate (Vestanat® IPDI, from Evonik) were reacted at 80 °C according to a known procedure to form a reaction mixture with an NCO content of 9.1 wt%. Subsequently, the volatile components, in particular unreacted isophorone diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 160 °C, pressure 0.1 to 0.005 mbar), yielding a polymer with an NCO content of 1.8 wt% and a monomeric isophorone diisocyanate content of 0.02 wt%.

[0191] Polymer NCO-2:

[0192] 818 g of polyoxypropylenediol (Acclaim® 4200, OH number 28.5 mg KOH / g, from Covestro) and 227 g of isophorone diisocyanate (Vestanat® IPDI, from Evonik) were reacted at 80°C according to a known procedure to form a reaction mixture with an NCO content of 6.6 wt%. Subsequently, the volatile components, in particular unreacted isophorone diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 160°C, pressure 0.1 to 0.005 mbar), yielding a polymer with an NCO content of 1.9 wt% and a monomeric isophorone diisocyanate content of 0.03 wt%.

[0193] Production of an aldehyde-functional polymer:

[0194] Polymer CHO-1:

[0195] 500 g of polymer NCO-1 (214 mmol NCO groups) was reacted with 27.7 g (220 mmol) of 5-hydroxymethylfurfural in the presence of 0.1 g of dibutyltin dilaurate under exclusion of moisture at 80 °C until no more isocyanate groups were detectable by IR spectroscopy. The resulting aldehyde-functional polymer had a viscosity of 64 Pa s at 20 °C and a calculated aldehyde equivalent weight of 2400 g / eq.

[0196] Production of aldimine-functional polymers:

[0197] Polymer A1:

[0198] 400 g of polymer NCO-1 (171 mmol NCO groups) was reacted with 34.6 g (179 mmol) of aldimine-1 in the presence of 0.1 g of dibutyltin dilaurate under exclusion of moisture at 80 °C until no more isocyanate groups were detectable by IR spectroscopy. The resulting aldimine-functional polymer had a viscosity of 143 Pa s at 20 °C and a calculated aldimine equivalent weight of 2428 g / eq.

[0199] Polymer A2:

[0200] 400 g of polymer NCO-1 (171 mmol NCO groups) was reacted with 35.3 g (179 mmol) of aldimine-2 in the presence of 0.1 g of dibutyltin dilaurate under exclusion of moisture at 80 °C until no more isocyanate groups were detectable by IR spectroscopy. The resulting aldimine-functional polymer had a viscosity of 194 Pa s at 20 °C and a calculated aldimine equivalent weight of 2432 g / eq. Polymer A3:

[0201] 400 g of polymer CHO-1 (167 mmol aldehyde groups) was mixed with 12.2 g (167 mmol) of butylamine, stirred for 30 min at 50 °C, and then the released water was removed under vacuum at 90 °C. The resulting aldimine-functional polymer had a viscosity of 120 Pa s at 20 °C and a calculated aldimine equivalent weight of 2416 g / eq.

[0202] Polymer A4:

[0203] 400 g of polymer NCO-1 (171 mmol NCO groups) was reacted with 43.5 g (179 mmol) of aldimine-3 in the presence of 0.1 g of dibutyltin dilaurate under exclusion of moisture at 80 °C until no more isocyanate groups were detectable by IR spectroscopy. The resulting aldimine-functional polymer had a viscosity of 127 Pa s at 20 °C and a calculated aldimine equivalent weight of 2478 g / eq.

[0204] Polymer A5:

[0205] 400 g of polymer NCO-2 (180 mmol NCO groups) was reacted with 35.5 g (184 mmol) of aldimine-1 in the presence of 0.1 g of dibutyltin dilaurate under exclusion of moisture at 80 °C until no more isocyanate groups were detectable by IR spectroscopy. The resulting aldimine-functional polymer had a viscosity of 111 Pa s at 20 °C and a calculated aldimine equivalent weight of 2367 g / eq.

[0206] Polymer R1:

[0207] 400 g (0.21 mol NH₂) of polyoxypropylenetriamine (Jeffamine® T-5000, from Huntsman) was placed under a nitrogen atmosphere, mixed with 22.3 g (0.21 mol) of benzaldehyde with thorough stirring, and then the volatile components were removed at 80 °C and 10 mbar vacuum. A clear, yellowish liquid with a calculated aldimine equivalent weight of 1993 g / eq was obtained.

[0208] Polymer R2:

[0209] 400 g (0.20 mol NH₂) of polyoxypropylenediamine (Jeffamine® D-4000, from Huntsman) was placed under a nitrogen atmosphere, mixed with 21.2 g (0.20 mol) of benzaldehyde with thorough stirring, and then the volatile components were removed at 80 °C and 10 mbar vacuum. A clear, yellowish liquid with a calculated aldimine equivalent weight of 2088 g / eq was obtained.

[0210] Polymers A1 to A5 contain end groups of formula (I) with X = 0. Polymers R1 and R2 contain end groups that do not correspond to formula (I) and serve as a comparison.

[0211] Production of compounds with keto ester groups:

[0212] Connection B1:

[0213] 50 g (0.49 mol OH) of a polyoxypropylenetriol (Desmophen® 4011 T, OH number 550 mg KOH / g, propoxylated 1,1,1-trimethylolpropane, from Covestro) was reacted with 67 g (0.52 mol) of ethyl acetoacetate and 0.1 g of tetra-n-butyl titanate (Tyzor® TnBT, from Dorf Ketal) and under vacuum, with removal of the volatile components, at a temperature of 80 to 140 °C. A clear, colorless liquid with a viscosity of 0.8 Pa s at 20 °C and a calculated acetoacetate equivalent weight of 186 g / eq was obtained.

[0214] Connection B2:

[0215] 104.1 g (2 mol OH) of neopentyl glycol (= 2,2-dimethyl-1,3-propanediol) was reacted with 286.3 g (2.2 mol) of ethyl acetoacetate and 0.4 g of tetra-n-butyl titanate under vacuum and after removal of the volatile components at a temperature of 80 to 140 °C. A clear, yellowish liquid with a viscosity at 20 °C of < 0.05 Pa s and a calculated acetoacetate equivalent weight of 136 g / eq was obtained.

[0216] Connection B3:

[0217] 500 g (1.1 mol OH) of amorphous dimer fatty acid-based polyester diol with an OH number of 123 mg KOH / g was reacted 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 under vacuum with removal of the volatile components at a temperature of 80 to 140 °C. 608.7 g of a clear, yellowish liquid with a viscosity at 20 °C of 14.4 Pa s and a calculated acetoacetate equivalent weight of 540 g / eq. were obtained.

[0218] Production of thermosetting compounds:

[0219] Compositions Z1 to Z18:

[0220] For each composition, the ingredients of component K1 listed in Tables 1 to 3 were mixed in the specified quantities (in parts by weight) using a centrifugal mixer (Thinky ARE-250, 2000 U / rnin, 60 s) and stored in a sealed container.

[0221] Socal® U1S2 (from Imerys), a precipitated and stearate-coated calcium carbonate, was used as the "precipitated CaCOs".

[0222] Monarch® 570 (from Cabot) was used as the "Russ".

[0223] Furthermore, the ingredients of component K2 listed in Tables 1 to 3 were mixed in the specified quantities (in parts by weight) and stored in a sealed container.

[0224] Subsequently, the components K1 and K2 of each composition were mixed using the centrifugal mixer and tested as described below.

[0225] The Tack Free Time (TFT) was determined by applying 20 g of the mixed composition to cardboard in a layer thickness of approximately 2 mm and measuring, under standard climate conditions, the time until, upon light tapping of the surface of the applied composition with an LDPE pipette, no residue remained on the pipette.

[0226] To determine the mechanical properties, the mixed composition was applied to a silicone-coated release paper to form a 2 mm thick film. This film was cured for 7 days under standard climatic conditions. Several dumbbell-shaped test specimens, 75 mm long with a 30 mm web length and 4 mm web width, were punched out of the film and tested according to DIN EN 53504 at a tensile speed of 200 mm / min for tensile strength, elongation at break, modulus of elasticity at 5% (at 0.5–5% elongation), and modulus of elasticity at 50% (at 0.5–50% elongation). Additionally, several test specimens were punched out to determine the tear resistance and tested according to DIN ISO 34-1, Method B (angled test specimen) at a tensile speed of 500 mm / min. The Shore A hardness was determined according to DIN 53505 on test specimens (diameter 20 mm, thickness 5 mm) hardened for 7 days under standard climatic conditions. These results are marked with the suffix "7d NK".To determine resistance to heat and water, further Shore A test specimens were cured for 7 days under standard climate conditions and then either stored for an additional 7 days in a convection oven at 100 °C, or for an additional 7 days at 70 °C and 100% relative humidity. The Shore A hardness of each specimen was then determined after cooling to room temperature. These results are marked with the suffix "+7d 100°C" or "+7d 70 / 100".

[0227] All compositions cured completely odorless. Each resulted in an elastic polymer with a smooth, non-sticky surface.

[0228] The results are given in Tables 1 to 3.

[0229] The compounds marked with "(Ref.)" are comparative examples.

[0230]

[0231] Table 1: Composition and properties of Z1 to Z8.

[0232] 11,8-Diazabicyclo[5.4.0]undec-7-ene (Lupragen® N700, from BASF) 2 Ratio of the number of acetoacetate groups to the number of aldimine groups

[0233] Table 1 shows that the compositions Z1 to Z6 according to the invention cured to an elastic polymer in the stoichiometry range of 1 to 3.5 acetoacetate groups per aldimine group. The comparison compositions Z7 and Z8 with an aldehyde-functional polymer also cured to an elastic polymer, but the elongation and tensile strength were significantly lower.

[0234] >

[0235]

[0236] Table 2: Composition and properties of Z4 and Z9 to Z14.

[0237] 1 Ratio of the number of acetoacetate groups to the number of aldimine groups

[0238] Table 2 shows that the compositions Z4 and Z9 to Z11 according to the invention exhibited a short time to tackiness, high tensile strength, high moduli of elasticity and high elongation, whereas the comparison composition Z12 (Ref.), in which the end groups do not correspond to formula (I), exhibited a much longer time to tackiness, lower tensile strength, lower moduli of elasticity and lower elongation.

[0239] Likewise, a comparison of the inventive composition Z13 based on the linear polymer A5 with the comparison composition Z14 based on the linear polymer R2, in which the end groups do not correspond to formula (I), showed a shorter time to tack-free, a higher tensile strength, higher moduli of elasticity and a slightly higher elongation.

[0240]

[0241] Table 3: Composition and properties of Z15 to Z18.

[0242] 1 Ratio of the number of acetoacetate groups to the number of aldimine groups

Claims

1. Patent claims:

1. Hardenable composition comprising - at least one polymer with end groups of formula (I) and an average molecular weight M n from 1,000 to 30,000 g / mol, O -AH -A (L) where X for O, S or NR 1 and R 1 stands for H or a monovalent hydrocarbon residue with 1 to 18 C atoms, and A stands for a monovalent organic residue with 7 to 30 carbon atoms, containing an aromatic aldimine group, and - at least one compound with two or more 1,3-ketoester groups of formula (II), OO -0A R2 <"> where R 2 stands for a monovalent hydrocarbon residue with 1 to 6 carbon atoms.

2. Hardenable composition according to claim 1, characterized in that the ratio of the number of 1,3-ketoester groups of formula (II) to the number of end groups of formula (I) is 1 to 4.

3. Curable composition according to claim 1 or 2, characterized in that the polymer with end groups of formula (I) has an average aldimine functionality of 1.5 to 4, preferably 1.8 to 3, in particular 2 to 3.

4. A curable composition according to any one of claims 1 to 3, characterized in that the polymer with end groups of formula (I) has a polyether backbone.

5. A curable composition according to any one of claims 1 to 4, characterized in that X represents 0.

6. A hardenable composition according to any one of claims 1 to 5, characterized in that A is used in the end groups of formula (I) for a residue of formula G. 1 — N=CH — Z or G 2 — CH=N— R 3 stands, whereby G 1stands for a divalent aliphatic, cycloaliphatic or arylaliphatic hydrocarbon residue, optionally containing ether oxygen, with 2 to 18 C atoms, Z stands for an aromatic or heteroaromatic five- or six-membered ring, which may be substituted and / or fused and comprises a total of 4 to 25 C atoms, G 2 for a divalent, possibly oxygen-containing, arylaliphatic hydrocarbon residue with 5 to 12 C atoms, which is bonded to X via an aliphatic C atom and to CH=N via an aromatic or heteroaromatic ring, and R 3 stands for a monovalent, possibly ether-oxygen-containing aliphatic, cycloaliphatic or arylaliphatic hydrocarbon residue with 1 to 13 C atoms.

7. Curable composition according to one of claims 1 to 6, characterized in that the polymer with end groups of formula (I) is obtained by reacting an isocyanate group-containing polymer with an aldimine of formula HX— A in a ratio of the number of moles of isocyanate groups to the number of moles of aldimine of formula HX— A of at least 1.

8. Curable composition according to any one of claims 1 to 7, characterized in that the compound with two or more 1,3-keto ester groups of formula (II) has a molecular weight or, in the case of an oligomeric or polymeric mixture of compounds with two or more 1,3-keto ester groups of formula (II), an average molecular weight M n from 230 to 10,000 g / mol, preferably 250 to 6,000 g / mol, in particular 500 to 3,000 g / mol.

9. A hardenable composition according to any one of claims 1 to 8, characterized in that R 2in formula (II) stands for methyl and the ketoester groups of formula (II) are therefore acetoacetate groups.

10. A hardenable composition according to any one of claims 1 to 9, characterized in that the compound comprising two or more 1,3-keto ester groups of formula (II) is selected from the group 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'-iso- propylidene-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, the triacetoacetate of propoxylated 1,1,1-trimethylolpropane with an overall average molecular weight Mn from 500 to 2,000 g / mol, poly(oxy-1,2-propylene)diol diacetoacetate with medium molecular weight M n from 600 to 5,000 g / mol, poly(oxy-1,2-propylene)trioltriacetoacetate with medium molecular weight M n poly(oxy-1,2-propylene)triol triacetoacetate containing ethylene oxide units, with a medium molecular weight M, from 2,000 to 6,000 g / mol n from 2,000 to 6,000 g / mol, dimer fatty acid-based polyesterdiol diacetoacetate with medium molecular weight M n from 1,000 to 2,500 g / mol, trimer fatty acid-based polyester triol triacetoacetate with medium molecular weight M n from 1,000 to 3,000 g / mol, castor oil diacetoacetate and castor oil triacetoacetate.

11. Curable composition according to any one of claims 1 to 10, characterized in that, based on the total composition, it contains less than 10 wt%, preferably less than 5 wt%, in particular less than 1 wt%, volatile organic solvents with a boiling point at normal pressure of less than 250 °C and less than 10 wt%, preferably less than 5 wt%, in particular less than 2 wt%, water.

12. Curable composition according to any one of claims 1 to 11, characterized in that the composition is used as a two-component composition comprising two separately packaged components, wherein the polymers with end groups of formula (I) are a component of the first component and the compounds with two or more 1,3-ketoester groups of formula (II) are a component of the second component.

13. Cured composition obtained from the curable composition according to one of claims 1 to 12 after mixing the ingredients or components.

14. Cured composition according to claim 13, characterized in that the tensile strength is at least 4 MPa and / or the elongation at break is at least 200%, in particular at least 300%, determined according to DIN EN 53504 at a tensile speed of 200 mm / min on dumbbell-shaped test specimens with a thickness of 2 mm and a length of 75 mm with a web length of 30 mm and a web width of 4 mm.

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 of the composition are mixed together and the mixed composition is applied in liquid form to at least one substrate.

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