Room temperature curable polymer composition consisting of polyaldehyde and polycyanoacetate

Abstract

The present invention relates to a curable composition comprising:-a first component comprising an aldehyde group-containing compound comprising at least one compound having two or more aldehyde groups, and-a second component comprising a cyanoacetate group-containing compound comprising at least one compound having two or more aldehyde groups, the cyanoacetate group-containing compound comprises at least one compound having two or more cyanoacetate groups, and wherein the first component and the second component have an average molecular weight Mn in the range of 400 to 20000 g / mol in terms of the aldehyde group-containing compound or the cyanoacetate group-containing compound, and the average functionality of at least one of the two components is greater than 2.0 in terms of the aldehyde group-containing compound or the cyanoacetate group-containing compound. The composition is substantially free of toxic components and cures rapidly and without defects under ambient conditions using common catalysts to form non-viscous elastomeric polymers having high strength, high ductility and high tear propagation resistance. It is particularly suitable for use as elastic adhesives, sealants or coatings having high robustness during production, storage and processing and high durability after curing.

Description

Technical Field

[0001] The invention relates to two-component compositions and their use as adhesives, sealants or coatings curable at room temperature. Background Art

[0002] Reactive polymer compositions are known which are curable at room temperature and can be used as adhesives, sealants or coatings with elastic properties. Polyurethane systems which cure by reaction of isocyanate groups with polyols and / or moisture and form particularly highly elastic polymers are widely used. The formulation, preparation and use of polyurethane systems pose a series of challenges in practice. They usually contain significant amounts of monomeric diisocyanates, which can have an irritating effect on the eyes, skin and mucous membranes. The moisture sensitivity of the isocyanate groups can lead to premature crosslinking reactions with an increase in viscosity and even gelation, thus impairing durability or storage stability. For systems formulated in one component, the water required for curing must be introduced from the outside in the form of air moisture, making it difficult to apply in thick layers or between waterproof substrates. For two-component systems with a polyol component and an isocyanate component, there is the problem that the isocyanate groups can react not only with the hydroxyl groups of the polyols, but also with the water that is optionally present. In particular, in the case of high ambient humidity, this can trigger bubble formation and lead to incomplete polymerization and chain scission due to only partially reacted bound polyols, resulting in a more or less loss of strength and elasticity. These problems rarely occur when using mercury catalysts, which catalyze the reaction with polyols with high selectivity. However, mercury catalysts have not been used for a long time due to their high toxicity. As an alternative, two-component polyurethanes are usually catalyzed with tin compounds and / or tertiary amines, but these catalysts have significantly lower selectivity and can therefore generate bubbles, especially at high ambient humidity. Bismuth or zirconium catalysts have higher selectivity; however, they and other alternative metal catalysts are very sensitive to hydrolysis, whereby the catalytic activity is greatly lost, which in turn can lead to curing defects.

[0003] Reactive polymer compositions based on silane-functional polymers (SMP / STP) and silicone resins are also widely used. These polymer systems cure by hydrolysis and condensation of silane groups, releasing alcohols (mainly methanol or ethanol) or oximes, which are toxic and lead to VOC-emissions; in addition, they usually contain a large amount of low molecular weight silanes as crosslinkers or desiccants, which are also harmful to health. Due to the moisture sensitivity of the silane groups, these polymer systems are also very demanding in terms of preparation and use, and do not always achieve the desired results. Also known are water-based polymer systems, which are usually based on acrylate dispersions or polyurethane dispersions. These water-based polymer systems cure by evaporation and coalescence of water and are essentially free of chemically reactive groups. However, they can only be used in relatively thin layers and can only be used between open-porous substrates, the curing speed is highly dependent on the ambient humidity, and has high shrinkage. After curing, due to the inclusion of surfactants required for the preparation and stabilization of the dispersion, water sensitivity increases, which may lead to reduced durability, especially in outdoor applications.

[0004] US2020 / 0257202 describes the reaction of polymer dicyanoacetates with aromatic dialdehydes in a solvent and the application of the resulting solution to glass to produce an adhesive film. Summary of the invention

[0005] It is therefore an object of the present invention to provide novel room temperature curable polymer compositions which are suitable as elastic adhesives, sealants or coatings and which overcome the disadvantages of the known polymer systems.

[0006] Surprisingly, the object is achieved by a curable composition according to claim 1. The composition comprises a first component containing an aldehyde-containing compound and a second component containing a cyanoacetate-containing compound, wherein the first component and the second component have an average molecular weight M of the aldehyde-containing compound or the cyanoacetate-containing compound. n In the range of 400 to 20000 g / mol, and wherein at least one of the two components has an average functionality of greater than 2.0 based on the aldehyde-containing compound or the cyanoacetate-containing compound. The composition has a number of advantageous and surprising properties relative to polymer systems curable at room temperature according to the prior art.

[0007] Both aldehyde-containing compounds and cyanoacetate-containing compounds are low-toxic substances, do not require hazard labels, and can be handled without special precautions. The composition of the present invention is insensitive to moisture and bubble formation, and can achieve a high degree of freedom during preparation, because additives commonly used in curable compositions can be used in two components without causing problems with the storage stability of each component. Therefore, the mixing ratio of the two components can be adjusted almost at will, which can achieve a large degree of freedom in the processing method. The composition is easy to process under ambient conditions, does not require organic solvents to dissolve or dilute the components, and does not require water to emulsify or disperse the components. Regardless of humidity, the composition unexpectedly cures quickly and flawlessly under ambient conditions and does not cause emissions. It is particularly advantageous here that the curing speed can be well controlled using common catalysts (particularly non-metallic bases such as tertiary amines, amidines or guanidines). Non-viscous elastic polymers with high strength and surprisingly high ductility, good heat resistance and water resistance are produced by curing. It is particularly noteworthy that the cured polymer has an extremely high tear propagation strength (Weiterreissfestigkeit), which makes it particularly resistant to huge mechanical stress. Due to this combination of advantageous properties, the compositions according to the invention can be handled particularly simply without special protective measures during the preparation and storage of the components, during use under a wide range of ambient conditions and application conditions, and also after curing under mechanical, thermal or chemical stresses and have a high degree of robustness and a long service life.

[0008] The compositions of the invention are therefore very suitable for use as high-quality elastic adhesives, sealants or coatings. Further aspects of the invention are the subject matter of further independent claims. Particularly preferred embodiments of the invention are the subject matter of the dependent claims.

[0009] Specific embodiments of the invention

[0010] The subject of the present invention is a curable composition comprising:

[0011] - a first component containing an aldehyde group-containing compound, the aldehyde group-containing compound comprising at least one compound having two or more aldehyde groups, and

[0012] - a second component containing a cyanoacetate group-containing compound, wherein the cyanoacetate group-containing compound comprises at least one compound having two or more cyanoacetate groups,

[0013] The average molecular weight M of the first component and the second component is calculated as the aldehyde-containing compound or the cyanoacetate-containing compound n In the range of 400 to 20000 g / mol, at least one of the two components has an average functionality of more than 2.0 based on the aldehyde group-containing compound or the cyanoacetate group-containing compound.

[0014] "Aldehyde" means the formula functional groups.

[0015] "Cyanoacetate group" represents the formula bonded by a dotted line functional groups.

[0016] "Molecular weight" refers to the molar mass of a molecule (in grams / mole). "Average molecular weight" refers to the number average molecular weight (M) of a polydisperse mixture of oligomeric or polymeric molecules. n ). Average molecular weights were determined by gel permeation chromatography (GPC) relative to polystyrene standards.

[0017] "Storage stable" means that the composition can be stored in a suitable container at room temperature for a prolonged period of time, generally at least 3 months to 6 months and longer, without its application properties or use properties changing during storage to an extent relevant to its use.

[0018] Substance names beginning with "poly", such as polycyanoacetate, polyaldehyde or polyol, indicate substances that formally contain two or more of the functional groups appearing in their names per molecule.

[0019] "Room temperature" means a temperature of 23°C.

[0020] All industrial standards or specifications mentioned herein relate to the version valid at the time of the first application submission. Unless otherwise stated, weight percentage (wt%) indicates the mass content of a component in a composition or molecule based on the entire composition or based on the entire molecule. The terms "mass" and "weight" are used synonymously herein.

[0021] The first component and the second component of the cured composition are themselves storage-stable and are stored in separate containers and are not mixed with one another until immediately before or during application.

[0022] The curable composition is preferably non-aqueous. It is preferably substantially free of water or contains only a small amount of water. The composition cures rapidly regardless of the ambient humidity, can be applied in thick layers and / or used between waterproof substrates, and shows little shrinkage during curing.

[0023] Preferably, the curable composition comprises less than 10% by weight, preferably less than 5% by weight, in particular less than 2% by weight, of water, based on the entire composition.

[0024] In a preferred embodiment of the present invention, the composition contains a small amount of water. Water acts as a curing accelerator. For this purpose, the amount of water is 0.05% to 5% by weight, in particular 0.1% to 2% by weight, based on the entire composition.

[0025] Curable composition preferably does not contain the aldehyde-containing compound or the cyanoacetate-containing compound in the form of emulsion or dispersion.Therefore, the compound with aldehyde group or cyanoacetate group contained preferably does not contain ionic group or its precursor substantially, and does not contain the long poly (oxyethylene) chain common in surfactant substantially.Described composition has high water resistance.Especially, based on aldehyde-containing compound or cyanoacetate-containing compound, the content of acid group or ionic group of aldehyde-containing compound of first component and cyanoacetate-containing compound of second component separately is less than 0.1 weight %, preferably less than 0.05 weight %.Ionic group is particularly carboxylate group, ammonium group or sulfonate group.

[0026] In the curable composition, the average molecular weight M of the first component and the second component in terms of the aldehyde-containing compound or the cyanoacetate-containing compound is n In the range of 400 to 20000 g / mol. This enables polymers with high ductility to be obtained.

[0027] Preferably, at least one of the two components has an average molecular weight M in the range of 1000 to 20000 g / mol, preferably 1500 to 15000 g / mol, in particular 2000 to 10000 g / mol, based on the aldehyde-containing compound or the cyanoacetate-containing compound. n This enables particularly high ductility to be achieved.

[0028] In the curable composition, at least one of the two components has an average functionality, calculated as aldehyde or cyanoacetate groups, greater than 2.0. When the average aldehyde functionality of the first component is 2.0 or less, then the cyanoacetate functionality of the second component must be greater than 2.0. And when the average cyanoacetate functionality of the second component is 2.0 or less, then the average aldehyde functionality of the first component must be greater than 2.0. This composition cures to form an elastic polymer having high strength and durability.

[0029] Particularly preferably, the average aldehyde functionality of the first component and the average cyanoacetate functionality of the second component are both greater than 2.0, in particular 2.2 to 3.0. This enables polymers with high strength and durability but also good ductility.

[0030] The compound having two or more aldehyde groups is preferably liquid at room temperature. In particular, it is measured by a cone-plate viscometer (cone diameter 10 mm, cone angle 1°, distance from cone tip to plate 0.05 mm, shear rate 10 s -1) at 20° C., measured by HPLC, is 0.2 to 700 Pa·s, preferably 0.3 to 500 Pa·s, particularly preferably 0.5 to 200 Pa·s (especially 1 to 100 Pa·s), while for viscosities of less than 1 Pa·s a 50 mm cone diameter is used. These compounds are easy to handle at ambient temperature even without the addition of solvents or diluents.

[0031] Preferred as the aldehyde group-containing compound are polymers having aldehyde groups.

[0032] Preferably, the first component has an average molecular weight M of 1:1, calculated as the aldehyde-containing compound, measured by gel permeation chromatography (GPC) relative to polystyrene standards. n In the range of 1000 to 20000 g / mol, preferably 1500 to 15000 g / mol, in particular 2000 to 10000 g / mol. Even without adding solvents or diluents, the components are easy to handle at ambient temperature and enable polymers with high ductility and elasticity to be achieved.

[0033] Preferably, the average aldehyde functionality of the aldehyde-containing compounds in the first component is in the range of 1.6 to 4, preferably 1.8 to 3.5, more preferably 2.0 to 3.0, especially 2.2 to 3.0. This enables a cured composition with high ductility, strength and durability to be achieved.

[0034] Preferably, the aldehyde group-containing compound comprises a polymer having a polymer backbone and the polymer backbone comprises poly(oxyalkylene) units and / or polyester units.

[0035] Preferred poly(oxyalkylene)s are poly(oxyethylene), poly(oxy-1,2-propylene), poly(oxy-1,3-propylene), poly(oxy-1,4-butylene), poly(oxy-1,2-butylene) or mixtures of these poly(oxyalkylene). Preferred among these are poly(oxy-1,2-propylene), poly(oxy-1,3-propylene) or poly(oxy-1,4-butylene), in particular poly(oxy-1,2-propylene), wherein the poly(oxyethylene) units may be present in an amount of 0% to 25% by weight, based on the poly(oxyalkylene) backbone, in particular at the chain ends. Aldehyde-functional polymers having such backbones have low viscosity and are therefore particularly easy to handle and are particularly hydrophobic. They allow compositions having particularly good processability, high ductility and good water resistance to be achieved.

[0036] Preferred polyesters are esters of dicarboxylic acids and diols or triols, triglycerides or polyesters based on dimerized or trimerized fatty acids. Particularly preferred are polyesters of dimerized fatty acids or polyesters derived from castor oil, castor oil derivatives or vegetable oils. Aldehyde-functional polymers with such a backbone are particularly hydrophobic and enable compositions with particularly good heat and water resistance to be achieved. They are also based on renewable raw materials and are therefore particularly sustainable.

[0037] The compound having two or more aldehyde groups preferably also contains urethane groups. Compositions having particularly high ductility and particularly high tear propagation strength are thereby obtained.

[0038] Preferably, the aldehyde-containing compound comprises a polymer containing urethane groups which is liquid at room temperature and has an average molecular weight M of n The average aldehyde functionality is 1.8 to 3.5, preferably 2.0 to 3.0, especially 2.2 to 3.0.

[0039] Preferably, the compound having two or more aldehyde groups is obtained by reaction of at least one hydroxyaldehyde with at least one isocyanate group-containing polymer or at least one polyisocyanate.

[0040] Suitable hydroxyaldehydes are in particular compounds having a molecular weight in the range from 60 to 500 g / mol, preferably from 60 to 250 g / mol.

[0041] Particularly suitable are 2-hydroxyacetaldehyde, 3-hydroxybutyraldehyde, 3-hydroxypivalaldehyde, 5-hydroxyvaleraldehyde, 2-(2-hydroxyethoxy)acetaldehyde, 3-(2-hydroxyethoxy)propionaldehyde, 5-hydroxymethylfurfural, alkoxylated o-, m- or p-hydroxybenzaldehyde or alkoxylated vanillin, where "alkoxylation" preferably means (one or more times) "ethoxylation" or "propoxylation", and 4,4'-(2-hydroxypropane-1,3-diyl)-bis(oxy)-bis(benzaldehyde) or 4,4'-(2-hydroxypropane-1,3-diyl)-bis(oxy)-bis(3-methoxybenzaldehyde).

[0042] Preferred are ethoxylated salicylaldehydes, in particular 2-(2-hydroxyethoxy)benzaldehyde, ethoxylated vanillins, in particular 4-(2-hydroxyethoxy)-3-methoxybenzaldehyde, or 5-hydroxymethylfurfural. These hydroxyaldehydes are obtainable by simple processes, enable the production of aldehyde-containing compounds having low viscosity and therefore easy handling, and compositions having good processability, high strength and very high ductility.

[0043] Particularly preferred as hydroxyaldehyde is 5-hydroxymethylfurfural. These hydroxyaldehydes are obtained from renewable raw materials and surprisingly allow the production of aldehyde-containing compounds with particularly low viscosity and curable compositions with particularly good processability and high strength, ductility, tear propagation strength, heat resistance and water resistance.

[0044] Suitable polymers containing isocyanate groups for preparing compounds having two or more aldehyde groups are in particular reaction products of polyols with diisocyanates, in particular in an NCO / OH molar ratio of 1.5 / 1 to 10 / 1, wherein unreacted monomeric diisocyanates are optionally removed from the polymer.

[0045] The isocyanate group-containing polymer preferably has a free isocyanate group content in the range from 0.5 to 15% by weight, particularly preferably from 1 to 10% by weight and in particular from 1.5 to 6% by weight, based on the polymer.

[0046] Very particularly preferred as isocyanate group-containing polymer is the reaction product of at least one diisocyanate and at least one polyol in an NCO / OH ratio of at least 3 / 1, preferably from 3 / 1 to 10 / 1, in particular from 4 / 1 to 8 / 1, after which the majority of the monomeric diisocyanate is removed by suitable separation methods, so that the isocyanate group-containing polymer finally has a monomeric diisocyanate content of at most 0.2% by weight, based on the polymer. Such isocyanate group-containing polymers allow aldehyde-functional polymers to have a particularly low content of reaction products from monomeric diisocyanates and hydroxyaldehydes, in particular less than 0.5% by weight of such reaction products, based on the aldehyde-functional polymer. This allows the realization of curable compositions having particularly simple processing, long open times, rapid curing and particularly good flexibility.

[0047] Suitable diisocyanates include, in particular, 1,6-hexamethylene diisocyanate (HDI), 2,2(4),4-trimethyl-1,6-hexamethylene diisocyanate (TMDI), 1-methyl-2,4(6)-diisocyanatocyclohexane (H6TDI), isophorone diisocyanate (IPDI), 4,4'-diisocyanatodicyclohexylmethane (H 12 MDI), 4(2),4'-diphenylmethane diisocyanate (MDI) or 2,4(6)-toluene diisocyanate. Preference is given to HDI, IPDI, TDI or MDI. Particular preference is given to IPDI. This results in a particularly easy-to-process composition which cures to form a polymer having high strength and ductility.

[0048] Suitable polyols are in particular

[0049] - polyether polyols, in particular polyoxyalkylene diols or triols, in particular the 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, which can be polymerized with the aid of starter molecules having two or more active hydrogen atoms, in particular water, ammonia or compounds having a plurality of OH groups or NH groups, for example 1, 2-ethanediol, 1,2- or 1,3-propylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, isomeric dipropylene glycol or tripropylene glycol, isomeric butanediols, pentanediol, hexanediol, heptanediol, octanediol, nonanediol, decanediol, undecanediol, 1,3- or 1,4-cyclohexanedimethanol, bisphenol A, hydrogenated bisphenol A, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol or aniline, or mixtures thereof.

[0050] Preferred polyether polyols are polyoxypropylene diols or triols, or so-called ethylene oxide-terminated (EO-terminated or EO-terminated) polyoxypropylene diols or triols. The latter are polyoxyethylene-polyoxypropylene mixed polyols which are obtained, in particular, by further alkoxylating polyoxypropylene diols or triols with ethylene oxide after the polypropoxylation reaction has ended, thereby giving them primary hydroxyl groups.

[0051] Preferred polyether polyols have an unsaturation of less than 0.02 mEq / g, in particular less than 0.01 mEq / g.

[0052] Polyester polyols, in particular polyester polyols obtained by polycondensation of hydroxycarboxylic acids or lactones or of aliphatic and / or aromatic polycarboxylic acids with diols or polyols. Preference is given to amorphous polyester polyols based on dimerized or trimerized fatty acids, such as those commercially available from Croda.

[0053] - Polycarbonate polyols, obtainable, for example, by reaction of diols with dialkyl carbonates, diaryl carbonates or phosgene.

[0054] - block copolymers bearing at least two hydroxyl groups, in particular polyether polyester polyols.

[0055] - Polyacrylate polyols and polymethacrylate polyols.

[0056] - polyhydroxy-functional fats or oils, in particular natural fats or oils (for example, in particular castor oil, castor oil derivatives); or so-called oleochemical polyols obtained by chemical modification of natural fats and oils, for example Hydroxylated vegetable oils available under the trade name HYDROGENOL® (from BASF).

[0057] - Polyolefin polyols, such as, in particular, polyhydroxy-functional polyolefins, polyisobutylenes, polyisoprenes; polyhydroxy-functional ethylene-propylene copolymers, ethylene-butylene copolymers or ethylene-propylene-diene copolymers, such as those prepared by Kraton Polymers; polyhydroxy-functional diene (especially 1,3-butadiene) polymers, which can also be prepared by anionic polymerization; copolymers of polyhydroxy-functional dienes (for example 1,3-butadiene or diene mixtures) and vinyl monomers (for example styrene, acrylonitrile, vinyl chloride, vinyl acetate, vinyl alcohol, isobutylene and isoprene), such as polyhydroxy-functional acrylonitrile / butadiene copolymers, such as acrylonitrile / butadiene copolymers terminated, for example, by epoxides or amino alcohols and carboxyl groups (for example, those known under the name CTBN or CTBNX or ETBN commercially available from Emerald Performance Materials); and hydrogenated polyhydroxy-functional diene polymers or copolymers.

[0058] Preferred are polyols that are liquid at room temperature.

[0059] Preference is given to polyols having an OH number in the range from 9 to 115 mg KOH / g, preferably from 14 to 60 mg KOH / g, in particular from 18 to 40 mg KOH / g.

[0060] Particularly preferred are polyether polyols, polyester polyols based on dimerized or trimerized fatty acids, castor oil, castor oil derivatives or hydroxylated vegetable oils. Most preferred are polyether polyols.

[0061] Likewise suitable as compounds having two or more aldehyde groups are the reaction products of at least one polyisocyanate with at least one hydroxyaldehyde, in particular the abovementioned hydroxyaldehydes.

[0062] Suitable polyisocyanates are in particular oligomeric diisocyanates, in particular HDI-biuret, such as N 100 or N 3200 (from Covestro), HDB or HDB-LV (from Vencorex) or 24A-100 (from Asahi Kasei); HDI-isocyanurate, such as N 3300, N3600 or N 3790BA (all from Covestro), HDT, HDT-LV or HDT-LV2 (from Vencorex), TPA-100 or THA-100 (from Asahi Kasei) or HX (from Nippon Polyurethane); HDI-uretdione, such as N 3400 (from Covestro); HDI-iminooxadiazinedione, such as XP 2410 (from Covestro); HDI-allophanates, such as VP LS2102 (from Covestro); IPDI-isocyanurate, as a solution Z 4470 (from Covestro) or solid form T1890 / 100 (from Evonik); TDI-oligomers, such as IL (from Covestro); or mixed isocyanurates based on TDI / HDI, such as HL (from Covestro), where "HDI" stands for 1,6-hexane diisocyanate, "IPDI" stands for isophorone diisocyanate and "TDI" stands for 2,4-toluene diisocyanate or a mixture thereof with 2,6-toluene diisocyanate. Preference is given to oligomeric diisocyanates derived from HDI, in particular HDI-biuret.

[0063] Preferably, the isocyanate group-containing polymer or polyisocyanate and the hydroxyaldehyde are reacted at a temperature of 40 to 140° C., preferably 60 to 120° C., optionally in the presence of a suitable catalyst, in an OH / NCO ratio of 1 / 1 to 1.2 / 1.

[0064] The curable composition contains at least one compound having two or more cyanoacetate groups as a component of the second component.

[0065] The compound having two or more cyanoacetate groups is preferably liquid at room temperature. In particular, it is measured by a cone-plate viscometer (cone diameter 10 mm, cone angle 1°, distance from cone tip to plate 0.05 mm, shear rate 10 s -1 ) at 20° C., measured by 0.1 to 100 Pa·s, preferably 0.2 to 50 Pa·s, in particular 0.5 to 20 Pa·s, while for viscosities of less than 1 Pa·s a 50 mm cone diameter is used. These compounds are easy to handle at ambient temperature even without the addition of solvents or diluents and enable easy-to-process compositions to be achieved.

[0066] Preferably, the average functionality of the second component, based on the cyanoacetate group-containing compound, is in the range of 1.6 to 4, preferably 1.8 to 3.5, particularly preferably 2.0 to 3.0, in particular 2.3 to 3.0. This enables a cured composition having high ductility, strength and durability to be achieved.

[0067] Preferably, the average molecular weight M of the second component as a cyanoacetate-containing compound is n In the range of 400 to 10000 g / mol, preferably 500 to 2000 g / mol.

[0068] In a preferred embodiment of the present invention, the average molecular weight M of the second component n In the range of 500 to 2000 g / mol. Such a second component enables a particularly easy to process composition with high strength.

[0069] In another preferred embodiment of the present invention, the average molecular weight M of the second component, calculated as the cyanoacetate group-containing compound, is n In the range of 2000 to 10000 g / mol. The first component (the first component has a similar high average molecular weight M based on the aldehyde-containing compound) n ), this second component makes it possible in a particularly simple manner to achieve a composition in which the two components have a mixing ratio of 1:1, which is particularly advantageous in certain applications (particularly in the case of processing with the aid of a static mixer).

[0070] Particularly preferably, the second component comprises at least one n A cyanoacetate-functional polymer having an average cyanoacetate functionality of 400 to 10,000 g / mol, preferably 500 to 2,000 g / mol, and an average cyanoacetate functionality of 1.8 to 3.5, particularly preferably 2.0 to 3.0, in particular 2.5 to 3.0.

[0071] Preferably, the compound having at least two cyanoacetate groups is obtained by transesterification of at least one cyanoacetate of the formula (I) with at least one polyfunctional alcohol, during which an alcohol of the formula R—OH is released and removed,

[0072]

[0073] Where R represents C 1-6 alkyl.

[0074] Preferably, R represents methyl, ethyl or tert-butyl, in particular ethyl.

[0075] Preferably, the reaction is carried out, optionally under reduced pressure and optionally in the presence of a catalyst, at a temperature in the range from 50 to 150° C., with simultaneous distillative removal of the liberated alcohol R—OH.

[0076] Suitable polyfunctional alcohols are commercially available compounds or polymers having two or more OH groups, such as, in particular, 1,2-ethanediol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, diethylene glycol, dipropylene glycol, 1,1,1-trimethylolpropane, glycerol, ethoxylated or in particular propoxylated glycerol, ethoxylated or in particular propoxylated 1 , 1,1-trimethylolpropane, castor oil, ethoxylated or in particular propoxylated castor oil, ketone resin-modified castor oil, hydroxylated vegetable oils, dimerized fatty acid diols or trimerized fatty acid triols, amorphous polyester diols or triols based on dimerized or trimerized fatty acids, and the other polyols already mentioned above for the preparation of polymers containing isocyanate groups, in particular poly(oxy-1,2-propylene) diols or triols or ethylene oxide-terminated poly(oxy-1,2-propylene) diols or triols.

[0077] Particularly preferred polyfunctional alcohols are those having an average molecular weight M n 300 to 1700 g / mol of propoxylated 1,1,1-trimethylolpropane. Other particularly preferred polyfunctional alcohols are n 2000 to 10000 g / mol of poly(oxy-1,2-propylene) diols or triols, wherein these alcohols are optionally end-capped with ethylene oxide.

[0078] Other particularly preferred polyfunctional alcohols are those having an average molecular weight M n 800 to 4000 g / mol of an amorphous polyester diol based on a dimerized fatty acid or an amorphous polyester triol based on a trimerized fatty acid.

[0079] Particularly preferably, the cyanoacetate group-containing compound comprises at least one cyanoacetate-functional polymer selected from the group consisting of polymers with an average molecular weight M n Propoxylated 1,1,1-trimethylolpropane-tri(cyanoacetate) with an average molecular weight of 500 to 2000 g / mol n Poly(oxy-1,2-propylene)diol-bis(cyanoacetate) having an average molecular weight M of 2000 to 10000 g / mol n Poly(oxy-1,2-propylene)triol-tri(cyanoacetate) with an average molecular weight of 2000 to 10000 g / mol n Poly(oxy-1,2-propylene)diol-bis(cyanoacetate) containing ethylene oxide units, with an average molecular weight M of 2000 to 10000 g / mol n Poly(oxy-1,2-propylene)triol-tri(cyanoacetate) containing ethylene oxide units, with an average molecular weight M of 2000 to 10000 g / moln A polyester diol-di(cyanoacetate) based on dimer fatty acid of 1000 to 4000 g / mol and an average molecular weight M n 1000 to 4000 g / mol of polyester triol-tris(cyanoacetate) based on trimerized fatty acid.

[0080] Preferably, the overall composition has an average functionality of at least 2.2 based on the aldehyde-containing compounds and cyanoacetate-containing compounds. This means that a composition having an average aldehyde functionality of, for example, 1.8 in the first component is preferably combined with a second component having an average cyanoacetate functionality of at least 2.4, so that an average reactive group functionality of 2.2 is achieved overall.

[0081] Particularly preferably, the curable composition comprises at least one urethane group-containing polymer which is liquid at room temperature as a component of the first component, the average molecular weight M of the urethane group-containing polymer being n 1000 to 20000 g / mol, preferably 1500 to 15000 g / mol, in particular 2000 to 10000 g / mol, an average aldehyde functionality of 1.8 to 3.5, particularly preferably 2.0 to 3.0, in particular 2.2 to 3.0; and contains at least one cyanoacetate group-containing polymer as a component of the second component, the average molecular weight M of the cyanoacetate group-containing polymer n The average cyanoacetate functionality is 1.8 to 3.5, preferably 2.0 to 3.0, in particular 2.5 to 3.0, wherein the average reactive group functionality is preferably at least 2.2 overall.

[0082] The first component of the curable composition may also contain a certain proportion of low molecular weight polyaldehydes, such as, in particular, 1,6-adipaldehyde, 1,7-heptanedialdehyde, 1,8-octanedial, 1,9-nonanedialdehyde, 2-methyl-1,8-octanedial, 1,10-decanedial, 1,11-undecanedialdehyde, 1,12-dodecanedialdehyde, hexahydrophthalaldehyde, hexahydroisophthalaldehyde, hexahydroterephthalaldehyde, octahydro-4,7-methylene-bridged (me thano)-1H-indene dicarboxaldehyde, 3,6,9-trioxaundecane-1,11-dialdehyde, 1,3-bis(2,2-dimethyl-3-oxapropyl)imidazolidin-2-one, N,N'-bis(2,2-dimethyl-3-oxapropyl)piperazine, N,N'-bis(2,2-dimethyl-3-oxapropyl)urea, o-phthalaldehyde, isophthalaldehyde, terephthalaldehyde, 9,10-anthracene dicarboxaldehyde or naphthalene dicarboxaldehyde.

[0083] The second component of the curable composition may also contain a certain proportion of low molecular weight polycyanoacetates, such as, in particular, 1,2-ethylene glycol-bis(cyanoacetate), 1,2-propylene glycol-bis(cyanoacetate), 1,3-propylene glycol-bis(cyanoacetate), 1,4-butylene glycol-bis(cyanoacetate), 1,6-hexanediol-bis(cyanoacetate), 1,4-cyclohexanedimethanol-bis(cyanoacetate), dipropylene glycol-bis(cyanoacetate), 1,1,1-trimethylolpropane-tris(cyanoacetate) or glycerol-tris(cyanoacetate).

[0084] The curable composition may also contain other ingredients, in particular the following:

[0085] fillers, in particular ground or precipitated calcium carbonate, optionally coated with fatty acids, in particular stearates, barite (settled stone), quartz powder, quartz sand, dolomite, wollastonite, kaolin, calcined kaolin, layered silicates such as mica or talc, zeolites, aluminum hydroxide, magnesium hydroxide, silicon dioxide (including highly disperse silicon dioxide from pyrogenic processes), industrially produced carbon black, graphite, metal powders such as aluminum, copper, iron, silver or steel, PVC powder or hollow spheres;

[0086] - fibers, in particular glass fibers, carbon fibers, metal fibers, ceramic fibers, Hanf fibers, cellulose fibers or plastic fibers, for example polyamide fibers or polyethylene fibers;

[0087] - nanofillers such as graphene or carbon nanotubes;

[0088] -dye;

[0089] - pigments, in particular titanium dioxide, chromium oxide, iron oxide and / 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 diisononyl-1,4-cyclohexanedicarboxylate, isophthalates, trimellitates , adipates, in particular dioctyl adipate (DOA), azelates, sebacates, benzoates, glycol ethers, glycol esters, plasticizers with a polyether structure, in particular polypropylene oxide mono-, di- or triols, or polypropylene oxide mono-, di- or triols with blocked hydroxyl groups, in particular in the form of acetate groups, and organic sulfonates or phosphates, in particular diphenylcresyl phosphate (DPK), polybutene, polyisobutene or plasticizers derived from natural fats or oils, in particular epoxidized soybean oil or linseed oil, in particular phthalates, hydrogenated phthalates, adipates or plasticizers with a polyether structure;

[0091] - solvent;

[0092] - modifiers, such as hydrocarbon resins, natural or synthetic waxes or bitumens;

[0093] - rheology modifiers, in particular urea compounds, phyllosilicates such as bentonites, castor oil derivatives, hydrogenated castor oil, polyamides, polyurethanes, pyrogenic silica or hydrophobically modified polyoxyethylenes;

[0094] - Desiccants, in particular molecular sieves, calcium oxide, monooxazolidines such as 2 (from Incorez) or orthoformate;

[0095] - adhesion promoters, in particular titanates or organoalkoxysilanes, for example aminosilanes, mercaptosilanes, epoxysilanes, vinylsilanes, (meth)acryloylsilanes, carbamatesilanes, alkylsilanes, S-(alkylcarbonyl)mercaptosilanes or oligomeric forms of these silanes;

[0096] - a catalyst, in particular a non-metallic base, such as a tertiary amine, in particular 2-dimethylaminoethyl ether, 2,2'-bismorpholine diethyl ether (DMDEE) or 1,4-diazabicyclo[2.2.2]octane (DABCO), an amidine, in particular 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) or 1-(2-hydroxy-3-(3-trimethoxysilylpropoxy)prop-1-yl)-2-methyl-1,4,5,6-tetrahydropyrimidine, or a guanidine, in particular 1,1,3,3-tetramethylguanidine, 1-hexyl-2,3-diisopropylguanidine or a ... n about 250 to 500 g / mol of 1,1′-(α,ω-polyoxypropylene)bis(2,3-diisopropylguanidine), and in particular basic salts, such as in particular potassium acetate, potassium benzoate, potassium carbonate, potassium hydrogencarbonate, potassium phosphate, and the corresponding salts with sodium or lithium instead of potassium, wherein the basic salts are preferably used in the form of aqueous solutions, for example in a salt concentration of 10 to 30% by weight, based on the total weight of the solution;

[0097] - non-reactive thermoplastic polymers, for example homopolymers or copolymers of unsaturated monomers, in particular selected from ethylene, propylene, butylene, isobutylene, isoprene, vinyl acetate and alkyl (meth)acrylates, in particular polyethylene (PE), polypropylene (PP), polyisobutylene, ethylene vinyl acetate copolymers (EVA) and atactic poly-α-olefins (APAO);

[0098] - flame-retardant substances, in particular the fillers already mentioned, such as aluminium hydroxide or magnesium hydroxide, organic phosphates, ammonium polyphosphate, melamine or its derivatives, boron compounds or antimony compounds;

[0099] - additives, in particular wetting agents, leveling agents, defoamers, deaerators, stabilizers against oxidation, heat, light or UV radiation or biocides;

[0100] and other materials commonly used in curable compositions.

[0101] These additives can be present as a component of the first component or the second component. The substance reactive toward cyanoacetate groups is preferably a component of the first component. The substance reactive toward aldehyde groups is preferably a component of the second component.

[0102] The curable composition preferably further comprises at least one other ingredient selected from plasticizers, fillers and catalysts. Preferably, the curable composition comprises a plurality of such other ingredients.

[0103] The curable composition preferably comprises at least one basic catalyst having a pKa of at least 8, preferably at least 8.5, in particular an aqueous solution of a nitrogen-containing compound or a basic salt. Such compositions exhibit particularly rapid curing.

[0104] In a preferred embodiment of the invention, the curable composition comprises 10% to 95% by weight, preferably 20% to 90% by weight, in particular 30% to 80% by weight of filler, based on the total composition. Preference is given to fillers selected from calcium carbonate, barite, quartz powder, quartz sand, kaolin, aluminum hydroxide, titanium dioxide and carbon black. Such a composition is particularly suitable for applications with a layer thickness of at least 1 mm, preferably 1 to 50 mm, in particular 1.5 to 25 mm. In this case, the cured composition exhibits significant elastic properties.

[0105] In another preferred embodiment of the present invention, the curable composition comprises 5 to 80% by weight, in particular 10 to 60% by weight, of a plasticizer, based on the entire composition. Preference is given to plasticizers selected from the group consisting of DINP, DIDP, DPHP, DINCH, bis(2-ethylhexyl)terephthalate, DINT, bis(2-ethylhexyl)-1,4-cyclohexanedicarboxylate, diisononyl-1,4-cyclohexanedicarboxylate, DOA, polypropylene oxide monool, polypropylene oxide diol, polypropylene oxide triol, polypropylene oxide monool acetate, polypropylene oxide diol diacetate, polypropylene oxide triol triacetate and DPK.

[0106] In a particularly preferred embodiment of the invention, the curable composition comprises 20 to 90% by weight, in particular 30 to 80% by weight, of filler, and 5 to 60% by weight, based on the entire composition.

[0107] The curable composition preferably comprises less than 10% by weight, particularly preferably less than 5% by weight and in particular less than 1% by weight, based on the entire composition, of volatile organic solvents having a boiling point of less than 250° C. at standard pressure. The composition causes particularly low emissions.

[0108] The first component of the curable composition preferably does not contain aldimine groups or only contains a small amount of aldimine groups, and relative to each mole of cyanoacetate groups in the second component, comprises less than 0.2mol, particularly less than 0.1mol of aldimine groups. This means that the first component is substantially free of primary amines. Primary amino groups react with aldehydes to form aldimines. It is not within the scope of the present invention to convert the aldehyde groups in the first component into aldimine groups. Compositions of the present invention are mainly cured by the reaction of cyanoacetate groups with free aldehyde groups.

[0109] The curable composition preferably comprises in total:

[0110] - 5% to 100% by weight, preferably 10% to 70% by weight, of the sum of compounds having aldehyde groups or cyanoacetate groups,

[0111] - 0% to 50% by weight, preferably 10% to 40% by weight, of plasticizers,

[0112] - 0% to 90% by weight, preferably 20% to 80% by weight, of fillers,

[0113] - and optionally other substances,

[0114] Based on the entire composition.

[0115] In the curable composition, the ratio of the number of cyanoacetate groups to the number of aldehyde groups is preferably in the range of 0.7 to 1.5, particularly preferably in the range of 0.8 to 1.2, in particular in the range of 0.9 to 1.1. Such a ratio enables rapid, defect-free curing. Particularly preferably, the ratio of the number of cyanoacetate groups to the number of aldehyde groups is in the range of 0.9 to 1.5. Such a ratio enables compositions with particularly high strength.

[0116] The consistency of the first component and the second component of the curable composition is suitably such that these components can be easily mixed with one another by simple methods under ambient conditions. For this purpose, liquid components or pasty components are particularly suitable.

[0117] The first component and the second component of the curable composition are prepared separately from one another. The ingredients of the individual components are mixed with one another to form a macroscopically homogeneous material. Each component is stored in a separate container. Suitable containers are in particular barrels, containers, bottles, buckets, barrels, cans, bags, hose bags, magazines or tubes. The components are storage-stable.

[0118] To use the curable composition, the two components and any other components present are mixed with one another immediately before or during application. The mixing ratio is selected such that the ratio of the number of cyanoacetate groups to the number of aldehyde groups is within a suitable range, in particular about 0.9 to 1.1. The mixing ratio between the first component and the second component is generally within a range of about 100:1 to 1:10, in particular 50:1 to 1:5, in parts by weight.

[0119] If the components are mixed with one another before application, care must be taken not to allow too much time between mixing the components and application, since otherwise the onset of the reaction and the associated increase in viscosity can lead to disturbances such as insufficient flow or slow and incomplete adhesion to the substrate. In particular, the open time of the composition should not be exceeded during application.

[0120] "Open time" here means the time between mixing of the components and the completion of the state of the composition suitable for processing.

[0121] Mixing is preferably carried out at ambient temperature, in particular at a temperature in the range from -5 to 50°C, in particular from 0 to 40°C.

[0122] As the two components are mixed, the composition begins to cure by chemical reaction. Here, mainly the cyanoacetate groups react with the aldehyde groups, so that the composition gradually cures into a solid polymer material. It can be expected that the curing reaction forms a structural unit.

[0123] Curing is preferably carried out at ambient temperature, in particular at a temperature in the range from -5 to 50°C, in particular from 0 to 40°C.

[0124] Another subject of the invention is a cured composition obtained from the curable composition after mixing the two components.

[0125] The cured composition is preferably elastic and has high strength, high ductility and tear propagation resistance.

[0126] The cured composition preferably has a tensile strength, determined as described in the examples to DIN EN 53504, of at least 1 MPa, preferably at least 1.5 MPa, more preferably at least 2 MPa, more preferably at least 2.5 MPa and in particular at least 3 MPa.

[0127] The cured composition preferably has an elongation at break determined as described in the examples to DIN EN 53504 of at least 100%, preferably at least 150%, more preferably at least 200%, more preferably at least 250%, in particular at least 300%.

[0128] The cured composition preferably has a tear propagation strength determined according to DIN ISO 34-1 method B as described in the examples of at least 3 N / mm, preferably at least 5 N / mm, more preferably at least 7 N / mm and in particular at least 10 N / mm.

[0129] Preferably, the cured composition has a Shore A hardness in the range from 10 to 90, in particular from 20 to 80, determined according to DIN 53505 as described in the examples.

[0130] The cured composition also has good heat resistance and water resistance. Preferably, the cured composition exhibits high strength, ductility and hardness even after storage at 100°C or 70°C and 100% relative humidity for 7 days.

[0131] The curable composition is suitable for a variety of uses. It can be used in particular as an adhesive, sealant, coating, casting resin or filler.

[0132] Another subject of the invention is the use of the curable composition as an elastic adhesive, elastic sealant or elastic coating, wherein the first component and the second component and optionally further components are mixed with one another and the mixed composition is applied in liquid form to at least one substrate.

[0133] In the case of use as elastic adhesive, elastic sealant or elastic coating, the layer thickness of the cured composition is preferably at least 1 mm, preferably 1 to 50 mm, in particular 1.5 to 25 mm.

[0134] Suitable substrates are in particular:

[0135] - glass, glass ceramics, concrete, mortar, cement flooring, fiber cement, bricks, tiles, plaster or natural stone such as granite or marble;

[0136] - Repair or levelling materials based on PCC (polymer modified cement mortar) or ECC (epoxy modified cement mortar);

[0137] - metals or alloys, such as aluminium, iron, steel, copper, other non-ferrous metals, including metals or alloys with surface treatments, such as zinc-plated or chromium-plated metals;

[0138] - tar or bitumen;

[0139] - leather, fabric, paper, wood, wooden materials combined with resins (for example phenolic resins, melamine resins or epoxy resins), resin-fabric composites or other so-called polymer composites;

[0140] - plastics, for example hard 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 flame;

[0141] - fiber-reinforced plastics, such as carbon fiber-reinforced plastics (CFK), glass fiber-reinforced plastics (GFK), natural fiber-reinforced plastics (NFK) and sheet molding compounds (SMC);

[0142] - insulating foams, in particular made of EPS, XPS, PUR, PIR, asbestos, glass wool, aerogel or expanded glass (cellular glass);

[0143] - coated or painted substrates, in particular painted tiles, coated concrete, powder-coated metals or alloys or painted sheets;

[0144] - Paint, pigment or lacquer.

[0145] If desired, the substrate can be pretreated before application, in particular by physical and / or chemical cleaning methods or by applying an activator or primer.

[0146] Two identical substrates or two different substrates may be bonded and / or sealed.

[0147] By using the curable composition, an article is obtained. The article is in particular bonded, sealed or coated with the composition. The article may be a building or a part thereof, in particular a building of above-ground or underground construction, a bridge, a roof, a stairwell or a house facade, or an industrial good or a consumer good, in particular a window, a pipe, a rotor blade of a wind power plant, a household machine or a means of transport, such as in particular a car, a bus, a truck, a train, a ship, an airplane or a helicopter or an accessory thereof. Example

[0148] Examples are described below which explain the invention in more detail. The invention is of course not limited to the examples described.

[0149] "Standard climate" ("NK") means a temperature of 23±1° C. and a relative air humidity of 50±5%.

[0150] If not stated otherwise, the chemicals used were from Sigma-Aldrich Chemie GmbH.

[0151] Description of the measurement method:

[0152] The viscosity was measured on a thermostatic cone-plate viscometer Rheotec RC30 (cone diameter 10 mm, cone angle 1°, distance from cone tip to plate 0.05 mm, shear rate 10 s -1 Viscosities less than 1 Pa·s were measured using a 50 mm cone diameter.

[0153] Infrared spectra (FT-IR) were measured in the form of undiluted films on a Thermo Scientific FT-IR instrument Nicolet iS5 equipped with a horizontal ATR-measurement cell with a diamond crystal. The absorption bands are expressed in wavenumbers (cm -1 )express.

[0154] Preparation of polymers containing isocyanate groups:

[0155] Polymer P-1:

[0156] 780g ethylene oxide terminated polyoxypropylene triol ( 5031BT, OH value 28.0 mgKOH / g, OH functionality about 2.3, from Covestro) and 303 g isophorone diisocyanate ( IPDI, from Evonik) was reacted at 80° C. by known methods to form a reaction mixture having an NCO content of 9.1% by weight. Subsequently, 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) to obtain a polymer having an NCO content of 1.84% by weight and a content of monomeric isophorone diisocyanate of 0.02% by weight.

[0157] Polymer P-2:

[0158] 590g polyoxypropylene glycol ( 4200, OH value 28mg KOH / g, from Covestro), 1180g ethylene oxide-terminated polyoxypropylene triol ( MD34-02, OH value 35 mg KOH / g, from Shell) and 230 g isophorone diisocyanate ( IPDI, from Evonik) was reacted at 80° C. by known methods to give a polymer having an NCO content of 2.1% by weight.

[0159] Polymer P-3:

[0160] 725 g ethylene oxide terminated polyoxypropylene triol ( 5031BT, OH value 28.0 mgKOH / g, OH functionality about 2.3, from Covestro) and 275 g of 4,4'-diphenylmethane diisocyanate ( 44MC L, from Covestro) was reacted at 80° C. by a known method to form a reaction mixture having an NCO content of 7.6% by weight. Subsequently, volatile components, in particular unreacted 4,4′-diphenylmethane diisocyanate, were removed by distillation in a short-path evaporator (jacket temperature 180° C., pressure 0.1 to 0.005 mbar, condensation temperature 47° C.) to obtain a polymer having an NCO content of 1.68% by weight and a monomeric 4,4′-diphenylmethane diisocyanate content of 0.04% by weight.

[0161] Polymer P-4:

[0162] 513.3 g polyoxypropylene glycol ( 4200, OH value 28 mg KOH / g, from Covestro), 256.7 g ethylene oxide-terminated polyoxypropylene triol ( MD34-02, OH value 35 mg KOH / g, from Shell) and 64.2 g toluene diisocyanate ( T 80 P from Covestro) was reacted at 80° C. by known methods to give a polymer having an NCO content of 1.5% by weight.

[0163] Polymer P-5:

[0164] 818g polyoxypropylene glycol ( 4200, OH value 28.5 mg KOH / g, from Covestro) and 227 g isophorone diisocyanate ( IPDI, from Evonik) was reacted at 80° C. by known methods to form a reaction mixture having an NCO content of 6.6% by weight. 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) to obtain a polymer having an NCO content of 1.91% by weight and a content of monomeric isophorone diisocyanate of 0.03% by weight.

[0165] Polymer P-6:

[0166] 600g polyoxypropylene glycol ( 1010L, OH value 112 mg KOH / g, from Dow) and 533.3 g isophorone diisocyanate ( IPDI, from Evonik) was reacted at 80° C. by known methods to form a reaction mixture having an NCO content of 15.6% by weight. Subsequently, 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) to obtain a polymer having an NCO content of 5.18% by weight and a monomeric isophorone diisocyanate content of 0.03% by weight.

[0167] Preparation of compounds having two or more aldehyde groups:

[0168] Compounds A-1 to A-7:

[0169] For each compound, the amounts (parts by weight) of the corresponding polymers containing isocyanate groups in Table 1 were reacted with the amounts (parts by weight) of the corresponding hydroxy-functional aldehydes in the presence of 0.02% by weight of dibutyltin dilaurate at 110° C., with exclusion of moisture, until isocyanate groups were no longer detected by means of infrared spectroscopy. For the polymers P-3 and P-4 having aromatic isocyanate groups, the reaction was carried out at 80° C. without dibutyltin dilaurate. A clear, colorless liquid was obtained in each case.

[0170] The properties of compounds A-1 to A-7 are shown in Table 1.

[0171]

[0172]

[0173] Table 1: Preparation and properties of compounds A-1 to A-8.

[0174] 1 4,4'-(2-Hydroxypropane-1,3-diyl)bis(oxy)bis(3-methoxybenzaldehyde), prepared from 2 mol of vanillin and 1 mol of epichlorohydrin. The average molecular weight M of compound A-1 was also determined by gel permeation chromatography (GPC) relative to polystyrene standards (474 ​​to 2520000 g / mol). n , using tetrahydrofuran as the mobile phase and the refractive index detector. The average molecular weight M n It is 6100g / mol.

[0175] Preparation of compounds having two or more cyanoacetate groups:

[0176] Compounds C-1 to C-9:

[0177] For each compound, the corresponding multifunctional alcohol in the specified amount (parts by weight) in Table 2 was mixed with the specified amount (parts by weight) of ethyl cyanoacetate and 0.1 wt % of tetra-n-butyl titanate ( TnBT (from Dorf Ketal) was mixed and reacted at 80 to 140° C. and under reduced pressure to remove volatile components. Except for compound C-9, clear colorless liquids were obtained.

[0178]

[0179] Table 2: Preparation and properties of compounds C-1 to C-9.

[0180] 1 Trimethylolpropane-initiated polyoxypropylene triol ( 4011T, OH value 550mg KOH / g, from Covestro)

[0181] 2 Trimethylolpropane-initiated polyoxypropylene triol ( 1381BT, OH value 385mg KOH / g, from Covestro)

[0182] 3 Polyoxypropylene triol ( 28HS98, OH value 233mg KOH / g, from Covestro)

[0183] 4 Ethoxylated castor oil ( 10, OH value 115 mg KOH / g, from Croda)

[0184] 5 Amorphous polyester diol based on dimerized fatty acid ( 3186, OH value 71mg KOH / g, from Croda)

[0185] 6 Ethylene oxide terminated polyoxypropylene triol ( 5031BT, OH value 28mg KOH / g, from Covestro)

[0186] 7 Dimer fatty acid diol ( 2043, OH value 202 mg KOH / g, from Croda)

[0187] 8 Polyoxypropylene glycol ( P400, OH value 263 mg KOH / g, from Dow)

[0188] Preparation of compounds with acetoacetate groups (comparison):

[0189] Compound R-1:

[0190] To 50g of trimethylolpropane-started polyoxypropylene triol ( 4011T, OH value 550mgKOH / g, from Coves tro) was added with 67g ethyl acetoacetate and 0.12g tetrabutyl titanate ( TnBT, from Dorf Ketal), was reacted at 140° C. and under reduced pressure to remove the volatile components. A clear, colorless liquid was obtained, which had a viscosity of 0.8 Pa·s at 20° C., an average acetoacetate functionality of 3, and an acetoacetate equivalent of 186 g / eq.

[0191] Preparation of curable composition:

[0192] Examples E-1 to E-33

[0193] For each example, the mixture was stirred at room temperature using a centrifugal mixer (SpeedMixer TM DAC 150, FlackTek Inc.) The ingredients of the first component (K1) specified in Tables 3 to 8 were mixed in the specified amounts (parts by weight) and stored in a closed container.

[0194] Likewise, the ingredients of the second component (K2) specified in Tables 3 to 8 are processed and stored.

[0195] Used as "precipitated CaCO3" U1S2 (from Imerys), a precipitated calcium carbonate coated with stearate.

[0196] Used as "carbon black" 570 (from Cabot).

[0197] Subsequently, the two components of each composition were processed using a centrifugal mixer to give a homogeneous paste, which was tested as described below. In the case of E-33 (Ref.), component K2 consisting of compound C-9 was heated to 60° C. or melted before mixing.

[0198] The gel time is determined by stirring a freshly mixed amount of about 3 g with a spatula at regular intervals under standard conditions until the material can no longer be stirred due to gelling.

[0199] To determine the mechanical properties, the mixed compositions were applied to silicone-coated release paper to form a 2 mm thick film, allowed to cure for 7 days in a standard climate, from which several dumbbell-shaped test specimens with a length of 75 mm, a beam length of 30 mm and a beam width of 4 mm were punched out and tested for tensile strength, elongation at break, modulus of elasticity 5% (at 0.5-5% elongation) and modulus of elasticity 50% (at 0.5-50% elongation) at a tensile speed of 200 mm / min in accordance with DIN EN 53504. In addition, some test specimens were punched out for determining the tear propagation strength and tested in accordance with DIN ISO 34-1 method B (angle test specimens) at a tensile speed of 500 mm / min. As a measure of the strength of the adhesive bond, the tensile shear strength of some of the compositions was determined on glass. For this purpose, two panels were degreased with isopropanol and The composites were produced by bonding glass sheets pretreated with Aktivator-205 (from Sika Schweiz) so that the overlapping adhesive joint had a size of 12x25 mm, a thickness of 4 mm, and the top of the glass sheet protruded. After the composites were stored for 7 days in a standard climate, the tensile shear strength was tested according to DIN EN 1465 at a tensile speed of 20 mm / min. Subsequently, the fracture mode was evaluated based on AF (adhesive failure) or CF (cohesive failure). In the absence of other indications, the fracture mode specified in the table was evaluated based on 90% to 100% of the fracture area.

[0200] The Shore A hardness is determined on test specimens cured for 7 days in a standard climate according to DIN 53505. These results are indicated with the designation "7d NK". To determine the heat and water resistance, further Shore A test specimens are cured for 7 days in a standard climate and then stored for a further 7 days in a forced air oven at 100° C. or for a further 7 days at 70° C. and 100% relative humidity and after cooling to room temperature, the Shore A hardness is determined as described above, respectively. These results are indicated with the designation "+7d 100° C." or "+7d 70 / 100".

[0201] During the curing process of the examples of the present invention, non-sticky elastic materials were respectively produced. The examples denoted by "(Ref.)" are comparative examples not of the present invention.

[0202] The results are listed in Tables 3 to 8.

[0203]

[0204]

[0205] Table 3: Composition and properties of E-1 to E-8.

[0206] 1 2,2'-Bis(dimethylamino)diethyl ether

[0207] 2 1,8-diazabicyclo[5.4.0]undec-7-ene( N 700, from BASF)

[0208] Comparison of Example E-1 with Comparative Examples E-7 (Ref.) and E-8 (Ref.) shows that Compound C-1 with cyanoacetate groups is able to achieve mechanical values ​​significantly superior to Compound R-1 with acetoacetate groups, in particular in terms of high tensile strength, high elongation and high tear propagation strength. For Comparative Examples E-7 (Ref.) and E-8 (Ref.), DBU was used as a catalyst to achieve similarly fast gel times.

[0209]

[0210]

[0211] Table 4: Composition and properties of E-1 and E-9 to E-15.

[0212] 1 2,2'-Bis(dimethylamino)diethyl ether

[0213] 2 2,2'-Dimorpholinodiethyl ether

[0214] 3 2,4,6-Tris(dimethylaminomethyl)phenol

[0215] 4 33-LV (from Evonik)

[0216] 5 Potassium acetate, 25 wt% aqueous solution

[0217] "nb" means "not determined"

[0218]

[0219]

[0220] Table 5: Composition and properties of E-10 and E-16 to E-20.

[0221] "nb" means "not determined"

[0222] 1 2,2'-Bis(dimethylamino)diethyl ether

[0223] 2 2,2'-Dimorpholinodiethyl ether

[0224] 3 3-Glycidoxypropyltrimethoxysilane

[0225] 4 3-Mercaptopropyltrimethoxysilane

[0226] 5 75%AF / 25%CF

[0227]

[0228] Table 6: Composition and properties of E-1 and E-21 to E-27.

[0229] "nb" means "not determined"

[0230] 1 2,2'-Bis(dimethylamino)diethyl ether

[0231] 2 2,2'-Dimorpholinodiethyl ether

[0232]

[0233] Table 7: Composition and properties of E-28 to E-30.

[0234] 1Mixture of 1,9-nonanedialdehyde and 2-methyl-1,8-octanedial (NL / MOL, 78.1 g / eq of aldehydes from Kuraray)

[0235] 2 2,2'-Bis(dimethylamino)diethyl ether

[0236] 3 2,2'-Dimorpholinodiethyl ether

[0237] 4 3-Glycidoxypropyltrimethoxysilane

[0238] 5 25%AF / 75%CF

[0239]

[0240]

[0241] Table 8: Composition and properties of E-31 to E-33.

[0242] "nb" means "not determined"

[0243] 1 2,2'-Bis(dimethylamino)diethyl ether

[0244] 2 2,2'-Dimorpholinodiethyl ether

[0245] 3 Not measurable (not properly cured, soft and sticky)

[0246] Examples E-32 (Ref.) and E-33 (Ref.) are comparative examples, in which the first component and the second component have an average functionality of only 2.0 as a compound having an aldehyde group or a compound having a cyanoacetate group, respectively. Such compositions based only on linear reactive compounds cannot be cured to form a solid elastic material, while Example E-31 of the present invention (whose second component has an average cyanoacetate functionality of 3.0) is cured to form an elastic material.

Claims

1. A curable composition comprising - a first component containing an aldehyde group-containing compound, the aldehyde group-containing compound comprising at least one compound having two or more aldehyde groups, and - a second component containing a cyanoacetate group-containing compound, wherein the cyanoacetate group-containing compound comprises at least one compound having two or more cyanoacetate groups, The average molecular weight M of the first component and the second component is calculated as the aldehyde-containing compound or the cyanoacetate-containing compound n In the range of 400 to 20000 g / mol, at least one of the two components has an average functionality of more than 2.0 based on the aldehyde-containing compound or the cyanoacetate-containing compound.

2. The composition according to claim 1, characterized in that Based on the entire composition, less than 10% by weight, preferably less than 5% by weight, in particular less than 2% by weight, of water is contained.

3. The composition according to any one of claims 1 or 2, characterized in that The compound having two or more aldehyde groups is liquid at room temperature.

4. The composition according to any one of claims 1 to 3, characterized in that The average molecular weight M of the first component, calculated as the aldehyde-containing compound, measured by gel permeation chromatography (GPC) relative to a polystyrene standard n In the range of 1000 to 20000 g / mol, preferably 1500 to 15000 g / mol, in particular 2000 to 10000 g / mol.

5. The composition according to any one of claims 1 to 4, characterized in that The aldehyde group-containing compound includes a polymer having a polymer backbone, wherein the polymer backbone contains a poly(oxyalkylene) unit and / or a polyester unit.

6. The composition according to any one of claims 1 to 5, characterized in that Compounds having two or more aldehyde groups also contain a carbamate group.

7. The composition according to any one of claims 1 to 6, characterized in that The aldehyde-containing compound includes a polymer containing a carbamate group which is liquid at room temperature and has an average molecular weight M of n The average aldehyde functionality is 1.8 to 3.5, preferably 2.0 to 3.0, especially 2.2 to 3.

0.

8. The composition according to any one of claims 1 to 7, characterized in that The compounds having two or more aldehyde groups are obtained by reaction of at least one hydroxyaldehyde with at least one isocyanate group-containing polymer or at least one polyisocyanate.

9. The composition according to any one of claims 1 to 8, characterized in that The average functionality of the second component, based on the cyanoacetate group-containing compound, is in the range of 1.6 to 4, preferably 1.8 to 3.5, particularly preferably 2.0 to 3.0, in particular 2.3 to 3.

0.

10. The composition according to any one of claims 1 to 9, characterized in that The average molecular weight M of the second component as a cyanoacetate group-containing compound n In the range of 400 to 10000 g / mol, preferably 500 to 2000 g / mol.

11. The composition according to any one of claims 1 to 10, characterized in that The cyanoacetate group-containing compound comprises at least one cyanoacetate functional polymer selected from the group consisting of n Propoxylated 1,1,1-trimethylolpropane-tri(cyanoacetate) with an average molecular weight of 500 to 2000 g / mol n Poly(oxy-1,2-propylene)diol-bis(cyanoacetate) having an average molecular weight M of 2000 to 10000 g / mol n Poly(oxy-1,2-propylene)triol-tri(cyanoacetate) with an average molecular weight of 2000 to 10000 g / mol n Poly(oxy-1,2-propylene)diol-bis(cyanoacetate) containing ethylene oxide units, with an average molecular weight M of 2000 to 10000 g / mol n Poly(oxy-1,2-propylene)triol-tri(cyanoacetate) containing ethylene oxide units, with an average molecular weight M of 2000 to 10000 g / mol n A polyester diol-di(cyanoacetate) based on dimer fatty acid of 1000 to 4000 g / mol and an average molecular weight M n 1000 to 4000 g / mol of polyester triol-tris(cyanoacetate) based on trimerized fatty acid.

12. The composition according to any one of claims 1 to 11, characterized in that At least one other ingredient is included, and the other ingredient is selected from plasticizers, fillers and catalysts.

13. The composition according to any one of claims 1 to 12, characterized in that Based on the entire composition, less than 10% by weight, preferably less than 5% by weight, in particular less than 1% by weight, of volatile organic solvents having a boiling point of less than 250° C. at standard pressure are contained.

14. A cured composition obtained from the curable composition according to any one of claims 1 to 13 after mixing the two components, wherein the cured composition has in particular a tear propagation strength determined according to DIN ISO 34-1, method B at a tensile speed of 500 mm / min of at least 7 N / mm, in particular at least 10 N / mm.

15. Use of the composition according to any one of claims 1 to 13 as an elastic adhesive, elastic sealant or elastic coating, wherein the first component and the second component and optionally other components are mixed with one another and the mixed composition is applied to at least one substrate in a liquid state.

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