Moisture-curing polyurethane compositions

Abstract

This invention describes a moisture-curing polyurethane composition comprising: – at least one isocyanate-functionalized polymer having a monomeric isophorone diisocyanate content of less than 0.5% by weight, obtained by reacting isophorone diisocyanate with at least one polyol; and – at least one aldolimide of formula (I). This composition exhibits low toxicity, good shelf-life stability, and rapid curing into an elastic material with low surface tack and good mechanical properties, particularly in terms of elastic modulus at high tensile strength and high elongation. It enables coatings, sealants, and adhesives to exhibit excellent stability under outdoor aging conditions and high UV loads. The aldolimide of formula (I) allows overcoming the disadvantages in curing speed, surface tack, and final strength of such compositions caused by the removal of most of the monomeric isophorone diisocyanate. The compositions of this invention are particularly suitable as elastic adhesives and / or sealants or elastic coatings, especially for outdoor applications such as roofing, flooring, or marine applications.

Description

Technical Field

[0001] This invention relates to a moisture-curing polyurethane with a low content of monomeric diisocyanate, particularly for use in coatings, sealants and adhesives with good UV resistance. Existing technology

[0002] Aldehydeimides and their use in moisture-curing polyurethane compositions are well known. Aldehydeimides are used as so-called latent curing agents or blocked amines. They react with isocyanate groups upon contact with moisture and improve the curing properties of moisture-curing polyurethane compositions, particularly by preventing bubble formation caused by excessive release of carbon dioxide during the reaction of water with isocyanate groups. Aldehydeimides that are liquid at room temperature are particularly suitable because they can be readily handled without solvents.

[0003] In outdoor coatings, sealants, and adhesives, moisture-curing polyurethane compositions typically contain isocyanate-functionalized polymers based on aliphatic diisocyanates, particularly alicyclic isophorone diisocyanates, because these offer particularly good UV resistance. When combined with latent curing agents, such compositions cure rapidly to form an elastic material. However, they often remain slightly tacky at the surface and / or have limited mechanical properties in terms of tensile strength and modulus of elasticity, making them susceptible to dust accumulation and / or degradation under outdoor climatic conditions such as water accumulation and UV exposure. These effects are particularly pronounced in compositions with relatively low isocyanate content, such as low-modulus sealants and adhesives, or coatings based on polymers with reduced monomer content. Monomer isophorone diisocyanates, like other small isocyanates, are toxic and volatile molecules that pose potential health risks to applicators. Therefore, from an EH&S perspective, it is advantageous to remove them from isocyanate-functionalized polymers, for example, by distillation.

[0004] Compositions containing less than 0.5% by weight, and especially less than 0.1% by weight, of the monomeric isophorone diisocyanate tend to remain tacky for extended periods after curing and are limited in achievable mechanical strength, and therefore in terms of durability under weathering conditions. These negative effects can be mitigated by adding increased amounts of isocyanate crosslinking agents (e.g., oligomers of isophorone diisocyanate), but this results in undesirable hardening of the cured composition and a loss of elongation.

[0005] WO 2020 / 030607 describes the use of blocked amines as auxiliary curing agents for moisture-curing polyurethane compositions having very low contents of the monomer isophorone diisocyanate. These compositions are cured to form elastic materials with high elongation by using well-known blocked amines, such as aldehyde imides derived from isophorone diamine and 2,2-dimethyl-3-(N-morpholino)propionaldehyde. However, the mechanical properties, particularly the elastic modulus, do not reach the levels of conventional compositions with high contents of the monomer isophorone diisocyanate.

[0006] EP 2,132,247 discloses a dialdehyde imine derived from solid bis(4-aminocyclohexyl)methane and 2,2-dimethyl-3-lauroyloxypropionaldehyde, and its use in polymers with conventional (non-monomer-reduced) isophorone diisocyanate groups. This aldehyde has a strong plasticizing effect on polyurethane polymers, which further reduces the achievable levels of mechanical strength in compositions with very low monomer isophorone diisocyanate content. Invention Overview

[0008] The objective of this invention is to provide a moisture-curing polyurethane composition with low toxicity and good UV resistance, which overcomes the shortcomings of prior art compositions, particularly in terms of surface tack and limited mechanical strength.

[0009] Surprisingly, this task is achieved through a moisture-curable polyurethane composition comprising a low content of the monomer isophorone diisocyanate and an aldehyde imine according to formula (I) of claim 1. The compositions of the present invention provide isophorone diisocyanate-based moisture-curable polyurethanes with a monomer isophorone diisocyanate content of less than 0.1% by weight, which form an elastic material with low surface tack and significant mechanical strength without the disadvantages of viscosity, shelf-life stability, or elongation at break. Such compositions are particularly suitable for applications exposed to outdoor climatic conditions, such as elastic coatings for outdoor floors or roofs, or elastic adhesives or sealants for applications with heavy UV loads, such as joint sealants for high-rise facades or deck sealants for ships and boats.

[0010] The compositions of this invention exhibit good shelf-life stability and low viscosity. They are easy to apply and have sufficient open time to allow for precise positioning and application over large surfaces. However, the curing process is rapid, causing the composition to quickly become substantially non-sticky and exhibit rapid build-up of mechanical strength and elasticity. The cured material exhibits high mechanical strength at high elasticity, particularly a high modulus of elasticity at high tensile strength, tear strength, and elongation, as well as high durability under outdoor climatic conditions, primarily in terms of stability to water and UV light.

[0011] Particularly preferred are the compositions of the invention in which the aldehyde imine of formula (I) is present as a mixture of isomers containing low amounts of the trans, trans-isomers. These are particularly easy to handle, require no melting step or use of solvents, and surprisingly provide optimal mechanical properties in terms of tensile strength and / or modulus of elasticity.

[0012] Other aspects of the invention are described in the other independent claims. Preferred aspects of the invention are described in the dependent claims. Invention Details

[0014] The subject of this invention is a moisture-curing polyurethane composition comprising:

[0015] – A polymer with at least one isocyanate functional, wherein the monomer isophorone diisocyanate comprises less than 0.5% by weight, obtained by reacting isophorone diisocyanate with at least one polyol, and

[0016] – At least one aldehyde imine of formula (I),

[0017]

[0018] in

[0019] R 1 and R 2 They are either hydrogen or methyl, which are independent of each other.

[0020] R 3 and R 4 They are the same or different C1 to C4 alkyl groups, or linked together to form C4 to C6 alkylene groups, and

[0021] R 5 and R 6 They are the same or different C1 to C8 alkyl groups optionally containing ether oxygen, or linked together to form C4 to C6 alkylene groups optionally containing ether oxygen.

[0022] In this document, the term "wet-curing" refers to a composition that cures when exposed to moisture.

[0023] In this document, the terms “shelf life stability” and “storage stability” refer to the ability of a composition to be stored at room temperature in a suitable container, excluding moisture, for a period of time (particularly several months) without experiencing significant changes in its properties for application or end use.

[0024] In this paper, the term "molecular weight" refers to the molar mass (g / mol) of a molecule or molecular moiety. The term "average molecular weight" refers to the number-average molecular weight (Mn) of an oligomer or polymer mixture of molecules or molecular moiety. It is determined by gel permeation chromatography (GPC) using polystyrene as a standard, specifically tetrahydrofuran as the mobile phase and refractive index detector.

[0025] In this document, the term "NCO content" refers to the content of isocyanate groups in weight percent.

[0026] In this document, unless otherwise stated, the term "weight%" refers to the mass fraction of the composition components based on the whole composition. The terms "weight" and "mass" are used synonymously herein.

[0027] In this article, "room temperature" refers to a temperature of 23°C.

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

[0029] Preferably, it is an aldimine of formula (I) that is liquid at 23°C. This aldimine is particularly a mixture of isomers of formula (I) having low contents of trans, trans-isomers, as described below.

[0030] Preferably, R 1 and R 2 All are hydrogen or all are methyl.

[0031] Most preferably, R 1 and R 2 Both are hydrogen.

[0032] Further preferred are aldehyde imines of formula (I), wherein R 3 and R 4 All are methyl groups.

[0033] Further preferred are aldehyde imines of formula (I), wherein R 5 and R 6 All are methoxyethyl, or linked together to form 3-oxa-1,5-pentylene or 2,4-dimethyl-3-oxa-1,5-pentylene, which are related to R 5 and R 6 The bonded nitrogen atoms together form a morpholine or 2,6-dimethylmorpholine ring.

[0034] Preferably, R 5 and R 6 They connect together to form 3-oxa-1,5-pentylene, which is part of the morpholine ring.

[0035] Particularly preferred are aldehyde imines of formula (I), wherein R 3 and R4 Both are methyl groups, R 5 and R 6 They are linked together to form 3-oxa-1,5-pentylene, which is part of the morpholine ring. This aldehyde imine of formula (I) is readily available and exhibits particularly good shelf-life stability when stored in a sealed container with the isocyanate group.

[0036] The aldehyde imine of formula (I) is preferably used in the form of a mixture of isomers. Since the two substituents of each cyclohexyl ring can be trans or cis, there are three possible isomers: trans,trans-isomer, cis,trans-isomer, and cis,cis-isomer, as shown in the following formula:

[0037]

[0038] The isomer composition depends on the starting amine used to prepare the aldehyde imine of formula (I). For the aldehyde imine of formula (I), where R 1 and R 2 Both are hydrogen, R 3 and R 4 Both are methyl groups, R 5 and R 6 When linked together, they form a mixture of 3-oxa-1,5-pentyl isomers. A mixture containing approximately 20% trans and trans-isomers is liquid at room temperature, while a mixture containing 50% or more trans and trans-isomers is solid at room temperature. After melting, this mixture will harden again within hours to days of storage at room temperature.

[0039] Particularly preferred are the aldehyde imines of formula (I), which are mixtures containing less than 35%, preferably less than 30%, more preferably up to 25% of the trans-trans isomers of the isoform aldehyde imines.

[0040] Particularly preferred are aldehyde imines of formula (I), wherein R 1 and R 2 Both are hydrogen, R 3 and R 4 Both are methyl groups, R 5 and R 6 Together they are 3-oxa-1,5-pentylene, which, with R 5 and R 6 The bonded nitrogen atoms together form a morpholine ring. This aldehyde imine is N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-4,4'-methylene-bis(cyclohexylamine).

[0041] Particularly preferred are the aldehyde imine of formula (I), which is a mixture containing less than 35%, preferably less than 30%, more preferably up to 25% of the trans-trans isomer of N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-4,4'-methylene-bis(cyclohexylamine).

[0042] The most preferred is a mixture containing 15-25% of the trans-trans isomer of the isomer N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-4,4'-methylene-bis(cyclohexylamine).

[0043] Surprisingly, the aldehyde imide of formula (I) is able to compensate for most of the mechanical property loss caused by the lack of isophorone diisocyanate monomer in IPDI-based polyurethanes due to monomer reduction, a degree unattainable by other known aldehyde imides and alicyclic aldehyde imides. The beneficial effect on mechanical properties is particularly pronounced when the aldehyde imide of formula (I) is used in the form of a preferred mixture of isomers with a trans,trans-isomer content of less than 35%. As expected, the trans,trans-isomer, due to its strong segment stacking, symmetry, and geometric stretching, provides better mechanical properties than the asymmetric cis,cis, and cis,trans isomers.

[0044] The aldehyde imine of formula (I) is preferably prepared in a condensation reaction between at least one amine of formula (II) and at least one aldehyde of formula (III).

[0045]

[0046] In equations (II) and (III), R 1 To R 6 It has the meaning already mentioned.

[0047] The stoichiometric ratio between the aldehyde of formula (III) and the amine of formula (II) is preferably at least 1 in order to convert all amine groups.

[0048] The condensation reaction is preferably carried out at a temperature of 15-120°C, more preferably 20-100°C. The water released by the condensation reaction is preferably removed from the reaction product, for example as an azeotrope with a suitable solvent, or preferably removed by distillation in the absence of a solvent.

[0049] The condensation reaction is preferably carried out in the absence of a solvent, and water is removed from the reaction product by vacuum distillation. This reaction product can be used as the aldehyde imine of formula (I) without further purification.

[0050] The preferred amine of formula (II) is 4,4'-methylene-bis(cyclohexylamine) or 4,4'-isopropylidene-bis(cyclohexylamine), especially 4,4'-methylene-bis(cyclohexylamine).

[0051] Particularly preferred is the 4,4'-methylene-bis(cyclohexylamine) grade, which is liquid at room temperature and contains less than 35%, preferably less than 30%, and especially up to 25% of the trans,trans-isomer. Suitable liquid grades with trans,trans-isomer content in the range of 15% to 25% are commercially available, for example as... PACM or PACM (from Evonik) or H 12 MDA (from Wanhua Chem.). They are superior to solid grades containing more than 35%, particularly about 50%, of the trans, trans-isomer of 4,4'-methylene-bis(cyclohexylamine), for example, as Those available for commercial purchase (from BASF).

[0052] The preferred aldehyde of formula (III) is 2,2-dimethyl-3-di(methoxyethyl)aminopropionaldehyde, 2,2-dimethyl-3-(N-2,6-dimethylmorpholino)propionaldehyde or 2,2-dimethyl-3-(N-morpholino)propionaldehyde, especially 2,2-dimethyl-3-(N-morpholino)propionaldehyde.

[0053] Aldehydes of formula (I) may contain small amounts of aldehydes of formula (IV).

[0054]

[0055] Where R 1 To R 6 It has the meaning already mentioned.

[0056] The aldehyde imine of formula (I) may also contain the corresponding 2,4'- and / or 2,2'- isomers, particularly the 2,4'- isomer of formula (IVa).

[0057]

[0058] Where R 1 To R 6 It has the meaning already mentioned.

[0059] Preferably, the ratio of the sum of the 2,4'- and 2,2'- isomers to the aldehyde imine of formula (I) (i.e., the 4,4'- isomer) is less than 20 / 80, and particularly not greater than 10 / 90. In a preferred embodiment, it is in the range of 0 / 100 to 2 / 98. In another particularly preferred embodiment, it is in the range of 5 / 95 to 10 / 90.

[0060] The aldehyde imine of formula (I) may also contain the aldehyde imine moiety of formula (IVb) and / or (IVc).

[0061]

[0062] Where R 1 To R 6 It has the meaning already mentioned.

[0063] Preferably, the weight ratio of the sum of the aldolimides of formulas (IVb) and (IVc) to the aldolimide of formula (I) is less than 30 / 70.

[0064] The moisture-curing polyurethane composition comprises at least one isocyanate-functionalized polymer, wherein the monomer isophorone diisocyanate is present in a content of less than 0.5% by weight, and is obtained by the reaction of isophorone diisocyanate and at least one polyol.

[0065] The isocyanate-functionalized polymer preferably contains less than 0.3% by weight of isophorone diisocyanate monomer, more preferably less than 0.2% by weight. This isocyanate-functionalized polymer enables compositions with a total content of less than 0.1% by weight of monomer diisocyanate monomer, which allows the applicator to be used safely without special protective measures and hazard markings.

[0066] Isocyanate-functionalized polymers are preferably liquids at room temperature.

[0067] Preferably, the polymer is a low-viscosity isocyanate-functionalized polymer, preferably having a viscosity of less than 50 Pa·s, more preferably less than 30 Pa·s, and particularly less than 20 Pa·s, passing through a cone with a diameter of 25 mm, a cone angle of 1°, a cone-plate distance of 0.05 mm, and a shear rate of 10 s. -1 The cone-plate viscometer was used for measurement at 20°C.

[0068] The isocyanate-functionalized polymer preferably has an NCO content of 1 to 8% by weight, more preferably 1.5 to 6% by weight.

[0069] The average molecular weight M of isocyanate-functionalized polymers n Preferably, the concentration is 1000 g / mol to 15000 g / mol, more preferably 1500 g / mol to 12000 g / mol.

[0070] The isocyanate-functionalized polymer is obtained by reacting isophorone diisocyanate with at least one polyol.

[0071] Preferably, the reaction is carried out at an NCO / OH molar ratio of at least 3 / 1, preferably in the range of 3 / 1 to 10 / 1, and then most of the remaining monomeric isophorone diisocyanate is removed by a distillation process.

[0072] The polyols are preferably selected from polyether polyols, polyester polyols, polycarbonate polyols and polyacrylate polyols.

[0073] Preferred are polyether polyols, preferably having repeating units selected from 1,2-ethyleneoxy, 1,2-propyloxy, 1,3-propyloxy, 1,2-butyloxy, and 1,4-butyloxy. Particularly preferred are 1,2-propyloxy units, optionally combined with some 1,2-ethyleneoxy units at the chain ends. Further particularly preferred are 1,4-butyloxy units.

[0074] Preferred polyether polyols have an unsaturation content of less than 0.02 meq / g, and more preferably less than 0.01 meq / g.

[0075] Preferred are polyoxypropylene glycol or triol, optionally ethylene oxide-terminated, and have an OH value in the range of 10 to 250 mg KOH / g, preferably 20 to 125 mg KOH / g.

[0076] The average OH-functionality of the polyol is preferably in the range of 1.7 to 3.

[0077] Particularly preferred are polyoxypropylene glycols, optionally ethylene oxide-terminated, with an average molecular weight M n The concentration is in the range of 450 to 12000 g / mol, preferably in the range of 1000 g / mol to 6000 g / mol.

[0078] Particularly preferred are polyoxypropylene triols starting with trimethylolpropane or glycerol, optionally ethylene oxide-terminated, with an average molecular weight M n Within the range of 3000 to 8000 g / mol.

[0079] Particularly preferred are poly(oxy-1,4-butylene) glycols, especially those with an OH value in the range of 50 to 180 mg KOH / g, and particularly those with an average molecular weight M. n In the range of 650 to 2000 g / mol.

[0080] The NCO / OH molar ratio during the reaction between isophorone diisocyanate and polyol is preferably in the range of 3 / 1 to 10 / 1, more preferably in the range of 3 / 1 to 8 / 1.

[0081] The reaction between isophorone diisocyanate and polyol is preferably carried out in the absence of water, at a temperature of 20-160°C, preferably 40-140°C, and, where possible, in the presence of a suitable catalyst.

[0082] After the reaction, the remaining monomeric isophorone diisocyanate is removed from the reaction mixture by distillation, preferably by thin-film distillation or short-path distillation, preferably under vacuum.

[0083] A particularly preferred method is a multi-step process in which the monomer isophorone diisocyanate is removed in a short-path evaporator at a jacket temperature of 120-200°C, preferably 140-180°C, and a pressure of 0.001-0.5 mbar.

[0084] Preferably, the reaction between isophorone diisocyanate and polyol, as well as the removal of residual monomeric diisocyanate, are carried out in the absence of solvents or entrainers.

[0085] Preferred is an isocyanate-functionalized polymer having a monomer isophorone diisocyanate content of less than 0.3% by weight and an NCO content of 1-10% by weight, which is obtained by reacting isophorone diisocyanate with at least one polyether polyol with an OH value of 10-250 mg KOH / g at an NCO / OH molar ratio of 3 / 1-10 / 1, and then removing most of the monomer isophorone diisocyanate by a distillation process.

[0086] Particularly preferred isocyanate-functionalized polymers have an NCO content of 5-6% by weight and an OH value of 110-115 mg KOH / g and an average molecular weight M. n It is obtained from approximately 1000 g / mol of polyoxypropylene glycol. It is particularly suitable for elastic coatings.

[0087] Another particularly preferred isocyanate-functionalized polymer has an NCO content of 1.7-2% by weight and is composed of an OH value of 26-30 mg KOH / g and an average molecular weight M. n It is obtained from approximately 4000 g / mol of polyoxypropylene glycol. It is particularly suitable for elastic adhesives, sealants, or coatings.

[0088] Another particularly preferred isocyanate-functionalized polymer has an NCO content in the range of 1.7 to 2.5% by weight, and an OH value in the range of 26 to 37 mg KOH / g and an average molecular weight M n Polyoxypropylene triols, possibly ethylene oxide-terminated, are obtained in the range of 4500 to 6000 g / mol. They are particularly suitable for elastic adhesives or sealants.

[0089] Another particularly preferred isocyanate-functionalized polymer has an NCO content of 2.8-7.7% by weight and is obtained from poly(oxy-1,4-butylene) glycol with an OH value of 55-175 mg KOH / g. It is particularly suitable for elastic coatings with exceptionally high UV and water resistance.

[0090] The composition may contain one or more of these isocyanate-functionalized polymers.

[0091] The polyurethane composition of the present invention preferably contains less than 0.1% by weight of a monomeric diisocyanate relative to the total composition. This composition allows for safe use of the application device without the need for special protective measures and hazard markings.

[0092] Preferably, the polyurethane composition contains at least one latent curing agent selected from aldehydes and imides other than those of formula (I), oligomeric polyisocyanates, fillers, plasticizers, catalysts, and other components such as stabilizers.

[0093] Preferred latent curing agents of this type are oxazolidine, bisoxazolidine, or aldicarmines other than those of formula (I).

[0094] The preferred aldehyde imine, which differs from that of formula (I), is the aldehyde imine of formula (V).

[0095]

[0096] in

[0097] n is 2 or 3

[0098] A is a residue of a diamine or triamine after the amino group has been removed, wherein the diamine or triamine is selected from hexane-1,6-diamine, 2-methylpentane-1,5-diamine, 3-aminomethyl-3,5,5-trimethylcyclohexylamine (isophorone diamine), 4(2)-methylcyclohexane-1,3-diamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-bis(aminomethyl)benzene, 1,2-diaminocyclohexane, and the average molecular weight M is... n Polyoxypropylene diamine in the range of 200 to 4000 g / mol and average molecular weight M n Polyoxypropylene triamine in the range of 380 to 5000 g / mol, and

[0099] R 3 To R 6 It has the meaning already mentioned.

[0100] Preferably, R 3 R 4 R 5 and R 6 The same group is present in formulas (I) and (V). This means that the aldimine of formula (I) and the aldimine of formula (V) are derived from the same aldehyde.

[0101] The polyurethane composition preferably contains at least one aldehyde imine of the formula (Va).

[0102]

[0103] Where R 3 To R 6It has the meaning already mentioned. This aldehyde imine is obtained from isophorone diamine and enables the realization of particularly cost-effective compositions with low viscosity and good mechanical properties.

[0104] Preferably, the weight ratio between the aldehyde imide of formula (I) and the aldehyde imide of formula (Va) is 10 / 90-80 / 20, more preferably 20 / 80-75 / 25, more preferably 30 / 70-70 / 30, and most preferably 40 / 60-60 / 40. Within this ratio range, compared with the aldehyde imide of formula (Va) alone, the composition surprisingly exhibits a faster curing speed and / or improved mechanical strength and / or a less tacky surface.

[0105] The polyurethane composition preferably further contains at least one aldehyde imine of the formula (Vb).

[0106]

[0107] Where T is the value when the average molecular weight M is removed. n The remaining trifunctional moiety of the primary amino group of polyoxypropylene triamine in the range of 380 to 500 g / mol, said polyoxypropylene triamine can, for example, be used as... T-403 (obtained commercially from Huntsman), and R 3 To R 6 It has the meaning already mentioned.

[0108] Preferably, the weight ratio between the aldehyde imine of formula (I) and the aldehyde imine of formula (Vb) is 30 / 70-80 / 20, more preferably 40 / 60-70 / 30.

[0109] In a particularly preferred embodiment of the invention, the composition contains at least one aldimine of formula (Va) and at least one aldimine of formula (Vb). Preferably, the weight ratio between the aldimines of formula (I), (Va), and (Vb) is 15-45 / 20-50 / 20-50, wherein the sum of the three numbers equals 100.

[0110] Other preferred aldehyde imines different from those of formula (I) are those of formula (VI).

[0111]

[0112] Where R 1 and R 2 It has the meaning already mentioned, and

[0113] Y is a monovalent C3 to C4 group that optionally contains ether and / or ester groups. 20 Hydrocarbon group.

[0114] This combination allows for specific customization of curing behavior, particularly in terms of open time and curing speed.

[0115] Preferably, Y is a branched C3 to C7 alkyl group, particularly isopropyl, or a phenyl or substituted phenyl group, particularly phenyl or C7 alkyl. 10 To C 14 Alkyl-substituted phenyl groups, or ester-containing alkyl groups, especially 2,2-dimethyl-2-acetoxyethyl or 2,2-dimethyl-2-lauroyloxyethyl.

[0116] Preferably, the weight ratio of the aldimine of formula (VI) to the aldimine of formula (I) is less than 20 / 80.

[0117] In a particularly preferred embodiment, Y is isopropyl, and the weight ratio of the aldolimide of formula (VI) to the aldolimide of formula (I) is 1 / 99 to 3 / 97.

[0118] The polyurethane composition preferably also contains oligomers of isophorone diisocyanate, particularly isocyanurate of isophorone diisocyanate. Such oligomeric polyisocyanates can contribute to achieving high strength. However, their use is somewhat limited because when used in excessive amounts, they can cause a significant increase in stiffness while elongation decreases to complete brittleness. Therefore, the loss of mechanical strength due to the removal of most of the monomeric isophorone diisocyanate cannot be compensated for by adding oligomeric polyisocyanates.

[0119] Suitable fillers are ground or precipitated calcium carbonate (chalk), optionally coated with fatty acids such as stearates, barium sulfate (barite), slate, silicates (quartz), magnesium silicates (talc) or aluminosilicates (clay, kaolin), dolomite, mica, glass bulbs, silicic acid, especially highly dispersed silicic acid (fumed silica) from pyrolysis processes, carbon black, microspheres, pigments, especially titanium dioxide or iron oxide, or flame-retardant fillers such as aluminum hydroxide, especially aluminum trihydride (ATH), magnesium hydroxide, antimony trioxide, antimony pentoxide, boric acid, zinc borate, zinc phosphate, melamine borate, melamine cyanurate, ethylenediamine phosphate, ammonium polyphosphate, bis(melamine) orthophosphate, bis(melamine) pyrophosphate, hexabromocyclododecane, decabromodiphenyl ether, and tri(bromoneoptiyl) phosphate.

[0120] Preferred fillers are chalk, barite, pyrolytic silica and / or ATH.

[0121] Suitable plasticizers are phthalates, especially diisononyl phthalate (DINP) or diisodecyl phthalate (DIDP), hydrogenated phthalates, especially hydrogenated DINP, which is diisononyl 1,2-cyclohexanedicarboxylate (DINCH), terephthalates, especially bis(2-ethylhexyl) terephthalate or diisononyl terephthalate, hydrogenated terephthalates, especially bis(2-ethylhexyl) 1,4-cyclohexanedicarboxylate, trimellitates, adipates, especially dioctyl adipate (DOA), azelaic acid esters, sebacic acid esters, citrates, benzoates, glycol ethers, glycol esters, organic sulfonates or phosphate esters, especially diphenyltoluene phosphate (DPK), polybutene, polyisobutylene, or plasticizers obtained from natural fats or oils such as epoxidized soybean oil or linseed oil.

[0122] Suitable catalysts for promoting the hydrolysis of aldimines are acid catalysts, especially carboxylic acids or sulfonic acids, preferably aromatic carboxylic acids, such as benzoic acid or salicylic acid.

[0123] Suitable catalysts are those used to promote the reaction of isocyanate groups, particularly metal catalysts, preferably dialkyltin complexes, especially dibutyltin or dioctyltin carboxylates or acetylacetonates, such as dibutyltin dilaurate (DBTDL), di(acetoacetic acid) dibutyltin (DBT(acac)2) or dioctyltin dilaurate (DOTDL), or amine catalysts, preferably tertiary amino ethers, especially 2,2'-dimorpholinodiethyl ether (DMDEE).

[0124] Preferred stabilizers are UV stabilizers and / or heat stabilizers, particularly UV absorbers such as ethyl 2-cyano-3,3-diphenylacrylate, or hindered amine light stabilizers (HALS), such as bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate.

[0125] The polyurethane composition may further contain the following components:

[0126] – Other isocyanate-functionalized polyurethane polymers;

[0127] – Compounds with isocyanate functionality derived from small molecule diols such as 1,2-ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, neopentanediol or diethylene glycol, especially isocyanate-functionalized compounds obtained from 1,4-butanediol.

[0128] - Organic solvents, especially acetone, methyl ethyl ketone, methyl n-propyl ketone, diisobutyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, methyl isopentyl ketone, acetylacetone, mesitylene ether, cyclohexanone, methyl cyclohexanone, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, tert-butyl acetate, 1-methoxy-2-propyl acetate, n-butyl propionate, ethyl-3-ethoxypropionate, diethyl malonate, diisopropyl ether, dibutyl ether, ethylene glycol diethyl ether, ethylene glycol monopropyl ether, ethylene glycol mono-2-ethylhexyl ether, diethylene glycol diethyl ether, propionaldehyde, butyraldehyde, 2-ethylhexanal, dioxolane, glyceryl formaldehyde, 2,5,7,10-tetraoxaundecane (TOU), toluene, xylene, heptane, octane, diisopropylnaphthalene, petroleum fractions such as naphtha, petroleum solvents or petroleum ethers such as Solvesso. TM Solvents (from Exxon), hydrogenated naphtha, dichloromethane, propylene carbonate, dimethyl carbonate, butyrolactone, N-methylpyrrolidone, N-ethylpyrrolidone, p-chlorotrifluorotoluene or trifluorotoluene;

[0129] - Fibers, especially glass fiber, carbon fiber, metal fiber, ceramic fiber, plastic fiber, especially polyamide fiber or polyethylene fiber, or natural fibers such as wool, cellulose, hemp or sisal.

[0130] - Nanofillers, such as graphene or carbon nanotubes;

[0131] -dye;

[0132] -Desiccants, especially molecular sieves, calcium oxide, highly reactive isocyanates such as p-toluenesulfonyl isocyanate, and monooxazolidines such as... 2 (from Incorez) or orthoformate;

[0133] - Adhesion promoters, particularly organoalkoxysilanes, such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (meth)acryloylsilane, anhydride silane, carbamate silane, alkylsilane or iminosilane, or oligomers thereof, or titanates.

[0134] -Thickeners, such as bentonite, castor oil derivatives, hydrogenated castor oil, polyamide, polyamide wax, polyurethane, urea compounds, pyrolytic silica, cellulose ethers, or hydrophobically modified polyoxyethylene.

[0135] - Natural resins, fats or oils, such as rosin, shellac, linseed oil, castor oil or soybean oil;

[0136] - Non-reactive polymers, especially homopolymers or copolymers of unsaturated monomers (especially ethylene, propylene, butene, isobutylene, isoprene, vinyl acetate or (meth)acrylate), preferably polyethylene (PE), polypropylene (PP), polyisobutylene, ethylene vinyl acetate copolymer (EVA) or atactic polyalphaolefin (APAO).

[0137] – Additives, such as wetting agents, flow enhancers, leveling agents, defoamers, degassing agents, stabilizers, antioxidants, or biocides.

[0138] The composition preferably contains 15 to 80% by weight, particularly 20 to 50% by weight, of an isocyanate-functionalized polymer relative to the total composition.

[0139] The composition preferably contains 0.5 to 25% by weight, preferably 1 to 20% by weight, of an aldehyde imine of formula (I) relative to the total composition.

[0140] The composition preferably contains a certain amount of aldimine, such that the ratio between the total number of aldimine groups and the total number of isocyanate groups is in the range of 0.3 to 1, preferably 0.4 to 1, more preferably 0.5 to 1.

[0141] The composition preferably contains 0 to 10% by weight, preferably 0.1 to 5% by weight, of an oligomer of isophorone diisocyanate relative to the total composition.

[0142] The composition preferably contains 0 to 40% by weight, more preferably 10 to 30% by weight, of plasticizer relative to the total composition.

[0143] The composition preferably contains 0 to 80% by weight, preferably 20 to 60% by weight, of filler relative to the total composition.

[0144] In a preferred embodiment of the invention, the composition further comprises at least one flame-retardant component, preferably a flame-retardant filler and / or a flame-retardant plasticizer. This composition is particularly preferred as a waterproof coating for buildings, especially roofs.

[0145] The preferred flame-retardant filler is aluminum trioxide (ATH). The preferred flame-retardant plasticizer is diphenyltoluene phosphate (DPK).

[0146] A particularly preferred composition contains at least one aluminum trioxide filler. This composition is particularly preferred as a waterproof coating for buildings. Preferably, it also contains at least one oligomer of isophorone diisocyanate.

[0147] The composition preferably contains a small amount of a volatile organic solvent with a boiling point below 200°C at atmospheric pressure. Preferably, each liter of the total composition contains no more than 200 grams of such volatile organic solvent, more preferably no more than 150 grams. This composition is particularly suitable as a waterproof coating for buildings.

[0148] For other uses, such as adhesives or bonding fillers, the composition preferably contains even less than 10% by weight, more preferably less than 5% by weight, and most preferably less than 1% by weight, relative to the total composition.

[0149] Moisture-curing polyurethane compositions are preferably formulated as single-package compositions, prepared by mixing all components while removing moisture to obtain a macroscopically homogeneous fluid or paste, and storing it in a moisture-proof container at ambient temperature. Suitable moisture-proof containers are preferably made of optionally coated metal or plastic. They are preferably buckets, tubes, jugs, bags, sausage bags, tins, cans, bottles, or tubes. Under suitable packaging and storage, single-package moisture-curing polyurethane compositions exhibit good shelf-life stability.

[0150] The curing process begins when the moisture-curing composition is applied and comes into contact with moisture, particularly atmospheric moisture. During curing, isocyanate groups react with hydrolyzed aldehyde-imine groups under the influence of moisture. Additional isocyanate groups, especially those in excess relative to the aldehyde-imine groups, react with each other under the influence of moisture. As a result of these reactions, the composition cures to form an elastic material. During the curing reaction, an aldehyde of formula (III) is released. This aldehyde has a very low odor and is partially retained in the cured composition, where it is well compatible with the polymer and does not show a significant tendency to migrate.

[0151] Another subject of the present invention is a cured composition obtained from a moisture-curing polyurethane composition upon contact with moisture.

[0152] The moisture used for curing the composition is preferably atmospheric moisture that diffuses into the composition from the surrounding air via a diffusion process. During curing, a thin skin of the cured composition is initially formed on the surface of the applied composition, the thickness of which continuously increases as the curing process continues until all the applied composition is cured. Additional moisture contributing to the curing process can originate from the substrate on which the composition is applied, and / or from an accelerator component containing or releasing water, which is incorporated into the composition before or during application, or sprayed or brushed onto the surface of the applied composition.

[0153] The moisture-curing polyurethane composition is preferably applied under ambient conditions, preferably at a temperature range of -10 to 50°C, more preferably -5 to 45°C, and particularly 0 to 40°C.

[0154] The curing of the composition is preferably carried out under environmental conditions.

[0155] The moisture-curing polyurethane composition has sufficient open time to allow for precise positioning and large surface application, as well as a rapid curing process, thereby the composition quickly becomes non-sticky and exhibits rapid establishment of mechanical strength and elasticity.

[0156] "Open time" refers to the time during which the applied composition can be processed or reprocessed without any negative impact. This time ends when the viscosity of the composition increases too much due to curing, at the latest when a skin forms on the surface. The period of time until a skin forms on the surface is called "skin formation time" or "skinning time".

[0157] Moisture-curing polyurethane compositions are preferably used as elastic adhesives and / or sealants or as elastic coatings.

[0158] As an elastic adhesive and / or sealant, this composition is particularly suitable for building or manufacturing industrial or vehicle construction, especially for splicing floor bonding, assembly or module bonding, or as a joint or cavity sealant and filler, such as for high-rise facades or ship decks exposed to particularly high UV loads.

[0159] As an elastic coating, this composition is particularly suitable for sealing and protecting buildings or parts thereof, such as bridges, balconies, terraces, roofs, especially flat or slightly sloping roofs, roof gardens, or the interior of buildings under tiles in wet spaces or kitchens, or in storage tanks, passageways, shafts, silos, tanks or wastewater treatment plants.

[0160] It can also be used for repair purposes, especially on damaged roofing membranes, floor coverings, or sprayed films.

[0161] Moisture-curing polyurethane compositions can be formulated in such a way that they have a paste-like consistency with pseudoplastic properties. Such compositions are preferably applied from a canister, drum, or bucket, for example, in the form of adhesive strips having circular or triangular cross-sectional areas.

[0162] The moisture-curing polyurethane composition can be further formulated to have a self-leveling fluid consistency, optionally with slight thixotropy. Such a composition can be applied by spraying or pouring onto a flat or slightly inclined surface. To form a uniform coating, the composition can then optionally be spread to the desired layer thickness using a suitable tool such as a scraper, toothed trowel, doctor blade, roller, brush, or applicator stick. Typically, a layer thickness of 0.5–3 mm, preferably 0.5–2 mm, is applied in a single step.

[0163] Suitable substrates on which the composition is typically applied, especially

[0164] - Concrete, lightweight concrete, mortar, cement, fiber cement, brick, adobe, tile, slate, gypsum, gypsum board, or natural stone such as granite or marble;

[0165] - Glass or glass-ceramic;

[0166] - Repair or leveling compounds based on PCC (polymer-modified cement) or ECC (epoxy-modified cement);

[0167] - Metals and alloys, such as aluminum, copper, iron, steel, and non-ferrous metals, including surface-finished metals and alloys, such as galvanized or chromium-plated metals.

[0168] -asphalt;

[0169] –asphalt felt;

[0170] - Plastics, such as rigid or flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resin, phenolic resin, PUR, POM, TPO, PE, PP, EPM or EPDM, which are in untreated form or have been surface-treated by plasma, corona or flame.

[0171] - Fiber-reinforced plastics, such as carbon fiber reinforced plastics, glass fiber reinforced plastics, or sheet molding compounds;

[0172] - Wood or plywood, paper, cardboard, wood bonded with organic resin, resin-fabric composites or so-called polymer composites;

[0173] - Insulating foam, especially made of EPS, XPS, PUR, PIR, rock wool, glass wool or foam glass;

[0174] - Coating substrates, such as painted ceramic tiles, painted concrete, coated metal, or painted metal sheets.

[0175] These substrates may be pretreated, in particular by physical and / or chemical cleaning processes or by applying an activator or primer, before the composition is applied.

[0176] It can bond or seal two identical or two different substrates.

[0177] Another subject of the present invention is a method for manufacturing an elastic adhesive or sealant, comprising the following steps:

[0178] (i) Apply the moisture-curing polyurethane composition

[0179] – Apply to the first substrate and allow the composition to contact the second substrate during the open time of the composition, or

[0180] – onto the first and second substrates, and bond the two substrates during the open time of the composition, or

[0181] – to between the two substrates,

[0182] (ii) The composition is then cured by contact with moisture.

[0183] For this method, the composition preferably has a paste consistency and a volatile organic solvent content of less than 5% by weight.

[0184] Another subject of the present invention is a method for manufacturing an elastic coating and / or sealing layer, comprising the following steps:

[0185] (i) Applying the moisture-curing polyurethane composition to a substrate.

[0186] (ii) The composition is cured by contact with moisture.

[0187] For this method, the composition preferably has a low viscosity consistency like a liquid.

[0188] In a preferred embodiment, the elastic coating is part of an elastic waterproofing system.

[0189] In another preferred embodiment, the resilient coating is part of the flooring system, particularly outdoor flooring systems, preferably on balconies, terraces, pedestrian bridges, or stairs.

[0190] The elastic coating preferably contains a combination of at least one oligomeric polyisocyanate and an isocyanate-functionalized polymer with an NCO-functionality of not more than 2. Preferably, it also contains at least one aldehyde imine of formula (VI).

[0191] Preferably, it has a Beck-Koller drying time of no more than 24 hours, preferably no more than 15 hours, an elongation at break of at least 250%, preferably at least 300%, and a Young's modulus of at least 15 MPa, preferably at least 18 MPa, as measured as described in the examples given under the title "Wet-cured polyurethane coatings".

[0192] Another subject of the present invention is a waterproof system comprising the following:

[0193] –Optional primer and / or base coat

[0194] – One or more layers of the moisture-curing polyurethane composition of the present invention, optionally combined with a fiber-reinforced mesh,

[0195] – and optional top coating.

[0196] In waterproofing systems, the moisture-curing polyurethane composition of the present invention is preferably applied by pouring it onto a substrate optionally coated with a primer and / or base coat, and then spreading it evenly to the desired layer thickness, typically in the range of 0.5 to 3 mm dry film thickness, particularly in the range of 0.75 to 1.5 mm dry film thickness, and especially by using a scraper, toothed trowel, scraper, roller or brush.

[0197] In preferred waterproofing systems, fiber-reinforced mesh is used. Preferably, the fiber-reinforced mesh is processed into the first layer of the moisture-curing polyurethane composition of the present invention, and while the composition is still liquid, it is preferably thoroughly bonded into the liquid layer by rollers or brushes. After the composition with the bonded fiber-reinforced mesh has cured, the next layer of the moisture-curing polyurethane composition of the present invention is preferably applied, optionally followed by the application of a topcoat.

[0198] The fiber-reinforced web is preferably a nonwoven polyester fiber web, or more preferably a nonwoven glass fiber web.

[0199] Fiber-reinforced meshes are used as reinforcements in waterproofing systems to increase strength and durability. The randomly oriented fibers in preferred nonwoven fiber meshes impart multidirectional strength to the composition while allowing it to maintain high elasticity. This improves strength, tear resistance, and puncture resistance. Nonwoven glass fiber meshes exhibit particularly ease of handling and can readily match any given surface morphology. It is important that the liquid composition thoroughly wets and penetrates the mesh to ensure complete bonding of the mesh to the composition.

[0200] A further preferred option is a flooring system comprising:

[0201] –Optional base coat

[0202] –Optional base coat,

[0203] - One or more layers of the moisture-curing polyurethane composition of the present invention, optionally in contact with decorative flakes or quartz sand.

[0204] Therefore, the moisture-curing polyurethane composition of the present invention is preferably applied by applying it to a substrate, which is optionally coated with a primer and / or base coat, typically having a layer thickness of 0.05 to 2 mm, particularly 0.1 to 1.5 mm, and is applied in particular using a scraper, toothed trowel, doctor blade, roller or brush.

[0205] The moisture-curing polyurethane composition of the present invention can be used in combination with decorative flakes or quartz sand.

[0206] In one embodiment, decorative flakes or quartz sand are sprinkled onto a static liquid primer, followed by the application of the moisture-curing polyurethane composition of the present invention as a topcoat. This topcoat is preferably free of fillers and pigments and has a clear, transparent appearance.

[0207] In another embodiment, decorative flakes or quartz sand are spread onto the still-liquid moisture-curing polyurethane composition of the present invention. After curing, excess sand is removed. This moisture-curing polyurethane composition of the present invention, spread with flakes or quartz sand, is preferably coated with a topcoat, wherein the topcoat may also be the moisture-curing polyurethane composition of the present invention, optionally a transparent topcoat free of fillers and pigments.

[0208] As a result of the above uses, articles are obtained that are bonded, sealed, and / or coated with the compositions of the present invention. These articles are preferably buildings or infrastructure, or parts thereof, preferably bridges, roofs, balconies, terraces, stairs, or facades, or are industrial or consumer products, or parts thereof, particularly windows, pipes, household appliances, automobiles, buses, trucks, rail vehicles, ships, aircraft, or helicopters.

[0209] The moisture-curing polyurethane compositions described herein offer a number of advantages. They are particularly safe for the environment and application equipment because they contain a very small amount of the monomer isophorone diisocyanate. They cure rapidly to form a substantially non-sticky, elastic material that is very stable against water and UV attack. This allows for use in waterproofing systems on roofs or as an adhesive and / or sealant on ships. Finally, the cured material exhibits excellent mechanical properties, particularly high strength at high elongation. With these characteristics, the compositions of the present invention achieve or exceed the good performance of corresponding compositions with a high content of the monomer isophorone diisocyanate, which contains an aldehydeimide different from that of formula (I). Example

[0210] The following examples illustrate the present invention but are not intended to limit it.

[0211] "Normal climate" refers to a temperature of 23±1℃ and a relative humidity of 50±5%, and is abbreviated as "NC".

[0212] Unless otherwise stated, chemicals were purchased from Sigma-Aldrich Chemie GmbH and used as is.

[0213] A Rheotec RC30 isothermal cone-plate viscometer was used (cone diameter 25 mm, cone angle 1°, cone-plate distance 0.05 mm, shear rate 10 s). -1 )Measure viscosity.

[0214] Preparation of aldehyde imines:

[0215] The amine content (total content of free amino and aldehyde imine) of the prepared aldehyde imine was determined by titration (using acetic acid solution of 0.1N HClO4 with crystal violet as an indicator) and given in mmol N / g.

[0216] Aldehydeimine A1: Contains approximately 20% of the trans, trans-isomer N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-4,4'-methylene-bis(cyclohexylamine).

[0217] 210.4 g (1 mol) of 4,4'-methylene-bis(cyclohexylamine) was added under a nitrogen atmosphere. PACM, containing approximately 20% of the trans, trans-isomer, was liquid at room temperature and solidified at approximately 15°C. It was prepared in a round-bottom flask (from Evonik). Then, 359.5 g (2.1 mol) of 2,2-dimethyl-3-(N-morpholino)propionaldehyde was added with good stirring, followed by removal of volatiles at 80°C and a vacuum of 10 mbar. The resulting product was a clear yellow liquid with a viscosity of 13.9 Pa·s at 20°C and an amine content of 7.68 mmol N / g, corresponding to a calculated aldehyde-imine equivalent of approximately 267 g / Eq.

[0218] Aldehydeimine A2: Contains approximately 50% of the trans, trans-isomer N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-4,4'-methylene-bis(cyclohexylamine).

[0219] 210.4 g (1 mol) of 4,4'-methylene-bis(cyclohexylamine) Containing approximately 50% of the trans, trans-isomer, the product, solid at room temperature and solidifying at approximately 38°C, was melted at 60°C and placed in a round-bottom flask under a nitrogen atmosphere. Then, 359.5 g (2.1 mol) of 2,2-dimethyl-3-(N-morpholino)propionaldehyde was added with good stirring, followed by removal of volatiles at 80°C and a vacuum of 10 mbar. The resulting product was a brown liquid with a viscosity of 13.9 Pa·s at 20°C, which gradually solidified upon cooling to room temperature. The amine content was 7.68 mmol N / g, corresponding to a calculated aldehyde-imine equivalent of approximately 267 g / Eq.

[0220] Aldehydeimine A3: N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine

[0221] 170.3 g (1 mol) of 3-aminomethyl-3,5,5-trimethylcyclohexylamine was added under a nitrogen atmosphere. The IPD (from Evonik) was placed in a round-bottom flask. Then, with good stirring, 359.5 g (2.1 mol) of 2,2-dimethyl-3-(N-morpholino)propionaldehyde was added, followed by removal of volatiles at 80 °C and 10 mbar vacuum. The obtained product was an almost colorless liquid with an amine content of 8.25 mmol N / g, corresponding to a calculated aldehyde-imine equivalent weight of approximately 247 g / Eq.

[0222] Aldehydeimine A4: N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-1,6-hexanediamine

[0223] 166.0 g (1 mol) of 1,6-hexanediamine solution (70 wt% aqueous solution) was placed in a round-bottom flask under a nitrogen atmosphere. Then, 359.5 g (2.1 mol) of 2,2-dimethyl-3-(N-morpholino)propionaldehyde was added with good stirring, followed by removal of volatiles at 80 °C and 10 mbar vacuum. The obtained product was an almost colorless liquid with an amine content of 9.27 mmol N / g, corresponding to a calculated aldehyde imine equivalent weight of approximately 219 g / Eq.

[0224] Aldehydeimine A5: N,N',N”-Tris(2,2-dimethyl-3-(N-morpholino)propylene)polyoxypropylenetriamine

[0225] Under a nitrogen atmosphere, 157.1 g (1 mol N) of polyoxypropylene triamine with an average molecular weight of approximately 440 g / mol was... T-403 (obtained from Huntsman, amine content 6.40 mmol N / g) was placed in a round-bottom flask. Then, 179.8 g (1.05 mol) of 2,2-dimethyl-3-(N-morpholino)propionaldehyde was added with good stirring, followed by removal of volatiles at 80 °C and 10 mbar vacuum. The resulting product was an almost colorless liquid with an amine content of 6.44 mmol N / g, corresponding to a calculated aldehyde-imine equivalent weight of approximately 320 g / Eq.

[0226] Aldehydeimine A6: N,N'-bis(2,2-dimethyl-3-(N-morpholino)propylidene)-1,3-bis(amino-methyl)cyclohexane

[0227] 142.3 g (1 mol) of 1,3-bis(aminomethyl)cyclohexane (1,3-BAC, obtained from Mitsubishi Gas Chem.) was placed in a round-bottom flask under a nitrogen atmosphere. Then, 359.5 g (2.1 mol) of 2,2-dimethyl-3-(N-morpholino)propionaldehyde was added with good stirring, followed by removal of volatiles at 80 °C and 10 mbar vacuum. The product obtained was an almost colorless liquid with an amine content of 8.80 mmol N / g, corresponding to a calculated aldehyde-imine equivalent weight of approximately 233 g / Eq.

[0228] Aldehydeimine A7: Contains approximately 50% of the trans, trans-isomer N,N'-bis(2,2-dimethyl-3-lauroyloxypropylidene)-4,4'-methylene-bis(cyclohexylamine).

[0229] 42.1 g (0.20 mol) of 4,4'-methylene-bis(cyclohexylamine) Containing approximately 50% of the trans, trans-isomer (obtained from BASF), the mixture was melted at 60 °C and placed in a round-bottom flask under a nitrogen atmosphere. Then, 119.5 g (0.42 mol) of 2,2-dimethyl-3-lauroyloxypropionaldehyde was added with good stirring, followed by removal of volatiles at 80 °C and a vacuum of 10 mbar. The resulting product was a clear, brown liquid with a viscosity of 0.52 Pa·s at 20 °C, an amine content of 2.59 mmol N / g, corresponding to a calculated aldehyde-imine equivalent weight of approximately 386 g / Eq.

[0230] Preparation of isocyanate-functionalized polyurethane polymers:

[0231] After derivatization with N-propyl-4-nitrobenzylamine, the content of monomeric diisocyanate was determined by HPLC (detection by photodiode array; 0.04M sodium acetate / acetonitrile mobile phase).

[0232] Polymer P1

[0233] 780g of ethylene oxide-terminated polyoxypropylene triol ( 5031BT, OH- number of 28.0 mg KOH / g, from Covestro) and 220 g isophorone diisocyanate (Ves- IPDI (from Evonik) was reacted at 80°C according to a known procedure to form a mixture with an NCO content of 6.4 wt% and a monomeric isophorone diisocyanate content of about 12 wt%. The volatiles, particularly most of the monomeric isophorone diisocyanate, were then removed from the mixture by distillation (jacket temperature 160°C, 0.1 to 0.005 mbar) in a short-path evaporator. The resulting polymer had an NCO content of 1.9 wt%, a viscosity of 8.2 Pa·s at 20°C, and a monomeric isophorone diisocyanate content of 0.02 wt%.

[0234] Polymer P2:

[0235] 818g polyoxypropylene glycol ( 4200, OH value 28.5 mg KOH / g, from Covestro) and 182 g isophorone diisocyanate ( IPDI (from Evonik) was reacted at 80°C according to a known procedure to form a mixture with an NCO content of 5.1 wt% and a monomeric isophorone diisocyanate content of approximately 9 wt%. The volatiles, particularly most of the monomeric isophorone diisocyanate, were then removed from the mixture by distillation (jacket temperature 160°C, 0.1 to 0.005 mbar) in a short-path evaporator. The resulting polymer had an NCO content of 1.9 wt%, a viscosity of 6.5 Pa·s at 20°C, and a monomeric isophorone diisocyanate content of 0.03 wt%.

[0236] Polymer P3:

[0237] 600g polyoxypropylene glycol ( 1010L, OH value 112mg KOH / g, from Dow) and 400g isophorone diisocyanate ( IPDI (from Evonik) was reacted at 80°C according to a known procedure to form a mixture with an NCO content of 10 wt% and a monomeric isophorone diisocyanate content of approximately 13 wt%. Volatile substances, particularly most of the monomeric isophorone diisocyanate, were then removed from the mixture by distillation (jacket temperature 160°C, 0.1 to 0.005 mbar) in a short-path evaporator. The resulting polymer had an NCO content of 5.5 wt%, a viscosity of 21.8 Pa·s at 20°C, and a monomeric isophorone diisocyanate content of 0.03 wt%.

[0238] Polymer R1:

[0239] 590g polyoxypropylene glycol ( 4200, OH value 28.5 mg KOH / g, from Covestro), 1180g ethylene oxide-terminated polyoxypropylene triol ( MD34-02, OH value 35.0 mg KOH / g, from Shell) and 230g isophorone diisocyanate ( IPDI (from Evonik) was reacted at 80°C according to a known procedure. The resulting polymer had an NCO content of 2.1 wt%, a viscosity of 22.5 Pa·s at 20°C, and a monomeric isophorone diisocyanate content of approximately 2 wt%.

[0240] Polymer R2:

[0241] 725g of ethylene oxide-terminated polyoxypropylene triol ( 5031BT, OH value 28.0 mg KOH / g, from Covestro) and 275g 4,4'-diphenylmethane diisocyanate ( 44MC L (from Covestro) was reacted at 80°C according to a known procedure to form a mixture with an NCO content of 7.6 wt% and a monomer content of about 20 wt% 4,4'-diphenylmethane diisocyanate. Volatiles, particularly the majority of the monomer 4,4'-diphenylmethane diisocyanate, were then removed from the mixture by distillation (jacket temperature 180°C, 0.1 to 0.005 mbar) in a short-path evaporator. The resulting polymer had an NCO content of 1.7 wt%, a viscosity of 19 Pa·s at 20°C, and a 4,4'-diphenylmethane diisocyanate content of 0.04 wt%.

[0242] Polymers P1 to P3 are isophorone-based polymers with low content of monomeric diisocyanates.

[0243] Polymer R1 is a conventional isophorone diisocyanate-based polymer with a high content of monomeric diisocyanate.

[0244] Polymer R2 is a diphenylmethane diisocyanate-based polymer with a low monomer diisocyanate content.

[0245] Moisture-curing polyurethane composition:

[0246] Compositions C1 to C12:

[0247] After removing moisture, the mixture is processed in a centrifugal mixer (SpeedMixer). TMPrepare each composition by mixing the ingredients given in Table 1 or 2 in the given amounts (parts by weight) of DAC 150 (Flacktek Inc.) and store it in a moisture-proof container. Melt the solid aldehyde imine A2 at 60°C before use.

[0248] The following test compositions are used:

[0249] The monomer content of each composition is calculated from the content in the polymer.

[0250] Viscosity was measured at 20°C as previously described after storing the desiccant container in normal climatic conditions for one day (“1d NC”) and after storing it in an oven at 60°C for another 7 days (“7d 60°C”). A small increase indicates good storage stability.

[0251] Under normal climatic conditions, the skinning time (skin formation time) is determined by applying a few grams of the composition to a paperboard at a layer thickness of about 2 mm and gently touching its surface from time to time with an LDPE pipette until no polymer residue is left on the pipette.

[0252] Surface tack was assessed on samples used to determine Shore A hardness after curing under normal climatic conditions for 12 hours, 24 hours, and 2 days.

[0253] Shore A hardness was determined according to DIN 53505 using a cylindrical sample with a diameter of 20 mm and a thickness of 5 mm that had been stored under normal climatic conditions for 7 days.

[0254] To determine the mechanical properties, the composition was poured onto a PTFE-coated foil in a layer thickness of approximately 2 mm and stored under normal climatic conditions for 7 days. Dumbbell-shaped samples with a length of 75 mm, a bridge length of 30 mm, and a bridge width of 4 mm were then punched from the cured film. The tensile strength, elongation (at break), and E-modulus 5% (at 0.5-5% elongation) of the thus prepared samples were determined according to DIN EN 53504 at a crosshead speed of 200 mm / min.

[0255] The cured films of all compositions were uniform and bubble-free.

[0256] The test results are given in Tables 1 and 2.

[0257] Comparative examples are marked with “(Ref.)”.

[0258]

[0259] Table 1: Composition (parts by weight) and test results of compositions C1 to C11. "(Ref.)" refers to "Comparative Examples". 1 5% by weight of salicylic acid in dioctyl phthalate

[0260] 2 5% by weight of dibutyltin dilaurate in diisodecyl phthalate

[0261]

[0262] Table 1: (continued)

[0263]

[0264] Table 2: Composition (parts by weight) and test results of compositions C1, C3, C11, and C12. "(Ref.)" refers to "Comparative Examples".

[0265] 1 5% salicylic acid in dioctyl phthalate

[0266] 2 5% by weight of dibutyltin dilaurate in diisodecyl phthalate

[0267] Moisture-curing polyurethane adhesives:

[0268] Compositions C13 to C16:

[0269] Each composition was prepared by mixing the ingredients given in Table 3 in a given amount (parts by weight) using a planetary mixer under vacuum and moisture-free conditions, and then storing it in a moisture-proof container.

[0270] Before adding, solid aldehyde imine A2 is melted at 60°C.

[0271] By using 300g of diisodecyl phthalate and 48g of 4,4'-diphenylmethane diisocyanate ( 44MC L (from Covestro) was placed in a vacuum mixer, and the mixture was heated to 40°C. Then, 27g of monobutylamine was added dropwise under vigorous stirring to prepare a thickening paste. The resulting paste was further stirred under vacuum and cooled for 1 hour.

[0272] The following test compositions are used:

[0273] The monomer content of each composition is calculated from the content in the polymer and IPDI-isocyanurate.

[0274] As described for composition C1, the skin formation time (epidermal formation time) and Shore A hardness were determined.

[0275] To determine mechanical properties, each composition was pressed between two sheets of waxed transfer paper to form a 2 mm thick film, which was then stored under normal climatic conditions. After removing the waxed paper, dumbbell-shaped samples were punched out from the cured film, and tensile strength, elongation, and E-modulus 5% were tested as described for composition C1.

[0276] All adhesives produced a uniform, bubble-free cured film.

[0277] The test results are given in Table 3.

[0278] Comparative examples are marked with “(Ref.)”.

[0279]

[0280] Table 3: Composition (parts by weight) and test results of compositions C13 to C16.

[0281] "(Ref.)" refers to the "Comparative Example".

[0282] 1 T1890 / 100 (from Evonik), NCO content is 17.3% by weight, approximately 0.5% by weight.

[0283] Amount -% of monomer IPDI

[0284] 2 diisodecyl phthalate

[0285] 3 BLH (from Omya)

[0286] 4 5% by weight of dibutyltin dilaurate in diisodecyl phthalate

[0287] 5 Not measured

[0288] Moisture-curing polyurethane coatings:

[0289] Compositions C17 to C22:

[0290] Each composition was prepared by mixing the ingredients given in Table 4 in a centrifugal mixer in a given amount (parts by weight) while removing moisture, and stored in a moisture-proof container. Before use, solid aldehyde imine A2 was melted at 60°C while salicylic acid was dissolved in 1-methoxy-2-propyl acetate.

[0291] The following test compositions are used:

[0292] The monomer content of each composition is calculated from the content in the polymer and the IPDI-isocyanurate solution.

[0293] Viscosity was measured at 500 rpm using a rotary diluent type viscometer with a spherical rotor DV2011 at 20°C, for the first time after storing the desiccant container in normal climate for 1 day (“1d NC”) and again after storing the desiccant container in an oven at 40°C for 21 days (“21d 40°C”).

[0294] According to ASTM D5895, the curing rate (“BK drying time”) was determined using a Beck-Koller drying time recorder at 20°C / 45% relative humidity.

[0295] To determine the mechanical properties, two cured films were prepared for each coating. To prepare the films, a first layer with a thickness of 800 μm was applied using a doctor blade and cured in normal climatic (NC) conditions for 24 hours; then a second layer with a thickness of 400 μm was applied on top at a 90° angle and cured again in NC for 24 hours; the double-layer film was then placed in an oven at 60°C for 72 hours. After an additional 24 hours in NC, rod-shaped test specimens with a length of 100 mm and a width of 25 mm were punched from the film, and tensile strength, elongation at break, and Young's modulus were determined according to BS EN ISO 527-3 at a crosshead speed of 180 mm / min.

[0296] All coatings cured films were uniform and bubble-free.

[0297] The results are given in Table 4.

[0298] Comparative examples are marked with “(Ref.)”.

[0299]

[0300]

[0301] Table 4: Composition (parts by weight) and test results of compositions C17 to C22.

[0302] "(Ref.)" refers to the "Comparative Example".

[0303] 1 Z 4470SN (70% wt solution in Solventnaphtha 100, with NCO content of approximately 12.0% wt% and monomeric IPDI of approximately 0.35% wt%, from Covestro)

[0304] 2 Aluminum trioxide packing

[0305] 3Undetermined

Claims

1. A moisture-curing polyurethane composition comprising – A polymer with at least one isocyanate functional, wherein the monomer isophorone diisocyanate content is less than 0.5% by weight, obtained by the reaction of isophorone diisocyanate and at least one polyol, and – At least one aldehyde imine of formula (I), in R 1 and R 2 are independently of one another hydrogen or methyl, R 3 and R 4 are identical or different C1to C4alkyl, and R 5 and R 6 are connected together to form a C4to C6alkylene group optionally containing an ether oxygen; and The composition contains at least one latent curing agent selected from aldimines other than those of formula (I), oligomeric polyisocyanates, and other components of stabilizers.

2. The composition according to claim 1, wherein the aldehyde imine of formula (I) is a liquid at 23°C.

3. The composition of claim 1, wherein R 1 and R 2 are each hydrogen.

4. The composition according to any one of claims 1-3, wherein R 3 and R 4 All are methyl, and R 5 and R 6 Together they form 3-oxa-1,5-pentylene, which, with R 5 and R 6 The bonded nitrogen atoms together form a morpholine ring.

5. The composition according to any one of claims 1-3, wherein the aldolimine is a mixture of isoaldolimines containing less than 35% of the trans, trans-isomers.

6. The composition according to any one of claims 1-3, wherein the aldolimine is a mixture of isoform aldolimines containing less than 30% of the trans, trans-isomers.

7. The composition according to any one of claims 1-3, wherein the aldolimine is a mixture containing up to 25% of the trans, trans-isomer of the isoform aldolimine.

8. The composition according to any one of claims 1-3, wherein the isocyanate-functionalized polymer has a monomer isophorone diisocyanate content of less than 0.3% by weight and an NCO- content of 1-10% by weight, which is obtained by reacting isophorone diisocyanate with at least one polyether polyol with an OH value of 10-250 mg KOH / g at an NCO / OH molar ratio of 3 / 1-10 / 1, followed by removing most of the monomer isophorone diisocyanate by distillation.

9. The composition according to any one of claims 1-3, wherein the composition contains a monomeric diisocyanate in an amount of less than 0.1% by weight relative to the total composition.

10. The composition according to claim 1, wherein the composition contains at least one curing agent of at least one aldehyde imine of formula (I), which is at least one aldehyde imine of formula (Va). in R 3 and R 4 are the same or different C1to C4alkyl, or are linked together to form a C4to C6alkylene group, R 5 , R 6 are the same or different C1to C8alkyl groups optionally containing an ether oxygen, or are linked together to form a C4to C6alkylene group optionally containing an ether oxygen.

11. The composition according to claim 10, wherein the weight ratio between the aldimine of formula (I) and the aldimine of formula (Va) is from 10 / 90 to 80 / 20.

12. The composition according to claim 10, wherein the weight ratio between the aldimine of formula (I) and the aldimine of formula (Va) is from 20 / 80 to 75 / 25.

13. The composition of claim 1, wherein it contains at least one oligomeric polyisocyanate, said oligomeric polyisocyanate being an oligomer of at least one isophorone diisocyanate.

14. A cured composition obtained by contacting moisture with the composition according to any one of claims 1 to 13.

15. A method for preparing an elastic adhesive or sealant, comprising the following steps: (i) Applying the composition according to any one of claims 1 to 13 – Apply to the first substrate and allow the composition to contact the second substrate during the open time of the composition, or – to the first substrate and the second substrate and to bond the two substrates during the open time of the composition, or – to between the two substrates, (ii) The composition is then cured by contact with moisture.

16. A method for manufacturing an elastic coating and / or sealing layer, comprising the following steps: (i) applying a composition according to any one of claims 1 to 13 onto a substrate, (ii) curing the composition by contact with moisture.

17. A waterproofing system consisting of: - optionally a primer and / or a base coat, - one or more layers of a composition according to any one of claims 1 to 14, optionally in combination with a fibrous reinforcement mesh, - and optionally a top coat.

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