Compositions based on renewable raw materials and their use in polyurethane applications

Abstract

The invention relates to compositions comprising a NCO-reactive component and a polyisocyanurate composition, which is obtainable from a mixture of diisocyanates of the general formula OCN-R-NCO, wherein R is a divalent linear or branched aliphatic residue containing at least 4 carbon atoms, and of sugar based polyisocyanates and which has a low content of residual monomeric isocyanates. Moreover, the invention relates to the use of these compositions in the synthesis of coatings, adhesives and sealants, to the coatings, adhesives and sealants themselves and to substrates comprising the inventive coating compositions or coatings.

Description

[0001] 2024PF30135-Foreign Countries

[0002] 1

[0003] Compositions based on renewable raw materials and their use in polyurethane applications The invention relates to compositions comprising an NCO-reactive component and a polyisocyanurate composition, which is obtainable from a mixture of diisocyanates of the general formula OCN-R-NCO, wherein R is a divalent linear or branched aliphatic residue containing at least 4 carbon atoms, and of sugar based diisocyanates and which has a low content of residual monomeric isocyanates. Moreover, the invention relates to the use of these compositions in the synthesis of coatings, adhesives and sealants, to the coatings, adhesives and sealants themselves and to substrates comprising the inventive coating compositions or coatings.

[0004] Monomeric diisocyanates are practically not used as crosslinkers in polyurethane systems due to their volatility and toxicological properties. Usually, higher molecular weight derivatives are used, modified for example with isocyanurate, iminooxadiazinedione, uretdione, urethane or allophanate groups. An overview of these polyisocyanates and their production method is exemplified in Laas et al., J. Prakt. Chem. 336, 1994, 185-200.

[0005] The oligomerization or polymerization of monomeric diisocyanates, especially to form higher molecular weight oligomer mixtures, has long been known. The reaction of a relatively small number of isocyanates with one another is referred to as oligomerization. The reaction of a relatively large number of isocyanates is referred to as polymerization. All products resulting from such processes are referred to collectively in this document as oligomeric / polymeric polyisocyanates.

[0006] Monomeric isocyanates formed from renewable raw materials and their higher molecular weight derivatives are playing an ever greater part not least, quite simply, for reasons of sustainability and also for reasons of cost.

[0007] This explains, inter alia, the development of diisocyanates based on renewable and inexpensive sugars, such as 1:4-3:6 dianhydrohexitols for example (J. Thiem et al., Macromol. Chem. Phys. 202, 3410-3419, 2001. WO2011 / 000587 describes the synthesis of higher molecular weight derivates of these diisocyanates, i.e. of (3R,3aR,6S,6aR)-, (3S,3aR,6S,6aR)- and (3R,3aR,6R,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan and WO2011 / 000586 and WO2011 / 000585 describe the use of these diisocyanates in polyurethane systems. Polyisocyanates based on mixtures of these sugar based diisocyanates with further aliphatic diisocyanates are not disclosed in these documents.

[0008] EP 4 296 260 discloses phosgenation of at least two different amines to obtain the corresponding isocyanates.

[0009] US 2012 / 0073472 and US 2012 / 0071577 disclose dianhydrohexitol-based diisocyanates and derivatives thereof. 2024PF30135-Foreign Countries

[0010] 2

[0011] It was an object of the present invention to provide compositions based on renewable raw materials, with short chemical and physical drying times, even at low temperatures and without using a catalyst. The latter is advantageous regarding industrial hygiene, since many of the catalysts commonly used in polyurethane chemistry are more or less toxic.

[0012] Moreover, it was an object of the present invention to provide compositions based on renewable raw materials, leading to coatings, adhesives and sealants with good mechanical properties, as e.g. a high pendulum hardness, and with a good chemical resistance.

[0013] These objects have been achieved by a composition comprising

[0014] A) a polyisocyanate composition comprising at least one isocyanurate structure and having a residual monomeric diisocyanate content of diisocyanates of components Al) and A2) of less than 1 % by weight, based on the total weight of the polyisocyanate composition, determined by gas chromatography in accordance with DIN EN ISO 10283:2007-11 with internal standard, obtainable or obtained by a process comprising

[0015] reacting an isocyanate composition, comprising

[0016] Al) (3R,3aR,6S,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan and / or (3S,3aR,6S,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan and / or (3R,3aR,6R,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan and

[0017] A2) at least one diisocyanate of the general formula OCN-R-NCO, wherein R is a divalent linear or branched aliphatic residue containing at least 4 carbon atoms, optionally in the presence of at least one catalyst A3), to form a raw polyisocyanate composition,

[0018] and subjecting the raw polyisocyanate composition to a distillation, preferably to a thin film distillation, a short path distillation and / or a falling film distillation, in order to at least partially remove unreacted moieties of components Al) and A2) and to obtain the polyisocyanate composition comprising at least one isocyanurate structure,

[0019] wherein the weight ratio of (3R,3aR,6S,6aR)-3,6-diyl-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-, (3S,3aR,6S,6aR)-3,6-diyl-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan- and / or (3R,3aR,6R,6aR)- 3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-structures in polyisocyanate composition A) to structures -R- in polyisocyanate composition A), wherein R corresponds to the organic residue R in the general formula OCN-R-NCO of component A2), is > 2.5:1 to < 2024PF30135-Foreign Countries

[0020] 3

[0021] 8:1, wherein the fraction of these structures in the polyisocyanate composition is determined using NMR spectroscopic analysis as defined in the description,

[0022] and

[0023] B) at least one NCO-reactive compound

[0024] wherein components A) and B) are used in amounts corresponding to an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 2: 1 to 0.5 to 1.

[0025] The references to "comprising", "containing", etc. preferably denote "substantially consisting of and very particularly preferably denote "consisting of. In the present invention, any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of „1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

[0026] Isocyanurate structures (also referred to as isocyanurate groups) are understood as structural units of the following general formula:

[0027]

[0028] Isocyanurate structure

[0029] Component A): polyisocyanate composition comprising at least one isocyanurate structure Isocyanate composition comprising components Al) and A2) and its reaction:

[0030] According to this invention, (3R,3aR,6S,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan is referred to “ISODI”, (3S,3aR,6S,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan is referred to “IDDI” and (3R,3aR,6R,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan is referred to “IMANDI”.

[0031] The precursors for the synthesis of ISODI and IDDI can be obtained from different sources but are preferably obtained from a biobased source.

[0032] Preferred diisocyantes of component A2) are diisocyanate of the general formula OCN-R-NCO, wherein R is a divalent linear or branched aliphatic residue containing 4 to 10 carbon atoms. Suitable diisocyanates are, for example: pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), 2-methylpentane 1,5 -diisocyanate, 2,2,4-trimethylhexane 1,6-diisocyanate, 2,4,4-trimethylhexane 1,6-diisocyanate and / or 4-isocyanatomethyloctane 1,8-diisocyanate. Preferred is the use of PDI and / or HDI. 2024PF30135-Foreign Countries

[0033] 4

[0034] Optionally the isocyanate composition may comprise further monomeric diisocyanates different from components Al) and A2). Preference is given to 3 (4)-isocyanatomethyl-l -methylcyclohexyl isocyanate (IMCI), isophorone diisocyanate (IPDI), 1,3- and l,4-bis(isocyanatomethyl)benzene (XDI) and / or 1,3-and l,4-bis(isocyanatomethyl)cyclohexane (H6XDI).

[0035] In a preferred embodiment of the invention, component Al) is used in amounts of >5 to < 95 % by weight, preferably > 10 to < 90 % by weight, more preferably > 20 to < 80 % by weight, in each case based on the total amount of components Al) and A2).

[0036] The amount of the optional further diisocyanates different from the essential diisocyanates of components Al) and A2) is guided by the specific application and, if they are used at all, may vary within wide limits. They are used in amounts of preferably 0 to 5 % by weight, more preferably 0 to 2 % by weight, even more preferably 0 to 1 % by weight, based on the total amount of monomeric compounds that have NCO groups. It is however most preferred that their amount is 0, i.e. that only components Al) and A2) are used. In other words, the combined amount of components Al) and A2) is preferably at least 95 % by weight, more preferably 95 - 100 % by weight or 98 - 100 % by weight, even more preferred 99 - 100 % by weight, most preferred 100 % by weight, in each case based on the total weight of the isocyanate composition.

[0037] It is irrelevant by which processes the above mentioned diisocyanates are generated, i.e. with or without use of phosgene. Preferred in the industrial production of the isocyanates is the phosgenation in the liquid-phase or the gas-phase and even more preferred by gas-phase phosgenation as described for example in EP 0 764 633 A2. ISODI, IDDI and IMANDI are preferably prepared from the respective diamines.

[0038] As catalysts A3) to be optionally used for the NCO-NCO reactions to form the isocyanurate structures the typical compounds known to be catalytically active to isocyanates are suitable. These catalysts include, in addition to compounds of ionic structure for example with "onium" cations (ammonium, phosphonium, etc.) and nucleophilic anions such as hydroxide, alkanoate, carboxylate, heterocycles having at least one negatively charged nitrogen atom in the ring, especially azolate, imidazolate, triazolate, tetrazolate, fluoride, hydrogendifluoride, higher polyfluorides or mixtures of these (adducts of more than one equivalent of HF onto compounds containing fluoride ions), also neutral bases such as tertiary amines or phosphanes (phosphines).

[0039] The progress of the reaction in the process of the invention can be monitored by determining the NCO content by titrimetric means as per DIN EN ISO 11909:2007-05. On attainment of the desired NCO content (“degree of polymerization”) the reaction is stopped by suitable means depending on the modification reaction and / or the use of a catalyst or not. Preferably catalysts are deactivated by addition of suitable catalyst poisons. 2024PF30135-Foreign Countries

[0040] 5

[0041] According to a further preferred embodiment, the reaction is taken to a point where the reaction mixture has a degree of oligomerization of 5 % to 40%, preferably of 10% to 30%.

[0042] " Degree of oligomerization" presently refers to the percentage of the isocyanate groups originally present in the starting mixture that is consumed during the reaction according to the invention. The degree of oligomerization in percent can be calculated according to the following formula:

[0043] Degree of oligomerization = (NCO start - NCO end) / NCO start x 100.

[0044] The reaction can be discontinued, for example, when the target degree of oligomerization has been reached. This degree of oligomerization is reached generally after a reaction time of 30 minutes to 8 hours, preferably of 1 to 6 hours.

[0045] The reaction may be terminated for example by cooling the reaction mixture to room temperature. In general, however, the reaction is ended by addition of a catalyst poison and optional subsequent brief heating of the reaction mixture to a temperature above 80°C, for example. It is also possible to use a combination of both options to terminate the reaction, i.e. by cooling the mixture to room temperature and adding a catalyst poison, wherein the catalyst poison can be added before, during or after the reaction mixture is cooled down.

[0046] Examples of suitable catalyst poisons are inorganic acids such as hydrochloric acid, phosphorous acid or phosphoric acid, acyl chlorides such as acetyl chloride, benzoyl chloride or isophthaloyl dichloride, sulfonic acids and sulfonic esters, such as methanesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, perfluorobutane sulfonic acid, dodecylbenzenesulfonic acid, methyl and ethyl p-toluenesulfonates, monoalkyl and dialkyl phosphates such as monotridecyl phosphate, dibutyl phosphate, and dioctyl phosphate, and also silylated acids, such as trimethylsilyl methanesulfonate, trimethylsilyl trifluoromethane sulfonate, tris(trimethylsilyl) phosphate, and diethyl trimethylsilyl phosphate.

[0047] The amount of catalyst poison needed to end the reaction is dependent here on the amount of catalyst used; in general, an equivalent amount of the catalyst poison is used, based on the catalyst used at the start. Taking account, though, losses of catalyst possibly occurring during the reaction, 20 to 80 equivalent% of the catalyst poison, based on the amount of catalyst originally used, may also be sufficient to end the reaction.

[0048] The reaction of the isocyanate composition may be conducted with or without solvent. Suitable solvents are, for example, the customary paint solvents that are known per se such as ethyl acetate, butyl acetate, ethylene glycol monomethyl or monoethyl ether acetate, 1 -methoxyprop-2 -yl acetate, 3-methoxy-n-butyl acetate, acetone, 2-butanone, 4-methyl-2-pentanone, cyclohexanone, toluene, xylene, chlorobenzene, white spirit, more highly substituted aromatics, of the kind available commercially, for 2024PF30135-Foreign Countries

[0049] 6

[0050] example, under the names Solventnaphtha, Solvesso®, Isopar®, Nappar®, Varsol® (ExxonMobil Chemical Central Europe, Cologne, Germany) and Shellsol® (Shell Deutschland Oil GmbH, Hamburg, Germany), and also solvents such as propylene glycol diacetate, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol ethyl and butyl ether acetate, N-methylpyrrolidone and N-methylcaprolactam, or any desired mixtures of such solvents. These solvents are so-called inert solvents, i.e. they do not react with the reactive groups of the starting components.

[0051] Besides these inert solvents, solvents, which react with the reactive groups of the starting components and are incorporated into the product, i.e. the resulting polyisocyanates, can also be used. Examples of such solvents are: methanol, ethanol, n-propanol, isopropanol, n-butanol, n-hexanol, 2 -ethyl- 1 -hexanol, ethylene glycol, propylene glycol, the isomeric butanediols, 2 -ethyl- 1,3 -hexanediol or glycerin, ether alcohols, such as l-methoxy-2 -propanol, 3-ethyl-3-hydroxymethyloxetane, tetrahydrofurfuryl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol and dipropylene glycol, ester alcohols, such as ethylene glycol monoacetate, propylene glycol monolaurate, glycerol mono- and diacetate, glycerol monobutyrate or 2,2,4-trimethyl-1,3 -pentanediol monoisobutyrate, unsaturated alcohols such as allyl alcohol, 1,1 -dimethylallyl alcohol or olein alcohol, and araliphatic alcohols such as benzyl alcohol, and higher molecular weight polyethylene glycols, propylene glycols, mixed polyethylene / polypropylene glycols and their monoalkyl ethers.

[0052] The reaction mixture obtained after the reaction of the isocyanate composition is referred to herein as “raw polyisocyanate composition”.

[0053] Distillation step

[0054] The obtained raw polyisocyanate composition is subjected to distillation in order to at least partially remove unreacted moieties of components Al) and A2). The expression "at least partially" refers to the fact that the content of unreacted monomeric diisocyanates is / cannot be 100% removed by distillation, so that small moieties remain in the end product, i.e. the polyisocyanate composition comprising at least one isocyanurate structure (see the following statements on the residual monomeric diisocyanate content under the heading " Polyisocyanate composition comprising at least one isocyanurate structure "). In addition to unreacted moieties of components Al) and A2) other volatile constitutents, if present, such as unreacted moieties of further monomeric diisocyanates different from components Al) and A2) or solvents, can be at least partially removed by the distillation step.

[0055] The distillation is preferably carried out as thin film distillation, short path distillation and / or falling film distillation, preferably in a vacuum, in one or several evaporator stages, with the one or the final evaporator stage of the several stages preferably having a pressure of less than 1.0 mbar, preferably less 2024PF30135-Foreign Countries

[0056] 7

[0057] than 0.25 mbar, particularly preferably less than 0.2 mbar. On a production scale, the distillation is preferably carried out in several stages, with pressures of less than 30 mbar in the first stages, preferably less than 20 mbar, particularly preferably less than 10 mbar and a pressure of less than 1 mbar, preferably less than 0.25 mbar, particularly preferably less than 0.2 mbar in the last evaporator stage.

[0058] In an embodiment of the invention a catalyst poison is added to the raw polyisocyanate composition before or during the distillation is performed.

[0059] The distillation is preferably carried out at a temperature of 100 to 200°C, more preferably of 120 to 200°C.

[0060] It is possible to use different or multiple distillation methods such as thin film distillation, falling film distillation or short path distillation.

[0061] The design of the evaporator stages, evaporation units and distillation apparatus for the possible distillation methods can be chosen arbitrarily. It can be advantageous to heat these with direct steam and / or a pressurized water circuit. In addition, the evaporation units preferably contain several condensers and vacuum pumps. In a preferred embodiment, the distillation setup comprises or consists of three evaporator stages and particularly preferably comprises or consists of a falling film evaporator as the first evaporation stage, a thin film evaporator or falling film evaporator as the second evaporator stage and a short-path evaporator as the third evaporator stage. The above described process leads to polyisocyanate compositions with a low residual monomeric diisocyanate content.

[0062] According to the invention, component A) is characterized in that it has a residual monomeric diisocyanate content of diisocyanates of components Al) and A2) of less than 1 % by weight, preferably less than 0.5 % by weight, and more preferably less than 0.1 % by weight, based on the total weight of component A), in each case determined by gas chromatography in accordance with DIN EN ISO 10283:2007-11 with internal standard.

[0063] In case further monomeric diisocyanates different from components Al) and A2) are used in the synthesis of the raw polyisocyanate composition the residual monomeric diisocyanate content of all these diisocyanates, i.e. of diisocyanates of components Al) and A2) and of the additional monomeric diisocyanates, is preferably less than 1 % by weight, preferably less than 0.5 % by weight and more preferably less than 0.1 % by weight, based on the total weight of component A).

[0064] The residual monomeric diisocyanate content is determined by gas chromatography in accordance with DIN EN ISO 10283:2007-11 with internal standard.

[0065] In a preferred embodiment, component A) is characterized in that it has an NCO content determined in accordance with DIN EN ISO 11909:2007-05 of from 5.8 to 25.9% by weight, preferably from 7.8 to 2024PF30135-Foreign Countries

[0066] 8

[0067] 24.9% by weight, particularly preferably from 9.7 to 23.9% by weight, based on the total weight of component A).

[0068] In addition to isocyanurate structures the polyisocyanate composition A) may also contain allophanate, iminooxadiazinedione, urethane, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and / or biuret structures.

[0069] In a preferred embodiment the polyisocyanate composition A) contains at least one allophanate structure, iminooxadiazinedione structure, urethane structure, urea structure, uretdione structure, oxadiazinetrione structure, carbodiimide structure, thiourethane structure, thioallophanate structure and / or biuret structure in addition to the at least one isocyanurate structure.

[0070] In a preferred embodiment the polyisocyanate composition A) comprises, based on the total solid content of the polyisocyanate composition A), > 99 % by weight, preferably > 99.5 % by weight and more preferably > 99.9 % by weight of polyisocyanates containing at least one isocyanurate structure and at least one allophanate structure, iminooxadiazinedione structure, urethane structure, urea structure, uretdione structure, oxadiazinetrione structure, carbodiimide structure, thiourethane structure, thioallophanate structure and / or biuret.

[0071] In a preferred embodiment of the above preferred embodiments the fraction of isocyanurate structures in the polyisocyanate composition A) is > 70 to < 99 mol%, preferably > 75 to < 99 mol% and more preferably > 80 to < 99 mol%, in each case based on the total amount of isocyanurate, allophanate, iminooxadiazinedione, urethane, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and biuret structures of the polyisocyanate composition A).

[0072] The total fraction of urethane and / or allophanate structures is at most 30 mol% (> 0 to < 30 mol%), preferably at most 20 mol% (> 0 to < 20 mol%), in each case based on the total amount of isocyanurate, allophanate, iminooxadiazinedione, urethane, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and biuret structures in the polyisocyanate composition A).

[0073] The total fraction of iminooxadiazinedione, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and / or biuret structures is at most 10 mol% (> 0 to < 10 mol%), preferably at most 5 mol% (> 0 to < 5 mol%), in each case based on the total amount of isocyanurate, allophanate, iminooxadiazinedione, urethane, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and biuret structures in the polyisocyanate composition A).

[0074] The fractions (mol%) of isocyanurate, iminooxadiazinedione, allophanate, urethane, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and biuret structures are determined by13C NMR spectroscopy. The measurements are conducted on the Bruker DPX 400 or DRX 700 instruments on approx. 50% (13C NMR) samples in dry C6D6, at 100 or 176 MHz (13C NMR). The C6D5H 2024PF30135-Foreign Countries

[0075] 9

[0076] present in the NMR solvent is used as reference signal (7.15 ppm, ¹H-NMR). or the solvent signal itself (average signal of the 1:1:1 triplet at 128.0 ppm in the13C NMR).

[0077] The weight ratio of (3R,3aR,6S,6aR)-3,6-diyl-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-, (3S,3aR,6S,6aR)-3,6-diyl-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan- and / or (3R,3aR,6R,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-structures in polyisocyanate composition A) to structures -R- in polyisocyanate composition A), wherein R corresponds to the organic residue R in the general formula OCN-R-NCO of component A2), is > 2.5: 1 to < 8: 1, preferably > 3: 1 to < 7.6: 1, most preferably > 3.2: 1 to < 7.4: 1, wherein the fraction of these structures in the polyisocyanate composition is determined using NMR spectroscopic analysis using the same equipment and conditions as described above.

[0078] The polyisocyanate compositions A) are storage stable at 24°C for at least 14 days, preferably at least 21 days, more preferably at least 28 days. Storage stable means that they show no sign of solids formation.

[0079] Component B: NCO-reactive compounds

[0080] NCO-reactive compounds of component B) may be all compounds known to those skilled in the art -including in any desired mixtures with one another - that have an average OH, NH or SH functionality of at least 1.5. These may, for example, be low molecular weight diols (e.g. ethane- 1,2-diol, propane-1,3- or -1,2-diol, butane- 1,4-diol), triols (e.g. glycerol, trimethylolpropane) and tetraols (e.g. pentaerythritol), short-chain polyamines, but also polyaspartic esters, polythiols and / or polyhydroxy compounds such as polyether polyols, polyester polyols, polyurethane polyols, polysiloxane polyols, polycarbonate polyols, polyether polyamines, polybutadiene polyols, polyacrylate polyols and / or polymethacrylate polyols, and the copolymers thereof, called polyacrylate polyols hereinafter.

[0081] According to a preferred embodiment, the NCO-reactive compound is a polyhydroxy compound, preferably a polyether polyol, polyester polyol, polycarbonate polyol or polyacrylate polyol.

[0082] Polyester polyols suitable as hydroxy-functional compounds include for example those having an average molecular weight calculable from functionality and hydroxyl number of 200 g / mol to 4000 g / mol, preferably of 250 g / mol to 2500 g / mol, having ahydroxyl group content of l%to 21% by weight, preferably 2% to 18% by weight, such as are producible in a manner known per se by reacting polyhydric alcohols, for example those mentioned above having 2 to 14 carbon atoms, with deficit amounts of polybasic carboxylic acids, corresponding carboxylic anhydrides, corresponding polycarboxylic esters of lower alcohols, or lactones.

[0083] The acids or acid derivatives used for producing the polyester polyols may be aliphatic, cycloaliphatic and / or aromatic in nature and may optionally be substituted, for example by halogen atoms, and / or 2024PF30135-Foreign Countries

[0084] 10

[0085] unsaturated. Examples of suitable acids include for example polybasic carboxylic acids in the molecular weight range 118 to 300 g / mol or derivatives thereof such as for example succinic acid, adipic acid, sebacic acid, phthalic acid, isophthalic acid, trimellitic acid, phthalic anhydride, tetrahydrophthalic acid, maleic acid, maleic anhydride, dimeric and trimeric fatty acids, dimethyl terephthalate and bisglycol terephthalate.

[0086] Production of the polyester polyols may also employ any desired mixtures of these starting compounds recited by way of example.

[0087] A type of polyester polyols alternatively employable as the hydroxy-functional compound is selected from those producible by ring opening in a manner known per se from lactones and simple polyhydric alcohols, for example those mentioned by way of example hereinabove, as starter molecules. Examples of suitable lactones for producing these polyester polyols are for example β-propiolactone, γ-butyrolactone, δ- and δ-valerolactone, ε-caprolactone. 3,5,5- and 3,3,5-trimethylcaprolactone or any desired mixtures of such lactones.

[0088] Polyhydroxyl compounds of the polycarbonate type which are suitable as hydroxy-functional compounds especially include the polycarbonate diols known per se such as are obtainable for example by reaction of dihydric alcohols, for example those recited by way of example in the above list of polyhydric alcohols in the molecular weight range 62 to 400 g / mol, with diaryl carbonates, such as for example diphenyl carbonate, dialkyl carbonates, such as for example dimethyl carbonate, or phosgene. Suitable polyhydroxyl compounds of the polyester carbonate type which are suitable as hydroxyfunctional compounds include in particular the ester- and carbonate-comprising diols that are known per se, such as are obtainable for example according to the teaching of DE-A 1 770245 or WO 03 / 002630 by reacting dihydric alcohols with lactones of the type recited by way of example above, in particular ε-caprolactone and subsequent reaction of the resulting polyester diols with diphenyl carbonate or dimethyl carbonate.

[0089] Polyether polyols suitable as hydroxy-functional compounds include in particular those having an average molecular weight, calculable from functionality and hydroxyl number, of 200 to 2000 g / mol, preferably 250 to 1000 g / mol, having a hydroxyl group content of 1.6% to 25% by weight, preferably 3.6% to 20% by weight, such as are obtainable in a manner known per se by alkoxylation of suitable starter molecules. To produce these polyether polyols any desired polyhydric alcohols, such as the above-described simple polyhydric alcohols having 2 to 14 carbon atoms, may be employed as starter molecules. Suitable alkylene oxides for the alkoxylation reaction especially include ethylene oxide and propylene oxide which may be employed in the alkoxylation reaction in any sequence or else in admixture. 2024PF30135-Foreign Countries

[0090] 11

[0091] Suitable polyether polyols also include the polyoxytetramethylene glycols known per se, such as are obtainable for example by polymerization of tetrahydrofuran according to H. Meerwein et al., Angew. Chem. 72, 1960, 927 - 934.

[0092] Suitable polyacrylate polyols are generally copolymers and preferably have mass-average molecular weights Mw of between 1000 and 20 000 g / mol, especially between 5000 and 10 000 g / mol, measured in each case by means of gel permeation chromatography (GPC) according to DIN 55672-1:2016-03 in tetrahydrofuran at 25°C against a polystyrene standard. The glass transition temperature of the copolymers is preferably between -100°C and 100°C, especially between -50°C and 80°C (measured by means of DSC measurements according to DIN EN ISO 11357-2:2014). Suitable polyacrylate polyols preferably have an OH number of 60 to 250 mg KOH / g, especially between 70 and 200 mg KOH / g, and an acid number of between 0 and 30 mg KOH / g. The acid number here indicates the number of mg of potassium hydroxide which is used for neutralization of 1 g of the respective compound (DIN EN ISO 2114:2000).

[0093] The production of suitable polyacrylate polyols is known to those skilled in the art. They are obtained by radical polymerization of olefmically unsaturated monomers having hydroxyl groups or by radical copolymerization of olefmically unsaturated monomers having hydroxyl groups with optionally other olefmically unsaturated monomers, for example ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, butyl acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, amyl acrylate, amyl methacrylate, hexyl acrylate, hexyl methacrylate, ethylhexyl acrylate, ethylhexyl methacrylate, 3,3,5-trimethylhexyl acrylate, 3,3,5-trimethylhexyl methacrylate, stearyl acrylate, stearyl methacrylate, lauryl acrylate or lauryl methacrylate, cycloalkyl acrylates and / or cycloalkyl methacrylates, such as cyclopentyl acrylate, cyclopentyl methacrylate, isobomyl acrylate, isobomyl methacrylate or especially cyclohexyl acrylate and / or cyclohexyl methacrylate. Suitable olefmically unsaturated monomers having hydroxyl groups are especially 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3 -hydroxypropyl acrylate, 3 -hydroxypropyl methacrylate, 3-hydroxybutyl acrylate, 3 -hydroxybutyl methacrylate and especially 4-hydroxybutyl acrylate and / or 4-hydroxybutyl methacrylate.

[0094] Further monomer units used for the polyacrylate polyols may be vinylaromatic hydrocarbons, such as vinyltoluene, alpha-methylstyrene or especially styrene, amides or nitriles of acrylic acid or methacrylic acid, vinyl esters or vinyl ethers, and in minor amounts especially acrylic acid and / or methacrylic acid. The inventive compositions optionally contain catalysts for controlling the curing rate (component C), for example the catalysts customary in isocyanate chemistry, such as tert, amines such as triethylamine, pyridine, methylpyridine, benzyldimethylamine, N, N-endoethylenepiperazine, N-methylpiperidine, pentamethyldiethylenetriamine, N, N-dimethylaminocyclohexane, N, N'-dimethylpiperazine or metal 2024PF30135-Foreign Countries

[0095] 12

[0096] salts such as iron(III) chloride, zinc chloride, zinc 2-ethyl caproate, tin(II) octanoate, tin(II) ethyl caproate, dibutyltin(IV) dilaurate, bismuth(III )-2 -ethylhexanoate, bismuth(III) octoate or molybdenum glycolate.

[0097] As can be seen from the examples the inventive compositions show fast chemical and physical drying, even without using a catalyst which catalyzes the reaction of components A) and B). In a preferred embodiment of the invention the inventive composition does not comprise any catalyst C).

[0098] Catalysts A3) which fall under the definition of component C) but are deactivated by a catalyst poison do not belong to catalysts C).

[0099] The inventive compositions optionally contain auxiliaries and additives (component D), which may for example be co-binders, desiccants, fillers, cosolvents, color or effect pigments, thickeners, matting agents, light stabilizers, coatings additives such as dispersants, thickeners, defoamers and other auxiliaries such as adhesives, fungicides, bactericides, stabilizers or inhibitors and catalysts or emulsifiers which are known to those skilled in the art.

[0100] According to the invention, components A) and B) are used in amounts corresponding to an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 2:1 to 0.5 to 1, preferably 1.5:1 to 0.8:1, more preferably 1.1:1 to 0.9:1.

[0101] The invention also relates to the use of a polyisocyanate composition comprising at least one isocyanurate structure according to component A) as described above, as well as the use of the inventive compositions as described in the synthesis of coating compositions, adhesives or sealants.

[0102] The invention further relates to coating compositions, adhesives or sealants obtainable by the use of polyisocyanate compositions comprising at least one isocyanurate structure according to component A) as described above, as well as by the use of the inventive composition.

[0103] The coating composition, adhesive or sealant may be a one-component or a two-component system. For use in a one-component system the free isocyanate groups of component A) are at least partially deactivated (“blocked”) with one or more blocking agents. “At least partially“ means that at least (3= ) 70 mol%, preferably at least (2= ) 85 mol%, particularly preferably at least (2=) 95 mol% of the isocyanate groups are blocked with blocking agents. The at least partially deactivated isocyanate groups or the at least partially blocked polyisocyanate composition A) can be produced, for example, by allowing the polyisocyanate composition A) to react with the blocker agent. Examples of blocking agents include blocking agents of oxime, phenol, alcohol, imine, amine, carbamic acid, urea, imidazole, imide, mercaptan, active methylene, acid amide (lactam) and bisulfites. 2024PF30135-Foreign Countries

[0104] 13

[0105] Each of the inventive two-component and one-component system can be used as solvent-borne or waterborne system. In this regard, typical solvents, such as those mentioned above with regard to the synthesis of component A) or water can be used.

[0106] The invention further relates to a substrate comprising a coating composition, an adhesive or a sealant obtainable as described above, wherein the coating composition, adhesive or sealant is uncured, partially cured or fully cured.

[0107] The invention further relates to a method for coating a substrate comprising the steps:

[0108] i) providing an optionally pretreated substrate,

[0109] ii) applying the inventive coating composition to the substrate, and

[0110] iii) partially or fully curing of the coating composition.

[0111] For use in step i) of the aforementioned processes according to the invention the substrates may be uncoated or coated. Examples of primers include solvent-based or aqueous primers, primer-surfacers or filler-surfacers as well as basecoats.

[0112] Suitable substrates are, for example, substrates comprising one or more materials, especially including so-called composite materials. A substrate formed from at least two materials is referred to in accordance with the invention as composite material. Suitable materials include glass, metal, paper, wood, plastics, stone and concrete.

[0113] Suitable methods of application are, for example, printing, painting, rolling, casting, dipping, fluidized bed methods and / or spraying, for example compressed air spraying, airless spraying, high rotation, electrostatic spray application (ESTA), optionally combined with hot spray application, for example hot-air spraying.

[0114] The curing in step iii) is conducted at a temperature range of > 0°C to < 160 °C, preferably > 20°C to < 80°C.

[0115] Unless stated otherwise, all number-average molecular weights given in this document are determined by GPC according to DIN EN ISO 13885-1:2021-11 using polystyrene as standard and tetrahydrofuran as eluent.

[0116] The comparative examples and examples which follow are intended to further illustrate the invention but without limiting it. 2024PF30135-Foreign Countries

[0117] 14

[0118] Examples:

[0119] All percentages, unless noted otherwise, are to be understood to mean percent by weight.

[0120] All reactions were conducted under a nitrogen atmosphere in glass apparatuses dried beforehand under reduced pressure at 150-200 °C.

[0121] Mol% data or the simple existence of the isocyanurate, iminooxadiazinedione, allophanate, urethane, urea, uretdione, oxadiazinetrione, carbodiimide, thiourethane, thioallophanate and / or biuret structure present in the polyisocyanates were determined by13C NMR spectroscopy and always relate, unless noted otherwise, to the sum total of the NCO conversion products. The measurements were conducted on the Bruker DPX 400 or DRX 700 instruments on approx. 50% (13C NMR) samples in dry C6D6, unless noted otherwise, at 100 or 176 MHz (13C NMR). The C6D5H present in the NMR solvent was used as reference signal (7.15 ppm, ’H-NMR), or the solvent signal itself (average signal of the 1:1:1 triplet at 128.0 ppm in the13C NMR.

[0122] Dynamic viscosities were determined at 23 °C using the MCR 501 rheometer (from Anton Paar) in accordance with DIN EN ISO 3219:1994-10. Measurement at different shear rates ensured that Newtonian flow behavior can be assumed. Details regarding the shear rate can therefore be omitted. The NCO content was determined by titration in accordance with DIN EN ISO 10283:2007-11.

[0123] The residual monomer content was determined by gas chromatography in accordance with DIN EN ISO 10283:2007-11 with internal standard.

[0124] Starting materials used

[0125] HDI Covestro Deutschland AG

[0126] IPDI Covestro Deutschland AG

[0127] PDI Covestro Deutschland AG

[0128] Setalux D A 870 BA The acrylic polyol was obtained from Allnex GmbH (Deutschland). It has an OH number of 4.2 % (calculated on non-volatiles) and is supplied in butyl acetate. It has an equivalent weight of 575 g / eq.

[0129] Byk 141 Silicone defoamer from Byk Additives and Instruments GmbH, Deutschland Byk 331 Silicone defoamer from Byk Additives and Instruments GmbH, Deutschland Byk 349 Silicone defoamer from Byk Additives and Instruments GmbH, Deutschland Addocat 201 Dibutyltin dilaurate from Lanxess Deutschland GmbH 2024PF30135-Foreign Countries

[0130] 15

[0131] Tinuvin 292 Hindered amine light stabilizer, BASF SE, Deutschland

[0132] Tinuvin 1130 Hydroxyphenyl benzotriazole liquid UV absorber, BASF SE, Deutschland MPA 1 -methoxypropyl -2 -acetate, anhydrous, was obtained from Azelis, St. Augustin Xylene Obtained from Azelis, St. Augustin

[0133] Butyl acetate Obtained from Azelis, St. Augustin

[0134] Characterization of application coating films

[0135] Drying time Tl, T3 and T4 were carried out according to DIN EN ISO 9117-5:2010-07.

[0136] The pendulum damping (“hardness") according to König was determined to DIN EN ISO 1522:2007-04 on glass plates.

[0137] Solvent resistance was tested according to DIN EN ISO 4628-1:2016-07 small amounts of each of the solvents xylene, 1 -methoxypropyl -2 -acetate, ethyl acetate and acetone were placed in test tubes and provided with a cottonwool pad at the opening, thus forming a solvent-saturated atmosphere within the test tubes. The test tubes were subsequently brought with the cotton pad onto the surface of the coating, where they remained for 5 minutes. After the solvent had been wiped off, the film was examined for destruction / softening / loss of adhesion and rated (0=no change, 5=film completely dissolved). The evaluations reported are those for the four solvents in the order in each case of xylene (X), 1-methoxypropyl-2 -acetate (MPA), ethyl acetate (EA) and acetone (A) in the form of four successive digits.

[0138] To test the coatings towards resistance towards acid and base a cotton pad was immersed in 10% H2SO4or 10% NaOH and then placed on top of a coating which was then covered with a small glass vial. The solution remained on the coatings for 24 h. After this time, fresh water was used to remove the acid or base solution from the coatings. The panel was then dried with paper and then the panels were examined and rated (0=no change, 5=film completely dissolved).

[0139] Viscosity increase was used to classify chemical reactivity of the formulations and was measured with a DIN cup (4 mm diameter) according to DIN EN ISO 2431.

[0140] Polyisocyanates

[0141] Polyisocyanate 1: IDDI polyisocyanate (not inventive):

[0142] In a 500 mL three-neck flask with septum, internal thermometer and reflux condenser, IDDI (139.11 g) was charged, and the mixture was tempered to 60°C. The NCO value of this mixture was 42.8%. Subsequently, catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride, 24% in 2-ethylhexanol, 25 ppm on active substance) was added dropwise. The mixture was quenched with dodecylbenzenesulfonic 2024PF30135-Foreign Countries

[0143] 16

[0144] acid (40% in iPrOH) upon reaching an NCO value of 40.7%. An attempt was then made to purify the resin by thin fdm distillation (190°C / 0.19 mbar). However, it was found that IDDI polyisocyanate resins are not suitable for purification by thin film distillation, as their melt viscosity is too high. By perforating with isooctane, a large portion of the IDDI could be removed from the resin. The resulting resin was not flowable and was dissolved 70% in boiling butyl acetate. After cooling to room temperature, the resin precipitated again as a colorless solid after 24h.

[0145] Viscosity (70% in butyl acetate): initially 3500 mPas, after 24h: solid precipitate

[0146] NCO content: 14.9%

[0147] Polyisocyanate 2: ISODI polyisocyanate (not inventive):

[0148] In a 500 mL three-neck flask with septum, internal thermometer and reflux condenser, ISODI (139.11 g) was charged, and the mixture was tempered to 60°C. The NCO value of this mixture was 42.8%. Subsequently, catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride, 24% in 2-ethylhexanol, 25 ppm on active substance) was added dropwise. The mixture was quenched with dodecylbenzene sulfonic acid (40% in iPrOH) upon reaching an NCO value of 40.7%. An attempt was then made to purify the resin by thin film distillation (190°C / 0.19 mbar). However, it was observed that ISODI polyisocyanate resins are not suitable for purification by thin film distillation, as their melt viscosity is too high. ISODI polyisocyanates could not be isolated.

[0149] Polyisocyanate 3: Mixed Trimer IDDI-HDI (inventive)

[0150] Experiment 1: In a 500 mL three-neck flask with septum, internal thermometer and reflux condenser, IDDI (150.50 g) and HDI (150.50 g) were charged, and the mixture was tempered to 60°C. The NCO value of this mixture was 46%. Subsequently, catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride, 24% in 2-ethylhexanol, 10 ppm based on active component) was added dropwise. The mixture was quenched with dodecylbenzenesulfonic acid (40% in iPrOH) upon reaching an NCO value of 43.7% and subsequently purified by thin film distillation (190°C / 0.19 mbar). A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of IDDI structures to HDI structures is approximately 7.3.

[0151] Experiment 2: In a 500 mL three-neck flask with septum, internal thermometer and reflux condenser, IDDI (108.70 g) and HDI (191.70 g) were charged, and the mixture was tempered to 60°C. The NCO value of this mixture was 46.6%. Subsequently, catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride, in 24% 2-ethylhexanol, 17 ppm based on active component) was added dropwise, causing the reaction mixture to heat up to 88°C. The mixture was quenched with dodecylbenzene sulfonic acid 2024PF30135-Foreign Countries

[0152] 17

[0153] (40% in iPrOH) upon reaching an NCO value of 40.8% and subsequently purified by thin film distillation (190°C / 0.19 mbar). A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of IDDI structures to HDI structures is approximately 3.3. The resins from experiments 1 and 2 were combined and diluted to 60% solids content.

[0154] Polyisocyanate 3 with the following characteristics was obtained: Resin structure (13C-NMR) from IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of IDDIstructures to HDI structures is approximately 4.3. After storage of the resin for 4 weeks at 24°C, no sign of solid formation could be observed.

[0155] Isocyanurate structures: 98 mol%

[0156] Allophanate / Urethan structures: 2 mol%

[0157] Monomeric Diisocyanates: 0.1%

[0158] NCO content (resin): 20.5%

[0159] Solid Content: 60% in BA

[0160] Viscosity (23°C, 60% BA): 252 mPas

[0161] Polyisocyanate 4: Mixed Trimer ISODI-IDDI-HDI (inventive)

[0162] Experiment 1: In a 500 mL three-neck flask with septum, internal thermometer and reflux condenser, ISODI (147.60 g), IDDI (147.60 g) and HDI (147.60 g) were charged, and the mixture was tempered to 60°C. The NCO value of this mixture was 44%. Subsequently, catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride in 2-ethylhexanol, 35 ppm based on active component) was added dropwise. The mixture was quenched with dodecylbenzenesulfonic acid (40% in iPrOH) upon reaching an NCO value of 40.5% and subsequently purified by thin film distillation (190°C / 0.12 mbar). A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from ISODI / IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of IDDI and ISODI structures (sum of both) to HDI structures is approximately 6.1. The distillate consisted of approx. 29% IDDI, 31% ISODI and 40% HDI.

[0163] Experiment 2: The distillate from experiment 1 was trimerized and processed in an analogous manner. A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from ISODI / IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of IDDI and ISODI structures (sum of both) to HDI structures is approximately 6.1. Viscosity (70% in butyl acetate): 2024PF30135-Foreign Countries

[0164] 18

[0165] 7000 mPas NCO content: 14.2% The distillate consisted of approx. 24% IDDI, 30% ISODI and 46% HDI.

[0166] Experiment 3: The distillate from experiment 2 was trimerized and processed in an analogous manner. A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from ISODI / IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of IDDI and ISODI structures (sum of both) to HDI structures is approximately 4.6. The distillate consisted of approx.

[0167] 20% IDDI, 28% ISODI and 52% HDI.

[0168] The resins from experiments 1 to 3 were combined and diluted to 60% solids content.

[0169] Polyisocyanate 4 with the following characteristics was obtained: Resin structure (13C-NMR) from ISODI / IDDI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of incorporated IDDI and ISODI structures (sum of both) to HDI structures is approximately 4.9. After storage of the resin for 4 weeks at 24°C, no sign of solid formation could be observed.

[0170] Isocyanurate structures: 98 mol%

[0171] Allophanate / Urethan structures: 2 mol%

[0172] Monomeric Diisocyanates: <0.1%

[0173] NCO content (solid resin): 20.0%

[0174] Solid content: 60% in BA

[0175] Viscositiy (23°C, 60% BA): 450 mPas

[0176] Polyisocyanate 5: Mixed Trimer ISODI-HDI (inventive)

[0177] In a 2000 mL three-neck flask with septum, internal thermometer and reflux condenser, ISODI (350.00 g, 1.00 eq) and HDI (1000.00 g) were charged and the mixture was tempered to 60°C. The NCO value of this mixture was 48.0%. Subsequently, an alcohol mixture containing 11,8 g of 2-Ethylhexanol (0.05 eq) and 11,8 g of 2-Ethylhexan-l,3-diole (0.05 eq) was added and stirred till a NCO value of 47.05% was reached. After that, catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride, 24% in 2-ethylhexanol, 35 ppm on active content) was added dropwise. The mixture was quenched with dodecylbenzene sulfonic acid (40% in iPrOH) upon reaching an NCO value of 39.4% and subsequently purified by thin film distillation (140°C / 0.001 mbar). A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from ISODI / HDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of incorporated ISODI to HDI structures is approximately 2.8. After storage of the resin for 4 weeks at 24°C, no sign of solid formation could be observed. Isocyanurate structures: 85 mol% 2024PF30135-Foreign Countries

[0178] 19

[0179] Allophanate / Urethan structures: 15 mol%

[0180] Monomeric Diisocyanates: <0.1%

[0181] NCO content (solid resin): 19.1%

[0182] Solid content: 70% in BA

[0183] Viscositiy (23°C, 70% in BA): 724 mPas

[0184] Polyisocyanate 6: Mixed Trimer ISODI-PDI (inventive)

[0185] In a 2000 mL three-neck flask with septum, internal thermometer and reflux condenser, ISODI (354.00 g, 1.0 eq) and PDI (1000.00 g) were charged and the mixture was tempered to 60°C. The NCO value of this mixture was 51.4%. Subsequently, a alcohol mixture containing 14,3 g of 2-Ethylhexanol (0.05 eq) and 14,3 g of 2-Ethylhexan-l,3-diole (0.05 eq) was added and stirred till a NCO value of 47.05% was reached. After that catalyst (5-azaspiro[4.5]decan-5-ium fluoride hydrofluoride, 24% in 2-ethylhexanol, 35 ppm on active content) was added dropwise. The mixture was quenched with dodecylbenzene sulfonic acid (40% in iPrOH) upon reaching an NCO value of 42.4% and subsequently purified by thin film distillation (140°C / 0.001 mbar). A flowable resin with the following characteristics was obtained: Resin structure (13C-NMR) from ISODI / PDI mixed polyisocyanates, predominantly polyisocyanurates, weight ratio of incorporated ISODI to PDI structures is approximately 4.8. After storage of the resin for 4 weeks at 24°C, no sign of solid formation could be observed.

[0186] Isocyanurate structures: 83 mol%

[0187] Allophanate / Urethan structures: 17 mol%

[0188] Monomeric Diisocyanates: <0.1%

[0189] NCO content (solid resin): 20.0%

[0190] Solid content: 70% in BA

[0191] Viscositiy (23°C, 70% BA): 544 mPas

[0192] Polyisocyanate 7:

[0193] An isocyanurate structures containing hexamethylene diisocyanate (HD I) polyisocyanate was prepared by catalytic trimerization of HDI in accordance with Example 11 of EP -A 330966, with the modification that the reaction was stopped at an NCO content of the crude mixture of 40% by addition of dibutyl phosphate. Unreacted HDI was then separated off by thin-film distillation at a temperature of 130° C and a pressure of 0.2 mbar. The product had the following characteristics and composition:

[0194] NCO content: 21.7% 2024PF30135-Foreign Countries

[0195] 20

[0196] Monomeric HDI: 0.1%

[0197] Viscosity (23 °C) 3080 mPas

[0198] Solid content: 100%

[0199] Polyisocyanate 8:

[0200] An isocyanurate structures containing pentamethylene diisocyanate (PDI) polyisocyanate was prepared by catalytic trimerization of PDI by the process described in WO 2016 / 146579 for polyisocyanate component A2). The reaction was deactivated at an NCO content of the crude mixture of 36.7% by adding an equimolar amount of dibutyl phosphate, based on the amount of catalyst used, and stirring at 80 °C for 30 minutes. Unreacted PDI was then separated off by thin-fdm distillation at a temperature of 140 °C and a pressure of 0.5 mbar. The product had the following characteristics and composition: NCO content: 21.8%

[0201] monomeric PDI: 0.09%

[0202] Viscosity (23 °C): 9850 mPas

[0203] Solid content: 100%

[0204] Polyisocyanate 9:

[0205] An isophorone diisocyanate (IPDI) polyisocyanate containing isocyanurate structures was prepared through catalytic trimerization of IPDI in accordance with Example 2 of EP-A-0003 765. The reaction was deactivated at an NCO content of the crude mixture of 30.1% by addition of an equimolar amount of dibutyl phosphate, based on the amount of catalyst used, and stirring at 80 °C for 30 minutes. Unreacted IPDI was then separated off by thin-film distillation at a temperature of 170 °C and a pressure of 0.3 mbar, and the solid resin obtained was diluted with butyl acetate (BA). The product had the following characteristics and composition:

[0206] NCO content: 11.9%

[0207] monomeric IPDI: 0.28%

[0208] Viscosity (23 °C) 620 mPas

[0209] Solid content: 70%

[0210] Formulations: 2024PF30135-Foreign Countries

[0211] 21

[0212] Component AF: Setalux DA 870 BA was mixed with Byk 141 (delivered form), Byk 331 (10 % solution in BA, Tinuvin 292 (50 % solution in BA), and Tinuvin 1130 (50 % solution in BA). The mixture was diluted with a solution of MPA: Xylene: BA 1:1:1.

[0213] Component BF: 24.43 g of Polyisocyanate 1 was diluted with 10.00 g of a solution of BA and xylene 1:1.

[0214] Component AF and BF were poured into a container in an NCO to OH ratio of 1:1 and mixed by hand for 1 minute. The formulations were applied on panels depending on the test to be carried out, with a coating knife. The panels were dried at room temperature, or 30 minutes at 60 °C, or 30 minutes at 80 °C, or 30 minutes at 140 °C. The dry film thickness after curing was approximately 50 μm.

[0215] Formulation examples are shown in Table 1 to Table 4, application results are shown in Tables 5 to Table 8:

[0216] Table 1. Formulation Examples 1-4:

[0217] Component AF Solid content Example 1 Example 2 Example 3 Example 4 Setalux DA 870 BA 70% BA 68,41 67,81 64.2 63,8 Byk 141 100% 0,36 0,36 0,36 0,36 Byk 331 10% BA 2,17 2,17 2,17 2,17 Addokat 201 1% BA 2,18 2,18 2,18 2,18 Tinuvin 292 50% BA 1,44 1,44 1,44 1,44 Tinuvin 1130 50% BA 2,89 2,89 2,89 2,89 MPA / Xylol / BA 1:1:1 31,98 34,05 44,7 44,73 Component BF

[0218] Polyisocyanate 3 60% BA 40,57

[0219] Polyisocyanate 4 60% BA 41,28

[0220] Polyisocyanate 5 80% BA 34,6 Polyisocyanate 6 80% BA 34,9

[0221]

[0222] 2024PF30135-Foreign Countries

[0223] 22

[0224] Table 2. Formulation Examples 5-8:

[0225] Component AF Solid content Example 5 Example 6 Example 7 Example 8 Setalux DA 870 BA 70% BA 69,75 68,51 63,46 68,04 Byk 141 100% 0,36 0,36 0,36 0,36 Byk 331 10% BA 2,17 2,17 2,17 2,17 Addokat 201 1% BA 2,18 2,18 2,18 2,18 Tinuvin 292 50% BA 1,44 1,44 1,44 1,44 Tinuvin 1130 50% BA 2,89 2,89 2,89 2,89 MPA / Xylol / BA 1:1:1 47,81 47,88 37,78 37,78 Component BF

[0226] Polyisocyanate 7 100% 23.41 24,60 Polyisocyanate 8 100% 23.57

[0227] Polyisocyanate 9 70% BA 39.73 10,55

[0228]

[0229] 2024PF30135-Foreign Countries

[0230] 23

[0231] Table 3. Formulation Examples 9-12:

[0232] Component AF Solid content Example 9 Example 10 Example 11 Example 12 Setalux DA

[0233] 70% BA 68,41 67,81 64.2 63,8 870 BA

[0234] Byk 141 100% 0,36 0,36 0,36 0,36 Byk 331 10% BA 2,17 2,17 2,17 2,17 Addokat 201 1% BA - - - - Tinuvin 292 50% BA 1,44 1,44 1,44 1,44 Tinuvin 1130 50% BA 2,89 2,89 2,89 2,89 MPA / Xylol / BA

[0235] 31,98 34,05 44,7 44,73 1:1:1

[0236] Component BF

[0237] Polyisocyanate

[0238] 60% BA 40,57

[0239] 3

[0240] Polyisocyanate

[0241] 60% BA 41,28

[0242] 4

[0243] Polyisocyanate

[0244] 80% BA 34,6 5

[0245]

[0246] 2024PF30135-Foreign Countries

[0247] 24

[0248] Polyisocyanate

[0249] 80% BA 34,9 6

[0250]

[0251] Table 4. Formulation Examples 13-16.

[0252] Component AF Solid content Example 13 Example 14 Example 15 Example 16 Setalux DA 870 BA 70% BA 69,75 68,51 63,46 68,04 Byk 141 100% 0,36 0,36 0,36 0,36 Byk 331 10% BA 2,17 2,17 2,17 2,17 Addokat 201 1% BA - - - - Tinuvin 292 50% BA 1,44 1,44 1,44 1,44 Tinuvin 1130 50% BA 2,89 2,89 2,89 2,89 MPA / Xylol / BA

[0253] 47,81 47,88 37,78 37,78 1:1:1

[0254] Component BF

[0255] Polyisocyanate 7 100% 23.41 24,60 Polyisocyanate 8 100% 23.57

[0256] Polyisocyanate 9 70% BA 39.73 10,55

[0257]

[0258] 2024PF30135-Foreign Countries

[0259] 25

[0260] Table 5. Application results / coating properties examples 1-4 containing catalyst.

[0261] Example 1 Example 2 Example 3 Example 4

[0262] Viscosity DIN Cup 4 mm @ r.t. (s)

[0263] 0 h 20 22 20 20 2 h >60 >60 >60 >60 Drying Behaviour (min)

[0264] RTT1 30 35 25 30 RTT4 110 160 230 260 30 min, 60 °C T4 direct direct direct direct Hardness (s)

[0265] RT Id 133 132 101 110 30 min, 60 °C Id 153 177 122 121 Solvent resistance: (Xy / MPA / EA / Ac), 5 min test

[0266] RT 7d 2234 2234 0034 0024 30 min, 60 °C 7d 1224 2224 0023 0023 Acid / Base resistance 10% H2SO4 / 10% NaOH, 30 min, 60°C, 7d, 24h test

[0267] r.t., 7d 0 / 0 0 / 0 0 / 0 0 / 0 30, 60 °C 7d 0 / 0 0 / 0 0 / 0 0 / 0

[0268]

[0269] 2024PF30135-Foreign Countries

[0270] 26

[0271] Table 6. Application results / coating properties examples 5-8 containing catalyst.

[0272] Example 5 Example 6 Example 7 Example 8

[0273] Viscosity DIN Cup 4 mm @ r.t. (s)

[0274] 0 h 17 17 19 18 2 h 43 37 21 25 Drying Behaviour (min)

[0275] RTT1 70 60 30 45 RTT4 > 8h >8h 480 >8h 30 min, 60 °C T4 180 110 direct direct Hardness (s)

[0276] RT Id 56 31 59 51 30 min, 60 °C Id 96 66 112 81 Solvent resistance: (Xy / MPA / EA / Ac), 5 min test

[0277] RT 7d 2234 2123 5555 2135 30 min, 60 °C 7d 2124 2123 5555 2235 Acid / Base resistance 10% H2SO4 / 10% NaOH, 30 min, 60°C, 7d, 24h test

[0278] r.t., 7d 0 / 0 0 / 0 0 / 0 0 / 0 30, 60 °C 7d 0 / 0 0 / 0 0 / 0 0 / 0

[0279]

[0280] 2024PF30135-Foreign Countries

[0281] 27

[0282] Table 7. Application results / coating properties examples 9-12 without catalyst.

[0283] Example 9 Example 10 Example 11 Example 12

[0284] Viscosity DIN Cup 4 mm @ r.t. (s)

[0285] 0 h 20 22 20 18 2 h 32 41 31 26 Drying Behaviour (min)

[0286] RTT1 20 30 30 35 RTT4 160 170 310 360 30 min, 60 °C T4 direct direct direct direct Hardness (s)

[0287] RT Id 136 97 97 91 30 min, 60 °C Id 146 135 135 132 Solvent resistance: (Xy / MPA / EA / Ac), 5 min test

[0288] RT 7d 2234 2234 1035 0035 30 min, 60 °C 7d 1224 2224 0024 0024 Acid / Base resistance 10% H2SO4 / 10% NaOH, 30 min, 60°C, 7d, 24h test

[0289] r.t., 7d 0 / 0 1 / 0 0 / 0 0 / 0 30, 60 °C 7d 0 / 0 0 / 0 0 / 0 0 / 0

[0290]

[0291] 2024PF30135-Foreign Countries

[0292] 28

[0293] Table 8. Application results / coating properties examples 13-16 without catalyst.

[0294] Example 13 Example 14 Example 15 Example 16

[0295] Viscosity DIN Cup 4 mm @ r.t. (s)

[0296] 0 h 17 17 19 18 2 h 22 23 20 21 Drying Behaviour (min)

[0297] RT T1 70 60 30 45 RT T4 > 8h >8h 480 >8h 30 min,

[0298] 240 200 direct direct 60 °C T4

[0299] Hardness (s)

[0300] RT Id 49 31 79 38 30 min,

[0301] 97 66 123 94 60 °C Id

[0302] Solvent resistance: (Xy / MPA / EA / Ac), 5 min test

[0303] RT 7d 2234 2123 4455 2135 30 min,

[0304] 2124 2123 3355 2235 60 °C 7d

[0305] Acid / Base resistance 10% H2SO4 / 10% NaOH, 30 min, 60°C, 7d, 24h test

[0306] r.t., 7d 0 / 0 0 / 0 0 / 0 0 / 0 30, 60 °C

[0307] 0 / 0 0 / 0 0 / 0 0 / 0 7d

[0308]

[0309] Discussion of the results

[0310] As apparent from the descriptions of polyisocyanat 1 and 2, isohexide diisocyanates can be oligomerized by catalytic means to obtain polyisocyanates. However, due to their high melt-viscosities, the polyisocyanates obtained cannot be purified via technically relevant methods like thin-film -evaporation. Furthermore, the solubility of polyisocyanates which are solely based on isohexide based diisocyanates is limited and results in precipitation of the material (cf. example 1). For industrial application however, 2024PF30135-Foreign Countries

[0311] 29

[0312] it is necessary to free the reaction mixture from excess monomeric diisocyanates and to get soluble polyisocyanates.

[0313] As visible from the data summarized in Table 5, coating formulations based on PICs that contain isohexide diisocyanates (examples 1,2,3 and 4) show significantly faster chemical drying, as apparent by their viscosity increase, than coatings based on standard aliphatic PICs (Table 6, examples 5 to 8). Furthermore, they also surpass the state-of-the-art regarding physical drying properties of coatings containing cycloaliphatic PICs like IPDI based PICs (example 7), reaching T4 drying at room temperature within a time frame of 110 to 420 min. A coating based on typical blend of HDI / IPDI PICs (example 8) was tested, which shows a compromise between chemical- and physical drying properties, which is however not comparable with the inventive examples neither in physical-or chemical drying speed. Additionally, the pendulum hardness of the coatings after one day at low temperatures (r.t. and 60°C) differ significantly from each other. While coatings based on HDI, PDI, IPDI and HDI / IPDI polyisocyanates blend (examples 5-8) only develop low to moderate hardness one day after curing at r.t. or for 30 min at 60°C, coatings containing isohexide PICs show a significant improvement of hardness properties. The coating performance regarding solvent resistance and acid / base resistance is in all cases on a high level and comparable.

[0314] Formulations discussed above were also tested without a catalyst, see Table 7 (examples 9-12) and (examples 13-16). Even without a catalyst, coating performance for the inventive isohexide PIC containing coatings (examples 9-12) is superior to non-isohexide PIC containing coatings (examples 13-16). As evident from the measured viscosity increases and the drying times, only small differences can be observed between the catalyzed and non-catalyzed isohexide PIC based systems. On the other hand, standard aliphatic PICs show significantly slower chemical drying as well as longer physical drying times without a catalyst (examples 5-8 vs 13-16).

Claims

2024PF30135-Foreign Countries30Claims1. Composition comprisingA) a polyisocyanate composition comprising at least one isocyanurate structure and having a residual monomeric diisocyanate content of diisocyanates of components Al) and A2) of less than 1 % by weight, based on the total weight of the polyisocyanate composition, determined by gas chromatography in accordance with DIN EN ISO 10283:2007-11 with internal standard, obtainable or obtained by a process comprisingreacting an isocyanate composition, comprisingAl) (3R,3aR,6S,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan and / or (3S,3aR,6S,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan and / or (3R,3aR,6R,6aR)-3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan andA2) at least one diisocyanate of the general formula OCN-R-NCO, wherein R is a divalent linear or branched aliphatic residue containing at least 4 carbon atoms, optionally in the presence of at least one catalyst A3), to form a raw polyisocyanate composition,and subjecting the raw polyisocyanate composition to a distillation, preferably to a thin film distillation, a short path distillation and / or a falling film distillation, in order to at least partially remove unreacted moieties of components Al) and A2) and to obtain the polyisocyanate composition comprising at least one isocyanurate structure,wherein the weight ratio of (3R,3aR,6S,6aR)-3,6-diyl-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-, (3S,3aR,6S,6aR)-3,6-diyl-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan- and / or (3R,3aR,6R,6aR)- 3,6-diisocyanato-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-structures in polyisocyanate composition A) to structures -R- in polyisocyanate composition A), wherein R corresponds to the organic residue R in the general formula OCN-R-NCO of component A2), is > 2.5:1 to < 8:1, wherein the fraction of these structures in the polyisocyanate composition is determined using NMR spectroscopic analysis as defined in the description,andB) at least one NCO-reactive compound,wherein components A) and B) are used in amounts corresponding to an equivalent ratio of isocyanate groups to isocyanate-reactive groups of 2: 1 to 0.5 to 1.2024PF30135-Foreign Countries312. Composition according to claim 1, wherein the at least one diisocyanate of the general formula OCN-R-NCO is selected from the group consisting of pentamethylene diisocyanate (PDI), hexamethylene diisocyanate (HDI), 2-methylpentane 1,5 -diisocyanate, 2,2,4-trimethylhexane 1,6- diisocyanate, 2,4,4-trimethylhexane 1,6-diisocyanate and 4-isocyanatomethyloctane 1,8- diisocyanate.

3. Composition according to claims 1 or 2, wherein component A) is characterized in that it has a residual monomeric diisocyanate content of diisocyanates of components Al) and A2) of less than 0.5 % by weight, preferably less than 0.1 % by weight, based on the total weight of component A), determined by gas chromatography in accordance with DIN EN ISO 10283:2007-11 with internal standard.

4. Composition according to any of claims 1 to 3, wherein component A) is characterized by a NCO content of from 5.8 to 25.9% by weight, preferably from 7.8 to 24.9% by weight, particularly preferably from 9.7 to 23.9% by weight, based on the total weight of component A), determined in accordance with DIN EN ISO 11909:2007-05.

5. Composition according to any of claims 1 to 4, wherein the at least one NCO-reactive compound is selected from the group consisting of low molecular weight diols, triols and tetraols, short-chain polyamines, polyaspartic esters, polythiols, polyether polyols, polyester polyols, polyurethane polyols, polysiloxane polyols, polycarbonate polyols, polyether polyamines, polybutadiene polyols, polyacrylate polyols and polymethacrylate polyols, and the copolymers thereof.

6. Composition according to any of claims 1 to 5, wherein the composition comprises at least on catalyst, which catalyzes the reaction of components A) and B) (component C)).

7. Composition according to any of claims 1 to 5, wherein the composition does not comprise a catalyst / s, which catalyze the reaction of components A) and B).

8. Use of a composition according to any of claims 1 to 7 or use of a polyisocyanate composition comprising at least one isocyanurate structure according to component A) of any of claims 1 to 7 in the synthesis of coating compositions, adhesives or sealants.

9. Coating composition, adhesive or sealant obtainable by the use according to claim 8.2024PF30135-Foreign Countries3210. Use according to claim 8 or coating composition, adhesive or sealant according to claim 9, wherein the coating composition, adhesive or sealant is a one-component or a two-component system.

11. Substrate comprising a coating composition, an adhesive or a sealant according to claim 9 or 10, wherein the coating composition, adhesive or sealant is uncured, partially cured or fully cured.

12. Method for coating a substrate comprising the steps:i) providing an optionally pretreated substrate,ii) applying the coating composition according to claim 9 or 10 to the substrate, andiii) partially or fully curing of the coating composition.

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