Solvent for aromatic carboxylic or sulfonic acids

Abstract

To provide a solvent for aromatic carboxylic or sulfonic acids that overcomes the disadvantages of the prior art in relation to dissolution capacity, volatility and compatibility with polymer compositions.SOLUTION: The invention relates to the use of at least one polyether having blocked hydroxyl groups as a solvent for at least one aromatic carboxylic or sulfonic acid, and to the solution obtained therefrom. The polyether having blocked hydroxyl groups is not volatile and exhibits a surprisingly high dissolving capacity for the aromatic carboxylic or sulfonic acid. The acid solution is very compatible in curable compositions and does not cause any emission or odor or migration effects. The acid solution is particularly suitable as a constituent of polyurethane compositions having latent curing agents for accelerating the hydrolysis of the latent reactive groups.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a solvent for aromatic carboxylic or sulfonic acids, the acid solutions obtained therefrom and curable compositions, particularly polyurethane compositions, containing them. [Background technology]

[0002] Aromatic carboxylic or sulfonic acids are often used as catalysts for polymer compositions, for example based on polyurethanes or epoxy resins. These acids are often high-melting solids that must be dissolved in order to be used in the polymer composition. However, the use of traditional solvents is increasingly avoided, since they are volatile, flammable, often toxic, cause VOC emissions, shrinkage and odors during use, and often require occupational safety measures. Alternatively, glycols or polyols can be used as non-volatile solvents. However, these are very hydrophilic due to their hydroxyl group content and are not compatible with many polymer compositions. The non-volatile solvent used can also be a plasticizer, for example a phthalate or an adipic acid ester, such as diisodecyl phthalate (DIDP) or di(2-ethylhexyl) adipate (DOA). However, most plasticizers have a poor ability to dissolve the acid. This means that only very dilute solutions are obtained or that the solution needs to be constantly heated to prevent the acid from crystallizing. Additionally, plasticizers can further impart drawbacks to the polymer composition, such as haze or migration effects, such as leaching or staining.

[0003] In view of the above, there is a need for a solvent that has high dissolving capacity for aromatic carboxylic or sulfonic acids, is non-volatile and non-toxic, and is particularly suitable for use in polymer compositions. Summary of the Invention [Problem to be solved by the invention]

[0004] It is therefore an object of the present invention to provide a solvent for aromatic carboxylic or sulfonic acids which overcomes the deficiencies of the prior art with regard to dissolving capacity, volatility and compatibility with polymer compositions. [Means for solving the problem]

[0005] This object is achieved by using at least one polyether with blocked hydroxyl groups according to claim 1. Despite their polymer structure, polyethers with blocked hydroxyl groups show a surprisingly high dissolving ability for aromatic carboxylic or sulfonic acids, are very non-volatile and non-toxic. This allows highly concentrated acid solutions that are surprisingly mobile and can be used for long periods without heating without crystallization or precipitation of the acid. Such acid solutions can therefore be easily produced, transported, shipped and stored. They have excellent compatibility in polymer compositions, especially polyurethane compositions, and have very good compatibility therein, even with isocyanate groups, without causing migration effects or clouding. They are particularly advantageous when acid solutions are metered only in the course of dispensing the composition, for example in the filling of cartridges or tubular bags, where only small absolute amounts of solution are possible in the case of normal dispensing systems, and therefore high acid concentrations are required to ensure the addition of sufficient amounts of acid.

[0006] Particularly advantageously, the acid solution of the present invention is used in one-part moisture-curing polyurethane compositions containing isocyanate groups and latent hardeners, in particular aldimines or oxazolidines. The aromatic carboxylic or sulfonic acid here acts as a catalyst for the hydrolysis of the latent hardener. Such compositions cure without blistering and without odor generation under the influence of moisture, show few migration-related defects such as leaching or staining after curing, and are particularly suitable as adhesives, sealants or coatings. In the prior art, di(2-ethylhexyl) adipate (DOA) is typically used as a solvent for aromatic carboxylic or sulfonic acids in such compositions. However, this allows only very dilute solutions to be achieved, and DOA tends to have a migration effect.

[0007] Further aspects of the invention are the subject matter of the further independent claims. Particularly preferred embodiments of the invention are the subject matter of the dependent claims. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention provides the use of at least one polyether having blocked hydroxyl groups as a solvent for at least one aromatic carboxylic or sulfonic acid.

[0009] "Polyether" refers to a group of molecules or oligomeric and / or polymeric molecules composed primarily of alkyleneoxy repeating units.

[0010] A "blocked hydroxyl group" refers to a hydroxyl group that has been converted, through a chemical reaction, into a group that is non-reactive toward isocyanate groups.

[0011] "Molecular weight" refers to the molar mass (g / mol) of a molecule or molecular residue. "Average molecular weight" refers to the number average molecular weight M of a polydisperse mixture of oligomeric or polymeric molecules or molecular residues. n This is typically determined by gel permeation chromatography (GPC) against polystyrene as a standard.

[0012] "Aromatic" refers to an acid or isocyanate in which the acid or isocyanate group is bonded directly to an aromatic carbon atom.

[0013] "Curable composition" refers to a composition that contains a polymerizable polymer, which is capable of being cured or acquiring increased mechanical strength through a crosslinking reaction of its reactive groups.

[0014] "Plasticizer" refers to a non-volatile substance that reduces the viscosity of a polymer without being chemically incorporated into the polymer and that exerts a plasticizing effect thereon.

[0015] Substance names beginning with "poly", such as polyamine, polyol or polyisocyanate, refer in a formal sense to substances that contain, per molecule, two or more functional groups appearing in the name.

[0016] A curable composition that is termed "storage stable" or "storable" is one that can be stored in a suitable container at room temperature for an extended period of time, typically at least 3 to 6 months or more, without its application or properties of use being altered to the extent relevant to its use by such storage.

[0017] A "primary amino group" refers to an amino group that is bonded to a single organic group and has two hydrogen atoms; a "secondary amino group" refers to an amino group that is bonded to two organic groups which together may form part of a ring and has one hydrogen atom; and a "tertiary amino group" refers to an amino group that is bonded to three organic groups, two or three of which may be part of one or more rings, and has no hydrogen atoms.

[0018] A "one-part" composition refers to a hardenable composition in which all components of the composition are mixed and stored together in the same container and which hardens with moisture.

[0019] A "two-part" composition refers to a curable composition in which the components of the composition are two distinct components that are stored in separate containers and are not mixed with each other until just before or during application of the composition.

[0020] "Room temperature" refers to a temperature of 23°C.

[0021] Polyethers having blocked hydroxyl groups are essentially free of unblocked hydroxyl groups, where "essentially free" means that 95%, preferably 99%, in particular 99.9%, and most preferably 100% of the hydroxyl groups present are blocked.

[0022] The polyether with blocked hydroxyl groups preferably does not contain reactive groups which enter into crosslinking reactions with the usual components in moisture or in the curable composition, and therefore in particular does not contain isocyanate and silane groups.

[0023] Polyethers with blocked hydroxyl groups are especially liquid at room temperature.

[0024] The polyether having blocked hydroxyl groups preferably has a viscosity in the range of 30 to 5,000 mPa·s, more preferably 40 to 2,000 mPa·s, particularly preferably 50 to 1,000 mPa·s, and especially 50 to 500 mPa·s at 20° C. In this specification, the viscosity is measured at a cone diameter of 25 mm, a cone angle of 1°, a cone tip-plate distance of 0.05 mm, and a shear rate of 10 s -1 The viscosity is determined using a cone and plate viscometer. This results in a highly concentrated acid solution that is easy to handle.

[0025] The blocked hydroxyl groups are preferably selected from the group consisting of ester groups, acetoester groups, carbonate groups and urethane groups.

[0026] These ester groups, acetoester groups, carbonate groups and urethane groups preferably have 1 to 15 carbon atoms.

[0027] Particular preference is given to ester or urethane groups, as hydroxyl groups can be particularly easily converted into these groups, which are particularly stable and compatible with aromatic carboxylic or sulfonic acids.

[0028] Particular preference is given to ester groups, in particular ester groups having 1 to 8 carbon atoms.

[0029] Most preferred are acetate groups. Polyethers having hydroxyl groups blocked in the form of acetate groups are particularly low in viscosity, can be obtained in a very simple manner and are particularly inexpensive.

[0030] Also preferred are urethane groups, especially phenylurethane groups or p-toluenesulfonylurethane groups.Polyethers containing such blocked hydroxyl groups have manageable viscosities and can be prepared in a particularly simple manner.

[0031] A preferred acetoester group is an acetoacetate group.

[0032] A preferred carbonate group is a methyl carbonate group.

[0033] They have low viscosity and are obtained from inexpensive raw materials.

[0034] The repeat units present in the polyethers having blocked hydroxyl groups are preferably 1,2-ethyleneoxy, 1,2-propyleneoxy, 1,3-propyleneoxy, 1,2-butyleneoxy or 1,4-butyleneoxy groups, in particular 1,2-propyleneoxy groups.

[0035] Preferably, 70% to 100% by weight, particularly 80% to 100% by weight of the repeating units are made up of 1,2-propyleneoxy groups, and 0% to 30% by weight, particularly 0% to 20% by weight of the repeating units are made up of 1,2-ethyleneoxy groups.

[0036] More preferably, the repeat units consist entirely of 1,2-propyleneoxy groups.

[0037] Such polyethers are readily available and are hydrophobic, making them particularly suitable as components of curable compositions having low water absorption and good stability.

[0038] The polyethers having blocked hydroxyl groups preferably have an average molecular weight M in the range of 600 to 10,000 g / mol, more preferably 700 to 5,000 g / mol, especially 800 to 2,500 g / mol, determined by gel permeation chromatography (GPC) against polystyrene as standard using tetrahydrofuran as the mobile phase, a refractive index detector and an evaluation from 200 g / mol. n has.

[0039] Such polyethers with blocked hydroxyl groups have low viscosity, thereby allowing for solutions that are easy to handle, and do not produce emissions or odors in the curable composition.

[0040] The polyether having blocked hydroxyl groups is preferably polyoxypropylene monools starting from alcohols, in particular starting from n-butanol, having an OH number in the range from 25 to 90 mg KOH / g, preferably from 50 to 80 mg KOH / g; polyoxypropylene diols having an OH number in the range from 12 to 155 mg KOH / g, preferably from 22 to 125 mg KOH / g and in particular from 45 to 125 mg KOH / g, - polyoxypropylene triols, optionally ethylene oxide terminated, starting from trimethylolpropane or in particular from glycerol and having an average OH functionality ranging from 2.2 to 3 and an OH number ranging from 22 to 230 mg KOH / g, preferably from 56 to 165 mg KOH / g, and - polyoxypropylene polyols starting from sugar alcohols, in particular threitol, erythritol, xylitol, mannitol or sorbitol as starting molecules (initiator molecules), with an average OH functionality ranging from 3 to 6; The polyether is derived from at least one hydroxy-functional polyether selected from the group consisting of: Such polyethers having blocked hydroxyl groups are commercially available as Sanflex® SPX-80 (from Sanyo Chem. Ind.).

[0041] Among these, preference is given to polyoxypropylene mono- or diols which start from alcohols, in particular from n-butanol.

[0042] Particular preference is given to polyoxypropylene diols, which are particularly inexpensive.

[0043] The preferred polyethers having blocked hydroxyl groups can be prepared by simple methods from readily available commercial products and have low viscosity, allowing for highly concentrated acid solutions coupled with ease of handling.

[0044] Polyethers having blocked hydroxyl groups are obtainable in particular by reacting at least one hydroxy-functional polyether with at least one suitable blocking agent for hydroxyl groups.

[0045] For the reaction, blocking agent is used in at least stoichiometric amount relative to hydroxyl group, so that hydroxyl group is essentially completely blocked, and thus the resulting polyether is essentially free of hydroxyl group. For blocking, a method customary for each reactive group is used, and optionally a catalyst or a solvent is additionally used. If blocking reaction forms elimination products, these are removed from the reaction mixture by suitable methods, in particular by distillation.

[0046] Suitable blocking agents are nucleophilic compounds that undergo addition or substitution reactions with hydroxyl groups.

[0047] Particularly suitable are carboxylic acids, carbonyl chlorides, carboxylic esters or anhydrides, diketenes, 2,2,5-trimethyl-4H-1,3-dioxin-4-one, alkyl acetoacetates, dialkyl carbonates, monoisocyanates, (meth)acrylamides, methylene malonates or cyanoacrylates.

[0048] Preference is given to carboxylic acids, carbonyl chlorides, carboxylic esters or carboxylic anhydrides with the formation of a blocked hydroxyl group in the form of an ester group. Among these, preference is given to carboxylic anhydrides or carboxylic esters, in particular acetic anhydride.

[0049] In the case of acetic anhydride as the blocking agent, the reaction releases acetic acid and forms a blocked hydroxyl group in the form of an acetate group.

[0050] In the case of isopropenyl acetate as blocking agent, the reaction releases acetone and likewise forms a blocked hydroxyl group in the form of an acetate group.

[0051] Furthermore, preference is given to diketenes with the formation of blocked hydroxyl groups in the form of acetoester groups, sterically hindered alkyl acetoacetates such as 2,2,5-trimethyl-4H-1,3-dioxin-4-one or especially tert-butyl acetoacetate.

[0052] Preference is further given to dialkyl carbonates, especially dimethyl carbonate, with the formation of blocked hydroxyl groups in the form of carbonate groups, especially methyl carbonate groups.

[0053] Further preference is given to monoisocyanates with the formation of blocked hydroxyl groups in the form of urethane groups. Preference is given to phenylisocyanate or p-toluenesulfonyl isocyanate.

[0054] Suitable hydroxy-functionalized polyethers are in particular those having an average OH functionality in the range from 1 to 6 and an average molecular weight in the range from 500 to 10,000 g / mol, more preferably from 600 to 5,000 g / mol and in particular from 700 to 2,500 g / mol.

[0055] Preference is given to polyoxypropylene monools having an OH value in the range of 25 to 90 mg KOH / g, preferably 50 to 80 mg KOH / g, in particular polyoxypropylene monools starting from alcohols, in particular those starting from methanol, ethanol, propanol, isopropanol, n-butanol, isobutanol, tert-butanol, pentanol, hexanol, 2-ethylhexanol, lauryl alcohol, myristyl alcohol, palmityl alcohol, allyl alcohol, cyclohexanol, benzyl alcohol or phenol. Among these, preference is given to polyoxypropylene monools starting from alkyl alcohols, in particular those starting from methanol, ethanol or n-butanol. Particular preference is given to polyoxypropylene monools starting from n-butanol, having an average molecular weight Mn in the range of 650 to 2,000 g / mol, in particular 700 to 1,500 g / mol. Polyoxypropylene monols starting from n-butanol are commercially available, for example, as Synalox® 100-20B, Synalox® 100-40B, or Synalox® 100-85B (all from DowDuPont Inc.).

[0056] Also preferred are polyoxypropylene diols having an OH value in the range of 12 to 155 mg KOH / g, preferably 22 to 125 mg KOH / g, in particular 45 to 125 mg KOH / g.

[0057] Also preferred are polyoxypropylene triols, optionally terminated with ethylene oxide, starting from trimethylolpropane or especially glycerol, having an average OH functionality in the range from 2.2 to 3 and an OH number in the range from 22 to 230 mg KOH / g, preferably from 56 to 165 mg KOH / g.

[0058] Also preferred are polyoxypropylene polyols having an average OH functionality of at least 3, particularly in the range of 3 to 6, which are made from sugar alcohols as starting materials, particularly threitol, erythritol, xylitol, mannitol or sorbitol as starting molecules (initiator molecules).

[0059] Suitable aromatic carboxylic or sulfonic acids are in particular benzoic acid, salicylic acid, 2-nitrobenzoic acid, 2-chlorobenzoic acid, p-toluenesulfonic acid or a mixture of two or more of the aforementioned acids.

[0060] The aromatic carboxylic or sulfonic acid is preferably selected from the group consisting of benzoic acid, 2-nitrobenzoic acid, salicylic acid and p-toluenesulfonic acid.

[0061] Particular preference is given to salicylic acid.

[0062] The preferred aromatic carboxylic or sulfonic acids are readily available and allow particularly rapid hydrolysis of latent hardeners bearing aldimino, ketimino, enamino or oxazolidino groups, which are solids with high melting points at room temperature and therefore require a readily available solvent in the curable composition.

[0063] The uses described herein result in an acid solution.

[0064] Thus, the present invention further provides an acid solution from the uses described herein.

[0065] Such acid solutions are particularly suitable as catalysts for the hydrolysis of latent hardeners having aldimino, ketimino, enamino or oxazolidino groups, especially in curable compositions containing isocyanate groups.

[0066] More specifically, the acid solution is liquid at room temperature and is essentially free of undissolved aromatic carboxylic or sulfonic acid fractions.

[0067] This solution is preferably liquid at 4° C. and can be stored in a closed container at 4° C. for 7 days without crystallization of the aromatic carboxylic or sulfonic acid fraction.

[0068] The acid solution preferably contains 2.5% to 25% by weight of aromatic carboxylic or sulfonic acid and 50% to 97.5% by weight, in particular 75% to 97.5% by weight, of polyether with blocked hydroxyl groups.

[0069] The acid solution more preferably contains 5% to 20% by weight, in particular 7.5% to 15% by weight, of an aromatic carboxylic acid or sulfonic acid and 80% to 95% by weight, in particular 85% to 92.5% by weight, of a polyether having blocked hydroxyl groups.

[0070] The acid solution preferably has a viscosity in the range of 40 to 8,000 mPa·s, more preferably 50 to 4,000 mPa·s, particularly preferably 60 to 2,000 mPa·s, and especially 70 to 1,000 mPa·s at 20° C. In this specification, this viscosity is measured at a cone diameter of 25 mm, a cone angle of 1°, a cone tip-plate distance of 0.05 mm, and a shear rate of 10 s -1 The viscosity is determined using a cone-plate viscometer.

[0071] The acid solution is preferably prepared by metering aromatic carboxylic acid or sulfonic acid into the initial charge of blocked hydroxyl-containing polyether with stirring at a temperature in the range of 15 to 100° C., particularly 20 to 90° C., or by dissolving a mixture containing blocked hydroxyl-containing polyether and aromatic carboxylic acid or sulfonic acid at a temperature in the range of 15 to 100° C., particularly 20 to 90° C. In either case, stirring is continued until the aromatic carboxylic acid or sulfonic acid is completely dissolved. The acid solution is preferably stored in a sealed container until further use.

[0072] Optionally, the acid solution may contain, in addition to the polyether with blocked hydroxyl groups and the aromatic carboxylic or sulfonic acid, additional substances, in particular plasticizers, additional acids, acid esters, acid anhydrides or silyl esters of acids or catalysts, in particular at least one catalyst for promoting the reaction of isocyanates, in particular organotin(IV) compounds, bismuth(III) or zirconium(IV) complexes or compounds containing tertiary amino groups, such as in particular 2,2′-dimorpholinodiethyl ether (DMDEE).

[0073] The solution preferably does not contain additional substances.

[0074] Preference is given to using an acid solution as catalyst for the crosslinking of the curable composition.

[0075] The curable composition preferably comprises isocyanate groups and / or silane groups, especially isocyanate groups.

[0076] The acid solution is preferably used in compositions containing isocyanate groups to promote the hydrolysis of at least one latent hardener. Polyethers with blocked hydroxyl groups have particularly good compatibility in such compositions and, even together with isocyanate groups, have a particularly high storage stability.

[0077] Accordingly, the present invention further provides a hardenable composition comprising an acid solution as described herein.

[0078] The acid solution present in the composition may be prepared separately and mixed into the composition, or it may be prepared directly in the composition at any point.

[0079] The acid solution present in the composition is preferably prepared separately.

[0080] The curable composition preferably contains from 0.01% to 0.5% by weight, especially from 0.02% to 0.25% by weight, of dissolved aromatic carboxylic or sulfonic acid.

[0081] The curable composition preferably comprises at least one polyisocyanate or polymer containing isocyanate groups, at least one latent hardener having at least one aldimino, ketimino, enamino or oxazolidino group, - at least one polyether having blocked hydroxyl groups as defined above, and at least one aromatic carboxylic or sulfonic acid Includes.

[0082] Aliphatic, cycloaliphatic or aromatic diisocyanates, in particular hexamethylene 1,6-diisocyanate (HDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate or IPDI), perhydro(diphenylmethane 2,4'- and / or 4,4'-diisocyanate) (H 12 Preference is given to diphenylmethane 4,4'-diisocyanate (MDI) with or without fractions of diphenylmethane 2,4'- and / or 2,2'-diisocyanate or tolylene 2,4-diisocyanate or mixtures thereof with tolylene 2,6-diisocyanate (TDI), mixtures of MDI with MDI analogues (polymeric MDI or PMDI) or oligomeric isocyanates.

[0083] Suitable oligomeric isocyanates are in particular HDI biurets such as Desmodur® N100 or N3200 (from Covestro AG), Tolonate® HDB or HDB-LV (from Vencorex Holding SAS) or Duranate® 24A-100 (from Asahi Kasei); HDI isocyanurates such as Desmodur® N3300, N3600 or N3790 BA (all from Covestro AG), Tolonate® HDT, HDT-LV or HDT-LV2 (from Vencorex Holding SAS), Duranate® TPA-100 or THA-100 (from Asahi Kasei Corporation) or Coronate® HX (from Tosoh Corporation); HDI uretdiones, such as Desmodur® XP2410 (from Covestro AG); HDI iminooxadiazinediones, such as Desmodur® VP LS 2102 (from Covestro AG); IPDI isocyanurates, for example in solution, such as Desmodur® Z4470 (from Covestro AG) or in solid form, such as Vestanat® T1890 / 100 (from Evonik Industries AG); TDI oligomers, such as Desmodur® IL (from Covestro AG); or mixed isocyanurates based on TDI / HDI, such as Desmodur® HL (from Covestro AG).

[0084] Particularly preferred polyisocyanates are HDI, IPDI, TDI, MDI or forms of MDI that are liquid at room temperature.

[0085] The forms of MDI that are liquid at room temperature are either 4,4'-MDI liquefied by partial chemical modification (in particular carbodiimidization or uretonimine formation or adduct formation with polyols) or it is a mixture of 4,4'-MDI with other MDI isomers (2,4'-MDI and / or 2,2'-MDI), obtained selectively by blending or obtained by the manufacturing process, and / or MDI oligomers and / or MDI analogues (polymeric MDI or PMDI).

[0086] Further particularly preferred polyisocyanates are IPDI isocyanurates or TDI oligomers or mixed isocyanurates based on TDI / HDI or HDI oligomers.

[0087] Suitable polymers containing isocyanate groups are obtained in particular from the reaction of at least one polyol with a stoichiometric amount of at least one diisocyanate, preferably MDI, TDI, IPDI or HDI. The reaction is preferably carried out at temperatures ranging from 20 to 160° C., in particular from 40 to 140° C., with the exclusion of moisture, optionally in the presence of a suitable catalyst. The polymers are optionally prepared additionally using plasticizers or solvents, in which case the plasticizers or solvents used do not contain groups reactive towards isocyanates.

[0088] When used in a two-part composition, the excess diisocyanate is preferably selected so as to leave, after reaction of all hydroxyl groups in the isocyanate group-containing polymer, a content of isocyanate groups in the range of 1% to 30% by weight, preferably 1.5% to 25% by weight, more preferably 2% to 20% by weight, based on the total polymer.

[0089] Such polymers containing isocyanate groups preferably have an average molecular weight M in the range of 350 to 6,000 g / mol. n has.

[0090] When used in one-component compositions, the NCO / OH ratio is preferably in the range of 1.3 / 1 to 10 / 1. The monomeric diisocyanates remaining in the reaction mixture after the reaction of the OH groups can be removed, in particular by distillation. The polymers obtained preferably have a content of isocyanate groups in the range of 0.5% to 10% by weight, in particular 1% to 5% by weight, more preferably 1% to 3% by weight, and preferably have an average molecular weight M in the range of 1,500 to 20,000 g / mol, in particular 2,000 to 15,000 g / mol. n When the excess monomeric diisocyanate is removed by distillation, the NCO / OH ratio during the reaction is preferably in the range of 4 / 1 to 7 / 1, and the resulting isocyanate group-containing polymer contains, after distillation, preferably 0.5% by weight or less, more preferably 0.3% by weight or less of monomeric diisocyanate. The monomeric diisocyanate is removed by short-path distillation, especially under reduced pressure.

[0091] If excess monomeric diisocyanates are not removed from the polymer, the NCO / OH ratio in the reaction is preferably in the range of 1.3 / 1 to 2.5 / 1.

[0092] Suitable polyols are commercially available polyols or mixtures thereof, in particular: - the polymerization products of polyether polyols, in particular polyoxyalkylene diols and / or polyoxyalkylene triols, in particular ethylene oxide, or 1,2-propylene oxide, or 1,2- or 2,3-butylene oxide, or oxetane, or tetrahydrofuran or mixtures thereof, which are reacted with starter molecules (initiator molecules) having two or three active hydrogen atoms, in particular water, ammonia or compounds having several OH or NH groups, such as, for example, ethane-1,2-diol, propane-1,2- or -1,3-diol, neopentyl glycol, diethylene The polymerization can be carried out using starter molecules (initiator molecules) such as ethylene glycol, triethylene glycol, the isomeric dipropylene glycols or tripropylene glycols, the isomeric butanediols, pentanediols, hexanediols, heptanediols, octanediols, nonanediols, decanediols, undecanediols, cyclohexane-1,3- or -1,4-dimethanol, bisphenol A, hydrogenated bisphenol A, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol or aniline or mixtures of the aforementioned compounds. Also suitable are polyether polyols in which polymer particles are dispersed, in particular those containing styrene / acrylonitrile (SAN) particles or polyurea or polyhydrazodicarbonamide (PHD) particles.

[0093] Preferred polyether polyols are polyoxypropylene diols or triols or so-called ethylene oxide-terminated (EO-capped or EO-terminated) polyoxypropylene diols or triols, the latter being mixed polyoxyethylene / polyoxypropylene polyols, which are obtained in particular by further alkoxylation of polyoxypropylene diols or triols with ethylene oxide, as a result of a polypropoxylation reaction, resulting in primary hydroxyl groups.

[0094] Preferred polyether polyols have unsaturation levels of less than 0.02 meq / g, especially less than 0.01 meq / g. - polyester polyols, also called oligoesterols, which are prepared by known processes, in particular by polycondensation of hydroxycarboxylic acids or lactones or of aliphatic and / or aromatic polycarboxylic acids with di- or polyhydric alcohols. Preference is given in particular to polyesterdiols from the reaction of dihydric alcohols, such as 1,2-ethanediol, diethylene glycol, 1,2-propanediol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, glycerol, 1,1,1-trimethylolpropane or mixtures of the aforementioned alcohols, with organic dicarboxylic acids or their anhydrides or esters, such as, in particular, succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, dodecanedicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexane-1,2-dicarboxylic acid, cyclohexane-1,3-dicarboxylic acid or cyclohexane-1,4-dicarboxylic acid or mixtures of the aforementioned acids, or polyesterpolyols formed from lactones, such as, in particular, ε-caprolactone. Particular preference is given to polyester polyols formed from adipic acid or sebacic acid or dodecanedicarboxylic acid and hexanediol or neopentyl glycol. Polycarbonate polyols, obtainable, for example, by reaction of the alcohols mentioned above used to form the polyester polyols with dialkyl carbonates, diaryl carbonates or phosgene. - block copolymers having at least two OH groups and having at least two different blocks with polyether, polyester and / or polycarbonate structures of the type mentioned above, in particular polyether polyester polyols. - Polyacrylate or polymethacrylate polyols. - polyhydroxy-functional fats and oils, such as natural fats and oils, in particular castor oil; or polyols obtained by chemical modification of natural fats and oils (called oleochemical polyols), for example epoxy polyesters or epoxy polyethers obtained by epoxidation of unsaturated oils followed by ring opening with carboxylic acids or alcohols or polyols obtained by hydroformylation and hydrogenation of unsaturated oils; or polyols obtained from natural fats and oils by decomposition processes, such as alcoholysis or ozonolysis followed by chemical coupling, for example by transesterification or dimerization, of the decomposition products thus obtained or their derivatives. Suitable decomposition products of natural fats and oils are in particular fatty acids and fatty alcohols as well as fatty acid esters, in particular methyl esters (FAMEs), which can be derivatized, for example, by hydroformylation and hydrogenation, to hydroxy fatty acid esters. - polyhydrocarbon polyols, also called oligohydrocarbonols, such as in particular polyhydroxy-functional polyolefins, polyisobutylenes, polyisoprenes; polyhydroxy-functional ethylene / propylene, ethylene / butylene or ethylene / propylene / diene copolymers, such as those produced, for example, by Kraton Polymers; polyhydroxy-functional polymers of dienes, in particular 1,3-butadiene, which may also be prepared in particular by anionic polymerization; polyhydroxy-functional copolymers of dienes, such as 1,3-butadiene or mixtures of dienes, with vinyl monomers, such as styrene, acrylonitrile, vinyl chloride, vinyl acetate, vinyl alcohol, isobutylene or isoprene, in particular polyhydroxy-functional acrylonitrile / butadiene copolymers, which may be prepared in particular from epoxides or amino alcohols and carboxyl-terminated acrylonitrile / butadiene copolymers (commercially available, for example, under the name Hypro® CTBN or CTBNX or ETBN from Emerald Performance Materials); or hydrogenated polyhydroxy-functional polymers or copolymers of dienes.

[0095] Mixtures of polyols are also particularly suitable.

[0096] Preference is given to polyether polyols, polyester polyols, polycarbonate polyols, poly(meth)acrylate polyols or polybutadiene polyols.

[0097] Particular preference is given to polyether polyols, polyester polyols, especially aliphatic polyester polyols, or polycarbonate polyols, especially aliphatic polycarbonate polyols.

[0098] Particularly preferred are the polyether polyols, especially the polyoxyalkylene polyols.

[0099] Most preferred are polyoxypropylene di- or triols or ethylene oxide terminated polyoxypropylene di- or triols.

[0100] Preference is given to polyols with an average molecular weight Mn in the range from 400 to 20,000 g / mol, preferably from 1,000 to 15,000 g / mol.

[0101] Preference is given to polyols having an average OH functionality in the range from 1.6 to 3.

[0102] Preference is given to polyols which are liquid at room temperature.

[0103] In the preparation of polymers containing isocyanate groups, difunctional or polyfunctional alcohol fractions are used, in particular ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2-methylolpropane-1,3-diol, butane-1,2-diol, butane-1,3-diol, butane-1,4-diol, pentane-1,3-diol, pentane-1,5-diol, 3-methylpentane-1,5-diol, neopentyl glycol, dibromoneopentyl glycol, hexane-1,2-diol, hexane-1,6-diol, heptane-1,7-diol, octane-1,2-diol, octane-1,8-diol, 2-ethylhexane- It is also possible to use 1,3-diols, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexane-1,3- or -1,4-dimethanol, ethoxylated bisphenol A, propoxylated bisphenol A, cyclohexanediol, hydrogenated bisphenol A, dimeric fatty acid alcohols, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol, pentaerythritol, sugar alcohols (such as in particular xylitol, sorbitol or mannitol) or sugars (such as in particular sucrose) or alkoxylated derivatives of the alcohols mentioned or mixtures of the alcohols mentioned.

[0104] Preference is given in particular to the combination of one or more polyisocyanates with one or more polymers containing isocyanate groups.

[0105] For use in hot melt adhesives, isocyanate group-containing polymers that are solid at room temperature are preferred, which are prepared starting from at least one polyol that is solid at room temperature and a diisocyanate, in particular MDI. Suitable polyols that are solid at room temperature are crystalline, partially crystalline or amorphous at room temperature. Their melting point is preferably in the range from 50 to 180°C, in particular from 70 to 150°C. Preference is given to polyester polyols, in particular those derived from hexanediol and adipic acid or dodecanedicarboxylic acid, or acrylate polyols.

[0106] The latent hardener preferably contains at least one group selected from aldimino, ketimino, enamino and oxazolidino groups and at least one further group selected from hydroxyl groups, primary and secondary amino groups, aldimino, ketimino, enamino and oxazolidino groups.

[0107] Latent hardeners containing hydroxyl groups or primary or secondary amino groups are particularly suitable for two-part or multi-part compositions. When they are used in one-part compositions, they react when mixed with isocyanates to form reaction products with aldimino, ketimino, enamino or oxazolidino groups. Here, it is possible to reduce the content of monomeric diisocyanates in polymers containing isocyanate groups, which is advantageous for toxicological reasons.

[0108] The latent hardener more preferably contains two or three reactive groups selected from aldimino and oxazolidino groups. Such latent hardeners are particularly suitable for one-part compositions.

[0109] Preference is given to di- or triaryl dimines or bisoxazolidines.

[0110] Suitable bisoxazolidines are in particular those of the formula [ka] in which D is a divalent hydrocarbyl group having 6 to 15 carbon atoms, in particular 1,6-hexamethylene or (1,5,5-trimethylcyclohexan-1-yl)methane-1,3 or 4(2)-methyl-1,3-phenylene; and E is an organic radical having 3 to 30 carbon atoms, in particular 2-propyl, or 3-heptyl, or phenyl, or alkyl-substituted phenyl, in particular 4-decylphenyl, 4-undecylphenyl, 4-dodecylphenyl, 4-tridecylphenyl or 4-tetradecylphenyl, the 4-alkyl radicals being predominantly in branched form. It is a compound of the formula:

[0111] The latent hardener preferably has the formula [ka] (wherein y is 2 or 3, A is an organic group having 2 to 23 carbon atoms, and B is an organic group having 6 to 30 carbon atoms). is an aldimine.

[0112] A is preferably an alkylene group, optionally having a cyclic moiety, or a divalent or trivalent polyoxyalkylene group having 5 to 15 carbon atoms, in particular 1,6-hexylene, (1,5,5-trimethylcyclohexan-1-yl)methane-1,3 having an average molecular weight Mn in the range of 170 to 300 g / mol, or α,ω-polyoxypropylene, or tris(ω-polyoxypropylene) starting from trimethylolpropane having an average molecular weight Mn in the range of 330 to 500 g / mol.

[0113] B is preferably an organic group having 7 to 22 carbon atoms, in particular 2,2-dimethyl-3-acetoxypropylidene, 2,2-dimethyl-3-lauroyloxypropylidene, 2,2-dimethyl-3-(N-morpholino)propylidene, benzylidene or alkyl-substituted benzylidene, in particular 4-decylbenzylidene, 4-undecylbenzylidene, 4-dodecylbenzylidene, 4-tridecylbenzylidene or 4-tetradecylbenzylidene, in which the 4-alkyl group is predominantly branched.

[0114] More preferably, B is a group having at least 15 carbon atoms, especially 2,2-dimethyl-3-lauroyloxypropylidene or an alkyl-substituted benzylidene. Such aldimines are odorless.

[0115] formula [ka] Aldimines of the formula A-(NH 2 ) y with an aldehyde of formula O=B.

[0116] Preferred amines A-(NH 2 ) y are aliphatic or cycloaliphatic primary diamines or triamines, in particular hexamethylene-1,6-diamine, isophorone diamine, α,ω-polyoxypropylene diamines having an average molecular weight Mn in the range of 200 to 350 g / mol, in particular Jeffamine® D-230 (from Huntsman Corp.) or tris(ω-polyoxypropylene amines) starting from trimethylolpropane, in particular Jeffamine® T-403 (from Huntsman Corp.).

[0117] Preferred aldehydes O=B are aldol esters of carboxylic acids, in particular 2,2-dimethyl-3-acetoxypropanal, 2,2-dimethyl-3-lauroyloxypropanal, 2,2-dimethyl-3-(N-morpholino)propanal, benzaldehyde or benzaldehydes substituted by alkyl groups, in particular 4-decylbenzaldehyde, 4-undecylbenzaldehyde, 4-dodecylbenzaldehyde, 4-tridecylbenzaldehyde or 4-tetradecylbenzaldehyde, in which the 4-alkyl group is predominantly branched, and mixtures of these benzaldehydes substituted by alkyl groups.

[0118] Upon exposure to moisture, the latent hardener releases amino groups and possibly hydroxyl groups, which react with isocyanates and act as crosslinkers, thereby releasing aldehydes or ketones.

[0119] In the case of the preferred aldehydes of formula O=B, where B is a long-chain group, especially a group having 15 or more carbon atoms, it does not cause odor problems, remains in the composition after curing, has excellent compatibility and functions as a plasticizer.

[0120] Compared to the direct reaction of water with isocyanates, crosslinking with latent hardeners is 2 This has the advantage that it does not release ions and the tendency for blistering during curing is greatly reduced.

[0121] The composition preferably contains an amount of latent hardener such that the ratio between the number of reactive groups releasable therefrom and the number of isocyanate groups ranges from 0.1 to 1.5, preferably from 0.2 to 1.1, in particular from 0.3 to 1.0.

[0122] The curable composition preferably further comprises one or more further components selected in particular from plasticizers, fillers and catalysts for the reaction of isocyanate groups.

[0123] Suitable plasticizers are, in particular, phthalates, in particular diisononyl phthalate (DINP), diisodecyl phthalate (DIDP) or di(2-propylheptyl) phthalate (DPHP), hydrogenated phthalates or cyclohexane-1,2-dicarboxylates, in particular hydrogenated diisononyl phthalate or diisononyl cyclohexane-1,2-dicarboxylate (DINCH), terephthalates, in particular bis(2-ethylhexyl) terephthalate (DOTP) or diisononyl terephthalate (DINT), hydrogenated terephthalates or cyclohexane-1,4-dicarboxylates, in particular hydrogenated bis(2-ethylhexyl) terephthalate or bis(2-ethylhexyl) terephthalate (DOTP). cyclohexane-1,4-dicarboxylate or hydrogenated diisononyl terephthalate or diisononyl cyclohexane-1,4-dicarboxylate, carboxylic acid esters such as isophthalates, trimellitates, adipates, especially dioctyl adipate, azelates, sebacates, benzoates, glycol ethers, glycol esters, plasticizers having a polyether structure, especially the polyethers described herein having blocked hydroxyl groups, organic phosphates or sulfonates, polybutenes, polyisobutenes or plasticizers derived from natural fats and oils, especially epoxidized soybean oil or linseed oil.

[0124] Preferred plasticizers are diisononyl phthalate, diisodecyl phthalate or polyethers having blocked hydroxyl groups as described herein.

[0125] Suitable fillers are in particular ground or precipitated calcium carbonate, barite, quartz flour, quartz sand, dolomite, wollastonite, calcined kaolin, layered silicates such as mica or talc, zeolites, aluminium hydroxide, magnesium hydroxide, silica (including finely divided silica from pyrolysis processes), cement, gypsum, fly ash, industrially produced carbon black, graphite, metal powders such as aluminium, copper, iron, silver or steel, PVC powder or hollow beads, which can optionally be coated with fatty acids (especially stearic acid esters).

[0126] Preference is given to calcium carbonate, calcined kaolin or industrially produced carbon black, which may optionally be coated with fatty acids (especially stearic acid esters).

[0127] Suitable catalysts for promoting the reaction of isocyanate groups are, in particular, organotin(IV) compounds such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, dibutyltin diacetylacetonate, dimethyltin dilaurate, dioctyltin diacetate, dioctyltin dilaurate or dioctyltin diacetylacetonate; complexes of bismuth(III) or zirconium(IV), in particular with ligands selected from alkoxides, carboxylates, 1,3-diketonates, oxinates, 1,3-ketoesterates and 1,3-ketoamidates; or compounds containing tertiary amino groups, in particular 2,2′-dimorpholinodiethyl ether (DMDEE).

[0128] The curable composition may contain further additives, in particular: - inorganic or organic pigments, in particular titanium dioxide, chromium oxide or iron oxide; - fibres, in particular glass, carbon, metal, ceramic, polymer (such as polyamide or polyethylene) or natural fibres (such as wool, cellulose, hemp or sisal); - nanofillers such as graphene or carbon nanotubes; - dye; - desiccants, in particular molecular sieve powders, calcium oxide, highly reactive isocyanates such as p-tosylisocyanate, monooxazolidines or orthoformates such as Incozol® 2 (from Incorez); adhesion promoters, in particular organic alkoxysilanes, in particular epoxysilanes, such as 3-glycidoxypropyltrimethoxysilane or 3-glycidoxypropyltriethoxysilane, (meth)acrylosilanes, anhydridosilanes, carbamatosilanes, alkylsilanes or iminosilanes or oligomeric forms of these silanes or titanates; - additional catalysts which accelerate the reaction of isocyanate groups, in particular salts, soaps or complexes of tin(II), zinc, iron, aluminium, molybdenum, dioxomolybdenum, titanium or potassium, in particular tin(II) 2-ethylhexanoate, tin(II) neodecanoate, zinc(II) acetate, zinc(II) 2-ethylhexanoate, zinc(II) laurate, zinc(II) acetylacetonate, aluminium lactate, aluminium oleate, diisopropoxytitanium bis(ethylacetoacetate) or potassium acetate; compounds containing tertiary amino groups, in particular N-ethyldiisopropylamine, N,N,N',N'-tetramethylalkylenediamines, pentamethylalkylenetriamines and their higher analogues. bis(N,N-diethylaminoethyl)adipate, tris(3-dimethylaminopropyl)amine, 1,4-diazabicyclo[2.2.2]octane (DABCO), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), N-alkylmorpholines, N,N'-dimethylpiperazines; aromatic nitrogen compounds such as 4-dimethylaminopyridine, N-methylimidazole, N-vinylimidazole or 1,2-dimethylimidazole; organic ammonium compounds such as benzyltrimethylammonium hydroxide or alkoxylated tertiary amines; and the so-called "delayed action" catalysts, which are modifications of known metal or amine catalysts; - rheology modifiers, in particular thickeners, in particular layered silicates such as bentonite, derivatives of castor oil, hydrogenated castor oil, polyamides, polyamide waxes, polyurethanes, urea compounds, fumed silica, cellulose ethers or hydrophobically modified polyoxyethylene; solvents, in particular acetone, methyl acetate, tert-butyl acetate, 1-methoxy-2-propyl acetate, ethyl 3-ethoxypropionate, diisopropyl ether, diethylene glycol diethyl ether, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, ethylene glycol mono-2-ethylhexyl ether, acetals (such as propylal, butyral, 2-ethylhexylal, dioxolane, glycerol formal or 2,5,7,10-tetraoxaundecane (TOU)), toluene, xylene, heptane, octane, naphtha, white spirit, petroleum ether or gasoline, in particular Solvesso TM grades (from ExxonMobil Chemical Co.) and propylene carbonate, dimethyl carbonate, butyrolactone, N-methylpyrrolidone, N-ethylpyrrolidone, p-chlorobenzotrifluoride or benzotrifluoride; - natural resins, oils and fats, such as rosin, shellac, linseed oil, castor oil or soybean oil; - non-reactive polymers, in particular homopolymers or copolymers of unsaturated monomers, in particular those selected from the group comprising ethylene, propylene, butylene, isobutylene, isoprene, vinyl acetate or alkyl (meth)acrylates, in particular polyethylene (PE), polypropylene (PP), polyisobutylene, ethylene / vinyl acetate copolymers (EVA) or atactic poly-α-olefins (APAO); - flame-retardant substances, in particular the aforementioned aluminium hydroxide or magnesium hydroxide fillers and in particular organic phosphates, such as in particular triethyl phosphate, tricresyl phosphate, triphenyl phosphate, diphenyl cresyl phosphate, isodecyl diphenyl phosphate, tris(1,3-dichloro-2-propyl) phosphate, tris(2-chloroethyl) phosphate, tris(2-ethylhexyl) phosphate, tris(chloroisopropyl) phosphate, tris(chloropropyl) phosphate, isopropylated triphenyl phosphate, mono-, bis- or tris(isopropylphenyl) phosphates of various degrees of isopropylation, resorcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate) or ammonium polyphosphate; additives, in particular wetting agents, levelling agents, defoamers, degassing agents, stabilisers against oxidation, heat, light or UV light or biocides; or Further substances commonly used in curable compositions.

[0129] It may be desirable to chemically or physically dry certain materials before incorporating them into the composition.

[0130] The curable composition preferably comprises - 10% to 70% by weight, in particular 20% to 50% by weight, of a polymer containing isocyanate groups, - 0.1% to 20% by weight, in particular 1% to 15% by weight, of a latent hardener, - 20% to 60% by weight of a filler, - 5% to 40% by weight of a plasticizer, and - 0.01% to 0.5% by weight, in particular 0.02% to 0.25% by weight, of an aromatic carboxylic acid or sulfonic acid dissolved in a polyether having blocked hydroxyl groups. Includes.

[0131] Optionally, the polyether having blocked hydroxyl groups may also be present at least in part as a plasticizer in the hardenable composition.

[0132] The curable composition is in particular prepared with the exclusion of moisture and stored at ambient temperature in a moisture-proof container, suitable moisture-proof containers being in particular made of optionally coated metal and / or plastic, in particular drums, transport boxes, pails, buckets, canisters, tins, bags, tubular bags, cartridges or tubes.

[0133] The curable compositions may be in the form of a one-part composition or may be multi-part, especially two-part, compositions.

[0134] The curable composition is preferably a one-part moisture-curable composition, which, when properly packaged and stored, is shelf stable, typically for several months up to a year or more.

[0135] In one embodiment, the curable composition has two components, a first component containing at least one polyol and a second component comprising at least one polyisocyanate and optionally at least one isocyanate group-containing polymer. The latent curing agent or the acid solution described herein may be present in one or both of the two components, respectively. Suitable polyols are the polyols mentioned above, in particular for the preparation of the polymer containing isocyanate groups.

[0136] Once the curable composition is applied, the curing process begins.

[0137] In the case of a one-part moisture-curable composition, it is applied as is and then begins to cure under the influence of moisture or water. To accelerate the cure, accelerator components that contain or release water and / or catalysts can be mixed into the composition at the time of application, or the composition can be contacted with such accelerator components after its application.

[0138] In the case of a two-part composition, the two components are mixed and then applied, and hardening begins by an internal reaction, and hardening can be completed by the action of external moisture. The two components can be mixed continuously or in batches using dynamic or static mixers.

[0139] During the curing process, the isocyanate groups present react with each other under the influence of moisture and / or with any additional reactive groups present in the composition, in particular hydroxyl or amino groups. Furthermore, the isocyanate groups react with the reactive groups of the latent hardeners present as they are hydrolyzed.

[0140] The acid solution present in the composition accelerates the hydrolysis, especially of the latent hardener, and promotes rapid and blister-free curing.

[0141] The moisture required for the curing of moisture-curable compositions preferably enters the composition by diffusion from the air (air humidity). In the process, a solid layer (skin) of the cured composition is formed on the surface of the composition in contact with the air. As the curing continues in the direction of diffusion from the outside to the inside, the skin becomes thicker and thicker, eventually surrounding the entire applied composition. Moisture can also enter the composition additionally or completely from one or more substrates to which the composition is applied, and / or may come from accelerator components that are mixed into the composition during application or that come into contact with it after application, for example by painting or spraying.

[0142] The curable composition is preferably applied at ambient temperature, especially in the range of about -10 to 50°C, preferably in the range of -5 to 45°C, especially 0 to 40°C.

[0143] The composition is preferably similarly cured at ambient temperature.

[0144] The compositions are suitable for a variety of applications.

[0145] The composition is preferably an adhesive, or a sealant, or a coating.

[0146] The adhesive, sealant, or coating is preferably elastic.

[0147] The curable polyurethane compositions as adhesives and / or sealants are particularly suitable for bonding and sealing applications in construction and manufacturing or in automotive assembly, in particular for parquet bonding, assembly, bonding of attachable parts, bonding of modules, bonding of glazing, sealing of joints, sealing of car bodies, seam sealing or sealing of cavities.

[0148] Elastic bonding in automotive construction is, for example, the adhesive attachment of parts such as plastic covers, trim strips, flanges, fenders, cabs or other attachable components to the painted body of a motor vehicle, particularly a car, truck, bus, rail car or watercraft, or the bonding of window glass to a vehicle body.

[0149] The curable polyurethane compositions as sealants are particularly suitable for the elastic sealing of any kind of joints, seams or cavities, in particular structural joints such as expansion joints or bonded joints between components or floor joints in civil engineering.

[0150] The curable polyurethane compositions as coatings are particularly suitable for protecting and / or sealing building structures or parts thereof, in particular for balconies, terraces, roofs, especially flat roofs or slightly sloping roof areas, or roof gardens, or in building interiors such as wet rooms, or kitchen floor tiles, or ceramic plates, or in collection pans, conduits, shafts, silos, tanks or wastewater treatment systems.

[0151] For example, it may be used for repair purposes as a seal or coating on leaking roof membranes or floor coverings that have become unfit for purpose, or as a highly reactive spray seal repair compound.

[0152] The curable composition can be formulated to have a high yield point and a paste-like consistency, especially for use as an adhesive or sealant. Such a composition can be applied under pressure with a spatula or a suitable device, for example a cartridge gun, or a drum pump, or an application robot, and the composition is especially released in the form of a bead having an essentially circular or triangular cross-sectional area.

[0153] The curable composition can also be formulated to be flowable and "self-leveling" or only slightly thixotropic, especially for use as a sealing compound or coating. Such a composition can be applied by pouring it or with a spatula. It can then be distributed over the area in the form of a coating, for example with a roller, doctor blade, trowel or rubber squeegee, to obtain the desired thickness. In one operation, a layer thickness in the range of 0.5 to 5 mm, especially 1 to 3 mm, is typically applied.

[0154] Suitable substrates which can be bonded or sealed or coated with the curable composition are in particular - glass, glass ceramics, concrete, mortar, cement screed, fibre cement, in particular fibre cement boards, bricks, tiles, gypsum, in particular gypsum boards or anhydrous screeds or natural stone, such as granite or marble; - Repair or levelling compounds based on PCC (polymer modified cement mortar) or ECC (epoxy resin modified cement mortar); - Metals or alloys such as aluminium, copper, iron, steel, non-ferrous metals, including metals or alloys with a surface finish such as galvanised or chrome-plated metals; - Asphalt or bitumen; - leather, textiles, paper, wood, wood bonded with resins (such as phenolic, melamine or epoxy resins), further materials called resin / textile composites or polymer composites; - plastics such as rigid and flexible PVC, polycarbonate, polystyrene, polyester, polyamide, PMMA, ABS, SAN, epoxy resins, phenolic resins, PUR, POM, TPO, PE, PP, EPM or EPDM, in each case untreated or surface-treated, for example by plasma, corona or flame; - Fiber reinforced plastics such as Carbon Fiber Reinforced Plastics (CFP), Glass Fiber Reinforced Plastics (GFP) and Sheet Moulding Compounds (SMC); - Thermal insulation foams, in particular those made of EPS, XPS, PUR, PIR, rock wool, glass wool or foam glass; - Coated or painted substrates, in particular painted tiles, coated concrete, powder-coated metals or alloys or painted metal sheets; - Paints or varnishes, especially automotive topcoats It is.

[0155] If necessary, the substrate can be pretreated before application, especially by physical and / or chemical cleaning methods or by application of an activator or primer.

[0156] It is possible to bond and / or seal the same or different substrates.

[0157] Application and curing of the curable composition results in an article.

[0158] Thus, the present invention further provides articles bonded or sealed or coated with the compositions described herein.

[0159] The article may in particular be an above-ground or underground architectural structure or part thereof, in particular a bridge, a roof, a staircase or a facade, or it is an industrial or consumer product, in particular a window, a pipe, a rotor blade of a wind turbine, a household appliance or a means of transport (in particular a car, bus, truck, rail vehicle, ship, aircraft or helicopter) or an attachable component thereof.

[0160] The hardenable composition has advantageous properties: it is very easy to manufacture, especially because of the low concentration of the acid solution of the present invention, which allows for high acid concentrations, it cures quickly, does not blister, does not emit odors or emissions, and after curing, it shows few migration-related drawbacks such as leaching or staining, due to the excellent compatibility of the acid solution. EXAMPLES

[0161] In the following, examples are presented that are intended to clarify the invention as described. It will be understood that the invention is not limited to these described examples.

[0162] "Standard Climatic Conditions" ("SCC") refers to a temperature of 23±1°C and a relative humidity of air of 50±5%.

[0163] Unless otherwise stated, chemicals used were from Sigma-Aldrich Chemie GmbH.

[0164] Commercially available plasticizers used: DIDP: Diisodecyl phthalate (Palatinol® 10-P, from BASF SE) DOA: di(2-ethylhexyl) adipate (Plastomoll® DOA, from BASF SE) SPX-80: Branched polyether polyol with esterified hydroxyl groups, average molecular weight about 5,000 g / mol (Sanflex® SPX-80, from Sanyo Chem. Ind.)

[0165] Preparation of polyethers with blocked hydroxyl groups: Viscosity was measured using a thermostated Rheotec RC30 cone-plate viscometer (cone diameter 25 mm, cone angle 1°, cone tip-plate distance 0.05 mm, shear rate 10 s -1 ) was measured.

[0166] Infrared spectra (FT-IR) were measured as undiluted films on a Thermo Scientific Nicolet iS5 FT-IR instrument equipped with a horizontal ATR measurement unit with a diamond crystal. Absorption bands are expressed in wavenumbers (cm -1 ) has been reported.

[0167] 1 H NMR spectra were recorded on a Bruker Ascend 400 type spectrometer at 400.14 MHz. Chemical shifts δ are reported in ppm relative to tetramethylsilane (TMS). True and spurious coupling patterns could not be distinguished.

[0168] Polyether-1: Acetylated PPG monool with an average molecular weight of about 800 g / mol, starting from n-butanol 120.00 g of n-butanol-based polyoxypropylene monol (Synalox® 100-20B, average molecular weight approximately 750 g / mol; from DowDuPont Inc.) and 18.74 g of acetic anhydride were initially placed in a round-bottom flask equipped with a distillation attachment under nitrogen atmosphere. The reaction mixture was then stirred under a gentle stream of nitrogen at 130° C. while acetic acid was collected as a distillate. Volatile components were subsequently removed from the reaction mixture at 80° C. and a reduced pressure of 10 mbar. A clear, colorless liquid with a viscosity of 75 mPa·s at 20° C. was obtained.

[0169] FT-IR:2970,2931,2867,1738,1454,1372,1345,1296,1241,1098,1014,959,925,866,827.

[0170] 1 H NMR (CDCl 3 ):5.02(hept.,1H,CH 2 (CH 3 )CH-OAc),3.75-3.34(2xm, approx. 39H, OCH 2 CH(CH 3 )O),3.33-3.28(m,2H,CH3 CH 2 CH 2 CH 2 O), 2.04(s, 3H, O(CO)CH 3 ), 1.55(quint., 2H, CH 3 CH 2 CH 2 CH 2 O), 1.36(sext., 2H, CH 3 CH 2 CH 2 CH 2 O), 1.22(d,3H,CH 2 (CH 3 )CH-OAc),1.17-1.10(m, approx. 36H, OCH 2 CH(CH 3 )O),0.91(t,3H,CH 3 CH 2 CH 2 CH 2 O).

[0171] Polyether-2: Acetylated PPG monool with an average molecular weight of about 1,150 g / mol, starting from n-butanol Starting from 176.00 g of n-butanol, polyoxypropylene monol (Synalox® 100-40B, average molecular weight approximately 1,100 g / mol; from DowDuPont Inc.) and 18.74 g of acetic anhydride, was converted as described for polyether-1. A clear, colorless liquid with a viscosity of 140 mPa·s at 20°C was obtained.

[0172] Polyether-3: Acetylated PPG monool with an average molecular weight of about 1,850 g / mol, starting from n-butanol Starting from 288.00 g of n-butanol, polyoxypropylene monol (Synalox® 100-85B, average molecular weight approximately 1,800 g / mol; from DowDuPont Inc.) and 18.74 g of acetic anhydride, was converted as described for polyether-1. A clear, colorless liquid with a viscosity of 350 mPa·s at 20°C was obtained.

[0173] Polyether-4: Diacetylated PPG diol with an average molecular weight of approximately 800 g / mol 58.00 g of polyoxypropylene diol (polypropylene glycol, average molecular weight approximately 725 g / mol; from Sigma Aldrich Chemie GmbH) and 18.74 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 100 mPa·s at 20 °C was obtained.

[0174] Polyether-5: Diacetylated PPG diol with an average molecular weight of approximately 1,100 g / mol 80.00 g of polyoxypropylene diol (Voranol® P1010, OH value 110 mg KOH / g; from DowDuPont Inc.) and 18.74 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 145 mPa·s at 20° C. was obtained.

[0175] Polyether-6: A diacetylated PPG diol with an average molecular weight of approximately 2,100 g / mol. 160.00 g of polyoxypropylene diol (Voranol® P2000L, OH value 56 mg KOH / g; from DowDuPont Inc.) and 18.74 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 400 mPa·s at 20° C. was obtained.

[0176] Polyether-7: Diacetylated PPG diol with an average molecular weight of approximately 4,100 g / mol 600.0 g of polyoxypropylene diol (Acclaim® 4200, OH value 28 mg KOH / g; from Covestro AG) and 33.7 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 1,150 mPa·s at 20 °C was obtained.

[0177] Polyether-8: Diacetylated PPG diol with an average molecular weight of approximately 8,100 g / mol 600.0 g of polyoxypropylene diol (Acclaim® 8200, OH value 14 mg KOH / g; from Covestro AG) and 16.8 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 3,800 mPa·s at 20° C. was obtained.

[0178] Polyether-9: Triacetylated PPG triol with an average molecular weight of approximately 850 g / mol 74.40 g of polyoxypropylenethiol (Desmophen® 28HS98, OH value 230 mg KOH / g; from Covestro AG) and 37.48 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 135 mPa·s at 20 °C was obtained.

[0179] Polyether-10: Triacetylated PPG triol with an average molecular weight of approximately 1650 g / mol 80.00 g of polyoxypropylenethiol (Arcol® LHT-112, OH value 112 mg KOH / g; from Covestro AG) and 18.74 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 285 mPa·s at 20 °C was obtained.

[0180] Polyether-11: Triacetylated PPG triol with an average molecular weight of approximately 3150 g / mol 160.00 g of polyoxypropylenethiol (Desmophen® 3061BT, OH value 56 mg KOH / g; from Covestro AG) and 18.74 g of acetic anhydride were converted as described for polyether-1. A clear, colorless liquid with a viscosity of 575 mPa·s at 20 °C was obtained.

[0181] Preparation of acid solution: Solution L-1~L-24 To an initial charge of 5 g of the solvent specified in Table 1 in a vial, sufficient salicylic acid or 2-nitrobenzoic acid was added to a concentration of 2.0%, or 4.8%, or 9.1%, or 13.0%, or 16.7%, or 20.0%, or 23.1% by weight of the acid (100% = acid + solvent), and the mixture was heated to 80°C in an air-circulating oven. An attempt was then made in each case to completely dissolve the acid by stirring. If this was possible, the solution was then stored for 7 days in an air-circulating oven at 50°C, then for a further 7 days at 23°C, and finally for a further 7 days in a refrigerator at 4°C, and in each case an evaluation was made as to whether the acid had crystallized out of the solution at the end of the storage times at 50°C, 23°C and 4°C. The maximum stable concentration refers to the concentration of the solution at which no crystallization of the acid was observed within 7 days at 4°C.

[0182] The results are reported in Table 1.

[0183] The examples marked with "(Ref.)" are comparative examples.

[0184] [Table 1]

[0185] Solution L-25~L-38 In each case, a 10% acid solution was prepared by dissolving 1.0 g of the acid specified in Table 2 in 9.0 g of the solvent specified in Table 2 and storing the solution in a closed container.

[0186] The viscosity of each solution at 20° C. was measured as described above.

[0187] The results are reported in Table 2.

[0188] [Table 2]

[0189] Preparation of the curable (one-part) composition: Polymer P1: 400 g of polyoxypropylene diol (Acclaim® 4200 from Covestro AG; OH number 28.5 mg KOH / g) and 52 g of diphenylmethane 4,4′-diisocyanate (Desmodur® 44MCL from Covestro AG) were reacted in a known manner at 80° C. to give an NCO-terminated polymer which was liquid at room temperature and had a content of isocyanate groups of 1.85% by weight.

[0190] Polymer P2: 1,300 g of polyoxypropylene diol (Acclaim® 4200 from Covestro AG; OH value 28 mg KOH / g), 2,600 g of ethylene oxide-terminated polyoxypropylene triol (Voranol® CP4755 from DowDuPont Inc.; OH value 35 mg KOH / g), 600 g of diphenylmethane 4,4'-diisocyanate (Desmodur® 44MCL from Covestro AG) and 500 g of diisodecyl phthalate were reacted at 80°C in a known manner to give an NCO-terminated polymer which was liquid at room temperature and had a content of isocyanate groups of 2.05% by weight.

[0191] Aldimine-1: N,N'-bis(2,2-dimethyl-3-lauroyloxypropylidene)-3-aminomethyl-3,5,5-trimethylcyclohexylamine (= latent hardener) 598g (2.1mol) of 2,2-dimethyl-3-lauroyloxypropanal is first placed in a round-bottom flask under nitrogen atmosphere.Then, 170.3g (1mol) of 3-aminomethyl-3,5,5-trimethylcyclohexylamine (Vestamin® IPD, from Evonik Industries AG) is added with good stirring, and then volatile components are removed under reduced pressure at 80°C and 10mbar.732g of colorless liquid is obtained with an amine content of 2.73mmol N / g, which corresponds to a calculated aldimine equivalent of 367g / mol.

[0192] Compositions Z1~Z9 For each composition, the components specified in Tables 3-4 were mixed in the specified amounts (parts by weight) using a centrifugal mixer (SpeedMixer™ DAC150, FlackTek Inc.) at 3000 rpm for 1 minute while excluding moisture, and then stored with the moisture excluded.

[0193] Each composition was tested as follows.

[0194] Viscosity was measured at the specified temperatures using a thermostated Rheotec RC30 cone-plate viscometer (cone diameter 25 mm, cone angle 1°, cone tip-plate distance 0.05 mm) at 0°C for 5s. -1 At a shear rate of 10 s for measurements at 10°C, 20°C and 30°C, -1 The measurements were performed at a shear rate of .

[0195] Each composition was tested as follows: The skin time (ST) was determined as a measure of the open time. For this purpose, a few grams of the composition were applied to a cardboard board in a layer thickness of about 2 mm and the first time was determined at which, under standard climatic conditions, no residues were left on an LDPE pipette used to gently tap the surface of the composition.

[0196] The Shore A hardness was determined according to DIN 53505 on test specimens cured for 14 days under standard climatic conditions.

[0197] To determine the mechanical properties, the composition was applied to a PTFE-coated film to obtain a film of 2 mm thickness, which was then stored under standard climatic conditions for 14 days, and several dumbbells of 75 mm length with a bar length of 30 mm and a bar width of 4 mm were punched out of the film and tested according to DIN EN53504 for tensile strength (breaking load), elongation at break, modulus of elasticity 5% (elongation from 0.5% to 5%) and modulus of elasticity 25% (elongation from 0.5% to 25%) at a strain rate of 200 mm / min.

[0198] The appearance of the produced films was visually evaluated, with "good" being used to indicate a tack-free film with no blistering.

[0199] Odor was assessed by sniffing the freshly produced film with the nose at a distance of 2 cm. "None" means that no odor was perceived.

[0200] The results are reported in Tables 3-4.

[0201] [Table 3]

[0202] [Table 4]

Claims

1. Use of at least one polyether having blocked hydroxyl groups as a solvent for at least one aromatic carboxylic or sulfonic acid.

2. 2. The use according to claim 1, characterized in that the blocked hydroxyl groups are selected from the group consisting of ester groups, acetoester groups, carbonate groups and urethane groups.

3. 3. The use according to claim 1 or 2, characterized in that the blocked hydroxyl group is an acetate group.

4. 4. Use according to any one of claims 1 to 3, characterized in that from 70% to 100% by weight of the repeating units in the polyether consist of 1,2-propyleneoxy groups and from 0% to 30% by weight of the repeating units in the polyether consist of 1,2-ethyleneoxy groups.

5. The blocked hydroxyl group-containing polyethers have average molecular weights M ranging from 600 to 10,000 g / mol, as determined by gel permeation chromatography (GPC) against polystyrene as standard, using tetrahydrofuran as the mobile phase, a refractive index detector, and an evaluation from 200 g / mol. ｎ Use according to any one of claims 1 to 4, characterized in that it has

6. Use according to any one of claims 1 to 5, characterized in that the polyether having blocked hydroxyl groups is derived from at least one hydroxy-functional polyether selected from the group consisting of: polyoxypropylene monols starting from alcohols, in particular starting from n-butanol, having an OH number in the range from 25 to 90 mg KOH / g; - polyoxypropylene diols having an OH number ranging from 12 to 155 mg KOH / g, - polyoxypropylene triols, optionally ethylene oxide terminated, starting from trimethylolpropane or especially glycerol, having an average OH functionality in the range from 2.2 to 3 and an OH number in the range from 22 to 230 mg KOH / g, and Polyoxypropylene polyols starting from sugar alcohols, in particular starting from threitol, erythritol, xylitol, mannitol or sorbitol, and having an average OH functionality ranging from 3 to 6.

7. Use according to any one of claims 1 to 6, characterized in that the aromatic carboxylic or sulfonic acid is selected from the group consisting of benzoic acid, 2-nitrobenzoic acid, salicylic acid and p-toluenesulfonic acid.

8. An acid solution resulting from the use according to any one of claims 1 to 7.

9. 9. The acid solution according to claim 8, characterized in that from 2.5% to 25% by weight of aromatic carboxylic or sulfonic acid and from 50% to 97.5% by weight of polyether with blocked hydroxyl groups are present.

10. A hardenable composition comprising the acid solution according to claim 8 or 9.

11. The curable composition of claim 10, comprising: at least one polyisocyanate or polymer containing isocyanate groups, at least one latent hardener containing at least one aldimino, ketimino, enamino or oxazolidino group, at least one polyether having blocked hydroxyl groups, and at least one aromatic carboxylic or sulfonic acid;

12. The curable composition according to claim 11, characterized in that the latent curing agent is an aldimine of the following formula: 【Chemistry 1】 where y is 2 or 3, A is an organic group having 2 to 23 carbon atoms, and B is an organic group having 6 to 30 carbon atoms.

13. The curable composition according to claim 11 or 12, characterized in that it is a one-component moisture-curable composition.

14. The curable composition according to any one of claims 10 to 13, characterized in that it is an adhesive, a sealant or a coating.

15. An article bonded, sealed or coated with the curable composition of any one of claims 10 to 14.

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