Polyisocyanate Mixture

Abstract

The present invention relates to a polyisocyanate mixture, a process for its preparation, and its use as a starting component in the production of polyurethane plastics. The present invention further relates to a coating agent containing the polyisocyanate mixture and a substrate coated with said coating agent.

Description

[Technical Field]

[0001] The present invention relates to a polyisocyanate mixture and a process for its preparation. The present invention further relates to the use of the polyisocyanate mixture, to a coating composition containing the polyisocyanate mixture, and to a substrate coated with the coating composition. [Background technology]

[0002] Two-component polyurethane coatings (2K-PUR) have become important for many different applications due to their exceptional technical properties. The crosslinker component used in light-fast, non-yellowing 2K-PUR coatings is generally a polyisocyanate based on a linear aliphatic or cycloaliphatic diisocyanate.

[0003] Polyisocyanates based on 1,6-diisocyanatohexane (hereinafter referred to as HDI) are used in the majority of 2K PUR coating applications today. Even at low temperatures, they produce elastic coatings that are resistant to chemical and mechanical stress.

[0004] The trend toward more sustainable products has also led to an increased demand for bio-based raw materials in polyurethanes in recent years. This has led to the development of polyisocyanate crosslinkers based on biomass-derived 1,5-diisocyanatopentane (hereinafter also referred to as PDI) (see, for example, EP 3271432 and WO 2016 / 169810). PUR coatings and adhesives made with bio-based PDI polyisocyanates have similar performance levels to, and in some applications even superior to, those crosslinked with comparable petrochemical-based HDI polyisocyanates.

[0005] However, a significant drawback of PDI polyisocyanates is that they exhibit higher viscosities at comparable oligomer distributions compared to their HDI counterparts (M. Widemann et al., ACS Sustainable Chem. Eng. 2018, 6, 9753-9759; DOI: http: / / dx.doi.org / 10.1021 / acssuschemeng.8b00758), and their processing generally requires larger amounts of organic solvents. However, particularly in sustainable coating and adhesive systems, it is desirable to have as low a proportion of volatile organic components as possible.

[0006] U.S. Patent Application Publication No. 2012 / 0016073 describes a method for producing low-viscosity allophanate polyisocyanates based on monoalcohols containing ether or polyether groups, which can be used as reactive diluents for relatively high-viscosity polyisocyanates. This document generally lists polymethylene diisocyanates with 2 to 6 methylene units as suitable starting diisocyanates for this process, and HDI as the preferred starting diisocyanate. The production of HDI allophanate polyisocyanates requires a complex catalyst system consisting of a bismuth compound, preferably bismuth tricarboxylate, and alkali metal and alkaline earth metal salts as cocatalysts. However, bismuth catalysts have the general drawback of undergoing decomposition during long-term storage, especially on exposure to sunlight, which generally results in brown discoloration or even the precipitation of black particles in the polyisocyanate (D. Guhl, FAPU 49, 30-33 (2008), DOI: 10-1386-08-EPJ-2-2008-d.indd).

[0007] In Polymers 2021, 13, 1255 (DOI: https: / / doi.org / 10.3390 / polym13081255), Caillol et al. describe the commercial product Tolonate™ X FLO 100 from Vencorex, manufactured according to U.S. Patent Application Publication No. 2012 / 0016073, as a partially biobased polyisocyanate with an allophanate structure based on HDI and ethoxylated palmitic acid as a synthetic component for thermosetting polyurethanes. The aforementioned drawbacks apply to the manufacture of this product.

[0008] Furthermore, in the case of HDI allophanates, even a small amount of residual urethane structure that may still be present due to incomplete allophanatization causes turbidity in the product.

[0009] The prior art also does not provide guidance to the possible use of PDI to prepare the corresponding allophanates.

[0010] Therefore, there remained a need to provide low-viscosity allophanate polyisocyanates that remain completely clear and haze-free, even during long-term storage, regardless of the catalyst used and regardless of the residual urethane content. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] European Patent Application Publication No. 3271432 [Patent Document 2] International Publication No. 2016 / 169810 [Patent Document 3] US Patent Application Publication No. 2012 / 0016073 [Non-patent literature]

[0012] [Non-Patent Document 1] M.Widemann et al.,ACS Sustainable Chem.Eng.2018,6,9753-9759;DOI:http: / / dx.doi.org / 10.1021 / acssuschemeng.8b00758 [Non-patent document 2] D.Guhl,FAPU 49,30-33(2008),DOI:10-1386-08-EPJ-2-2008-d.indd [Non-patent document 3] Caillol et al., Polymers 2021,13,1255(DOI:https: / / doi.org / 10.3390 / polym13081255) Summary of the Invention [Problem to be solved by the invention]

[0013] The object of the present invention is to provide low-viscosity allophanate polyisocyanates which remain completely clear and haze-free, even during long periods of storage, regardless of the catalyst used and regardless of the residual urethane content. [Means for solving the problem]

[0014] Considering this requirement, the present invention provides a compound represented by the general formula (I): [ka] (In the formula, R represents an optionally substituted linear or branched saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic group having (6 to 22)-p carbon atoms; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; n is an integer from 1 to 12, m is an integer from 1 to 10, and p is 0 or 1) The present invention provides a polyisocyanate mixture containing at least one polyisocyanate of the formula:

[0015] The present invention also provides A) a diisocyanate component containing at least 1,5-diisocyanatopentane, B) General formula (II) [ka] (In the formula, R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic group having (6 to 22)-p carbon atoms, which may in each case be substituted; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; m is an integer from 1 to 10, and p is 0 or 1) with at least one alcohol of the formula (I).

[0016] Surprisingly, it has now been found that PDI can be very easily converted into low-viscosity, light-colored allophanate polyisocyanates with ethoxylated fatty alcohols and / or fatty acids, even using known allophanation catalysts, such as zinc or zirconium catalysts. A particular advantage of using PDI is that, compared to similarly prepared HDI derivatives, PDI allophanate polyisocyanates have significantly greater crystallization stability, even when incompletely allophanated, so that the PDI polyisocyanates according to the invention remain completely transparent and clear, even with a relatively high residual urethane content.

[0017] According to the present invention, the terms "comprising" and "containing" are to be understood to preferably mean "consisting essentially of", and particularly preferably "consisting of". The claims and further embodiments recited herein may be combined as desired, unless the context clearly indicates otherwise.

[0018] As used herein, "at least one" refers to one or more, e.g., two, three, four, five, six, seven, eight, nine, or more. In reference to the components of the compounds described herein, this number does not refer to the absolute number of molecules, but rather to the nature of the component. Thus, "at least one polyisocyanate" should be understood to mean, for example, that only one type of polyisocyanate or two or more different types of polyisocyanates may be present, without specifying the amount of each individual compound.

[0019] In the present case, polyisocyanate mixtures according to the invention containing at least one polyisocyanate of general formula (I) should generally be understood to mean that they may and preferably contain not only compounds of general formula (I) where n=1, but also one or more compounds of formula (I) where n=2 to 12, preferably formed from PDI and alcohols of general formula (II), as well as further oligomers typically based on PDI, such as PDI isocyanurates.

[0020] It is particularly preferred if the polyisocyanate mixtures according to the invention contain a proportion of allophanate structures determinable by NMR spectroscopy of more than 60 mol %, preferably more than 65 mol %, particularly preferably more than 70 mol %, and even more preferably more than 75 mol %, based on the sum of the molar proportions of allophanate, isocyanurate, urethane and uretdione structures.

[0021] Numerical values ​​specified herein without decimal points in each case refer to the full value specified to one decimal point, thus, for example, "99%" represents "99.0%".

[0022] Numerical ranges given in the format "of x to y / x to y" are inclusive of the recited values. When two or more preferred numerical ranges are given in this format, it is understood that all ranges resulting from combining the various limits are also encompassed.

[0023] The term "aliphatic" is defined herein to mean a non-aromatic hydrocarbon group that is saturated or unsaturated.

[0024] The term "araliphatic" is defined herein to mean an aliphatic hydrocarbon group that is saturated or unsaturated and has at least one aromatic substituent.

[0025] The terms "alicyclic" or "cycloaliphatic" are defined herein to mean optionally substituted carbocyclic or heterocyclic compounds or units that are not aromatic (e.g., cycloalkanes, cycloalkenes, or oxa-, thia-, aza-, or thiazacycloalkanes). Particular examples are the cyclohexyl group, the cyclopentyl group, and their N- or O-heterocyclic derivatives, such as pyrimidine, pyrazine, tetrahydropyran, or tetrahydrofuran.

[0026] When a group or compound is disclosed as being "optionally substituted" or "substituted," suitable substituents are -F, -Cl, -Br, -I, -OH, -OCH3, -OCH2CH3, -O-isopropyl or -On-propyl, -OCF3, -CF3, -SC 1-6-alkyl and / or linear or branched aliphatic and / or alicyclic structural units having 1 to 12 carbon atoms (possibly via pendant heteroatoms) which in each case function as replacements for carbon-bonded hydrogen atoms of the respective molecules. Preferred substituents are halogens (especially -F, -Cl), C 1-6 Alkoxy (especially methoxy and ethoxy), hydroxyl, trifluoromethyl and trifluoromethoxy, which in each case function as a replacement for a carbon-bonded hydrogen atom of the respective molecule. DETAILED DESCRIPTION OF THE INVENTION

[0027] In a first preferred embodiment, the polyisocyanate mixture according to the invention has an NCO content of 6.0% to 18.0% by weight, preferably 8.0% to 16.0% by weight, particularly preferably 10.0% to 15.0% by weight, based on the total weight of the polyisocyanate mixture, and / or a residual monomer content, determined by gas chromatography with an internal standard in accordance with DIN EN ISO 10283:2007-11, of less than 0.14% by weight, preferably less than 0.12% by weight, particularly preferably less than 0.10% by weight, based on the total weight of the polyisocyanate mixture.

[0028] In a further preferred embodiment, the polyisocyanate mixture according to the invention has a viscosity of 250 s at 23° C. of less than 500 mPas, preferably less than 400 mPas, particularly preferably less than 300 mPas. -1 The viscosity is measured according to DIN EN ISO 3219:1994-10 at a shear rate of 1000 rpm.

[0029] General formula (I) [ka] (In the formula, R represents an optionally substituted linear or branched saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having (8 to 20)-p, particularly preferably (10 to 18)-p, very particularly preferably (12 to 14)-p, carbon atoms, R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; n is an integer from 1 to 12, m is an integer from 1 to 7, particularly preferably an integer from 2 to 5, very particularly preferably an integer from 2 to 4, and p is 0 or 1) is preferred.

[0030] The diisocyanate component A) used to prepare the polyisocyanate mixtures according to the invention contains at least 1,5-diisocyanatopentane (also referred to herein as pentamethylene diisocyanate or PDI), which is obtained by various routes, for example by phosgenation in the liquid or gas phase, or by phosgene-free routes, for example by thermal urethane cleavage proceeding from 1,5-diaminopentane, which is preferably obtained by biotechnological means by decarboxylation of the naturally occurring amino acid lysine.

[0031] In addition to 1,5-diisocyanatopentane, further diisocyanates having aliphatically, cycloaliphatically, araliphatically and / or aromatically bound isocyanate groups can also be used simultaneously in diisocyanate component A), which can likewise be obtained by phosgenation or by a phosgene-free route. These are in particular those in the molecular weight range from 140 to 400, such as 1,4-diisocyanatobutane, 1,6-diisocyanatohexane (HDI), 2-methyl-1,5-diisocyanatopentane, 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-trimethyl-1,6-diisocyanatohexane, 1,10-diisocyanatodecane, 1,3- and 1,4-diisocyanatocyclohexane, 2,4- and 2,6-diisocyanato-1-methylcyclohexane, 1,3- and 1,4-bis(isocyanatomethyl)cyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanatomethyl). isocyanate, IPDI), 4,4'-diisocyanatodicyclohexylmethane, 2,4'-diisocyanatodicyclohexylmethane, 1-isocyanato-1-methyl-4(3)isocyanatomethylcyclohexane, bis(isocyanatomethyl)norbornane, 1,3- and 1,4-bis(isocyanatomethyl)benzene (XDI), 1,3- and 1,4-bis(2-isocyanatoprop-2-yl)benzene (TMXDI), 2,4- and 2,6-diisocyanatotoluene (TDI), 2,4'- and 4,4'-diisocyanatodiphenylmethane (MDI), 1,5-diisocyanatonaphthalene or any desired mixture of such diisocyanates.

[0032] These diisocyanates, for optional simultaneous use in diisocyanate component A) during the preparation of the polyisocyanate mixtures according to the invention, are used, if at all, in amounts of up to 40% by weight, preferably up to 30% by weight, particularly preferably up to 20% by weight, very particularly preferably up to 10% by weight, based on the total amount of diisocyanates used.

[0033] In a further preferred embodiment, diisocyanate component A) uses at least 60% by weight, preferably at least 70% by weight, particularly preferably at least 80% by weight, and very particularly preferably at least 90% by weight, of 1,5-pentamethylene diisocyanate, based on diisocyanate component A), and optionally further diisocyanates having aliphatically, cycloaliphatically, araliphatically, and / or aromatically bound isocyanate groups in an amount of up to 40% by weight, preferably up to 30% by weight, particularly preferably up to 20% by weight, and very particularly preferably up to 10% by weight, based on diisocyanate component A).

[0034] A further preferred embodiment is A) at least 1,5-diisocyanatopentane, B) General formula (II) [ka] (In the formula, R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic group having (6 to 22)-p carbon atoms, which may in each case be substituted; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; m is an integer from 1 to 10, and p is 0 or 1) with at least one alcohol of the formula:

[0035] The alcohol component B) used in the process according to the invention is of the general formula (II) [ka] (In the formula, R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having in each case (6 to 22)-p, preferably (8 to 20)-p, particularly preferably (10 to 18)-p and very particularly preferably (12 to 14)-p carbon atoms, which may be substituted, R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; and m is an integer from 1 to 10, preferably an integer from 1 to 7, particularly preferably an integer from 2 to 5, very particularly preferably an integer from 2 to 4, and p is 0 or 1) At least one alcohol.

[0036] These alcohols are, for example, those of the general formula (III) [ka] (In the formula, R 1 represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having in each case 6 to 22, preferably 8 to 20, particularly preferably 10 to 18, very particularly preferably 12 to 14 carbon atoms, which may be substituted the known alkoxylation products of fatty alcohols of and / or general formula (IV) [ka] (In the formula, R 2 represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having in each case 5 to 21, preferably 7 to 19, particularly preferably 9 to 17, very particularly preferably 11 to 13 carbon atoms, which may be substituted is a fatty acid.

[0037] In the case of the fatty alcohol of the above general formula (III), in general formula (I) and general formula (II), p is 0, and R 1 represents R, and R 1 The above-mentioned preferences are included for the groups R. 1 and R includes, by way of example, groups derived from fatty alcohols, which are listed below as suitable, preferred and particularly preferred.

[0038] In the case of the fatty alcohol of the above general formula (IV), in general formula (I) and general formula (II), p is 1, and R 2 represents R, and R 2 The above-mentioned preferences are included for the groups R. 2 and R includes, by way of example, groups derived from the fatty acids listed below as suitable, preferred and particularly preferred.

[0039] Fatty alcohols suitable for alkoxylation include, for example, 1-hexanol (caproic alcohol), 1-heptanol (enanthic alcohol), 1-octanol (caprylic alcohol), 1-nonyl alcohol (pelargonic alcohol), 1-decanol (capric alcohol), 1-dodecanol (lauryl alcohol), 1-tetradecanol (myristyl alcohol), 1-hexadecanol (cetyl alcohol), 1-heptadecanol (margaryl alcohol), 1-octadecanol (stearyl alcohol), 1-eicosanol (arachidyl alcohol), 1-docosanol (behenyl alcohol), 1-tetracosanol (lignoceryl alcohol), 1-hexacosanol (ceryl alcohol), 1-octacosanol (montanyl alcohol), 1-triacontanol (melissyl alcohol), cis-9-hexadecen-1-ol (paprika alcohol), 1-octacosanol (montanyl alcohol), 1-triacontanol (melissyl alcohol), cis-9-hexadecen-1-ol (paprika alcohol), 1-octacosanol (montanyl alcohol), 1-tria ... Suitable fatty acids include, for example, hexadecyl alcohol, cis-9-octadecen-1-ol (lumitrail alcohol), cis-9-octadecen-1-ol (oleyl alcohol), trans-9-octadecen-1-ol (elaidyl alcohol), cis-11-octadecen-1-ol, cis,cis-9,12-octadecadien-1-ol (linoleyl alcohol) and 6,9,12-octadecatrien-1-ol (γ-linolenyl alcohol). These include xanoic acid (caproic acid), heptanoic acid (enanthic acid), octanoic acid (caprylic acid), nonanoic acid (pelargonic acid), decanoic acid (capric acid), undecanoic acid, dodecanoic acid (lauric acid), tridecanoic acid, tetradecanoic acid (myristic acid), pentadecanoic acid, hexadecanoic acid (palmitic acid), heptadecanoic acid (margaric acid), octadecanoic acid (stearic acid), nonadecanoic acid, eicosanoic acid (arachinic acid), heneicosanoic acid and docosanoic acid (behenic acid), cis-9-octadecenoic acid (oleic acid) and cis-13-docosenoic acid (erucic acid).

[0040] Fatty alcohols and fatty acids produced using vegetable and animal fats and oils are preferred.

[0041] Particularly preferred fatty alcohols for preparing alcohol component B) include 1-decanol, 1-dodecanol, 1-tetradecanol, and 1-octadecanol, with 1-dodecanol and 1-tetradecanol being very particularly preferred. Particularly preferred fatty acids include decanoic acid, dodecanoic acid, tetradecanoic acid, and hexadecanoic acid, with dodecanoic acid and tetradecanoic acid being very particularly preferred. Suitable compounds for preparing alcohol component B) by alkoxylation of the listed fatty alcohols and / or fatty acids include any desired alkylene oxide having 2 to 12 carbon atoms, such as ethylene oxide, propylene oxide, 1,2-epoxybutane, 1,2-epoxyhexane, 1,2-epoxyoctane, or 1,2-epoxydodecane, which may be used in any desired order or mixture in the alkoxylation reaction. Preferred alkylene oxides are those having 2 to 4 carbon atoms. Particularly preferred alkylene oxides for preparing alcohol component B) are ethylene oxide and propylene oxide.

[0042] The number of carbon atoms of the group R' or R" in general formula (I) is, by way of example and preferably, derived from the alkylene oxides listed above. Thus, R' and R" in general formula (I) and / or formula (II) independently represent hydrogen or an aliphatic group preferably having 1 to 2 carbon atoms, and at least one of the groups R' and R" represents hydrogen.

[0043] Suitable alcohol components B) for preparing the polyisocyanate mixtures according to the invention include, in particular, the alkoxylation products of the listed fatty acids and / or fatty alcohols, which have on average 1 to 10, preferably 1 to 7, particularly preferably 2 to 5, and very particularly preferably 2 to 4 alkylene oxide units. The preferred integers m according to the invention in the general formulae (I) and (II) are derived as an average from the numbers and ranges of numbers listed above.

[0044] In a further preferred embodiment, the alcohol component B) is selected from alkoxylation products having on average 1 to 10, preferably 1 to 7, particularly preferably 2 to 5, very particularly preferably 2 to 4 alkylene oxide units, which alkylene oxide units preferably comprise or consist of ethylene oxide and / or propylene oxide units.The preferred integers m of the present invention in the general formulae (I) and (II) are derived as an average from the numbers and ranges of numbers listed above.

[0045] The alcohol component B) preferably has a pH, measured in a 1% aqueous solution of the respective alcohol component B), of 4.0 to 8.0, preferably 4.5 to 7.5, particularly preferably 5.0 to 7.0, and / or a total content of alkali metal cations of at most 100 ppm, preferably 1 to 70 ppm, particularly preferably 2 to 50 ppm.

[0046] In addition to the listed alkoxylation products of fatty alcohols and / or fatty acids, component B) may contain small amounts of further alcohol compounds.

[0047] These include, for example, monoalcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomeric pentanols, hexanols, octanols and nonanols, n-decanol, n-dodecanol, n-tetradecanol, n-hexadecanol, n-octadecanol, cyclohexanol, the isomeric methylcyclohexanols, hydroxymethylcyclohexane, 3-methyl-3-hydroxymethyloxetane, benzyl alcohol, phenol, the isomeric cresols, octylphenol, nonylphenol and naphthol, furfuryl alcohol and tetrahydrofurfuryl alcohol, unbranched aliphatic diols such as 1,2-ethanediol. , 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol and 1,8-octanediol, alicyclic diols such as 1,2- and 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 4,4'-(1-methylidene)biscyclohexanol, triols such as 1,2,3-propanetriol, 1,1,1-trimethylolethane, 1,2,6-hexanediol, 1,1,1-trimethylolpropane, and 1,3,5-tris(2-hydroxyethyl)isocyanurate, tetrafunctional alcohols such as 2,2-bis(hydroxymethyl)-1,3-propanediol or any mixture of such alcohols.

[0048] If used, the process according to the invention uses these further alcohol compounds in an amount of at most 25% by weight, preferably at most 20% by weight, particularly preferably at most 15% by weight, based on the amount of alkoxylation product of fatty alcohols and / or fatty acids used.

[0049] Carrying out the process according to the invention comprises reacting a diisocyanate component A) containing at least 1,5-diisocyanatopentane with at least one alcohol component B), preferably at a temperature of from 40°C to 200°C, particularly preferably from 60°C to 180°C, and / or while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of preferably from 4:1 to 50:1, particularly preferably from 5:1 to 30:1, very particularly preferably from 10:1 to 25:1, to obtain an allophanate polyisocyanate.

[0050] The process of the present invention can be carried out as a thermally induced allophanatization without the use of a catalyst. However, it is preferable to use a suitable catalyst to promote the allophanatization reaction. These are conventional known allophanatization catalysts, such as metal carboxylates, metal chelates, or tertiary amines of the type described in GB-A-0994890 (page 2, lines 73-87), alkylating agents of the type described in U.S. Pat. No. 3,769,318 (column 6, lines 5-49), or strong acids such as those described by way of example in EP-A-0000194 (page 13, lines 27 to page 14, lines 1-18).

[0051] Suitable allophanatization catalysts are, in particular, zinc compounds such as zinc(II) stearate, zinc(II) n-octanoate, zinc(II) 2-ethyl-1-hexanoate, zinc(II) naphthenate or zinc(II) acetylacetonate, tin compounds such as tin(II) n-octanoate, tin(II) 2-ethyl-1-hexanoate, tin(II) laurate, dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dimaleate or dioctyl diacetate. Examples of catalysts include tin, zirconium compounds such as zirconium(IV) 2-ethyl-1-hexanoate, zirconium(IV) neodecanoate, zirconium(IV) naphthenate or zirconium(IV) acetylacetonate, aluminum tri(ethylacetoacetate), iron(III) chloride, potassium octoate, manganese, cobalt or nickel compounds, and strong acids such as trifluoroacetic acid, sulfuric acid, hydrogen chloride, hydrogen bromide, phosphoric acid or perchloric acid, or any desired mixtures of these catalysts.

[0052] Suitable but less preferred catalysts for the process of the present invention are also compounds which catalyze the trimerization of isocyanate groups as well as the allophanatization reaction to form isocyanurate structures. Such catalysts are described, for example, in EP-A-0 649 866, p. 4, line 7 to p. 5, line 15.

[0053] Preferred catalysts for the process according to the invention are zinc and / or zirconium compounds of the aforementioned kind, with very particular preference being given to the use of at least zinc(II) n-octoate, zinc(II) 2-ethyl-1-hexanoate and / or zinc(II) stearate, zirconium(IV) n-octoate, zirconium(IV) 2-ethyl-1-hexanoate and / or zirconium(IV) neodecanoate.

[0054] These catalysts, if used, are preferably used in the process according to the invention in amounts of 0.001% to 5% by weight, particularly preferably 0.005% to 1% by weight, based on the total weight of the co-reactants A) and B), and may be added before the start of the reaction or at any time during the reaction.

[0055] It is preferred if the process according to the invention does not use lead octoate as catalyst, and consequently polyisocyanate mixtures according to the invention which do not contain catalytic amounts of lead octoate, particularly preferably do not contain detectable amounts of lead octoate.

[0056] The method according to the present invention is preferably carried out without solvent.However, suitable solvents that are inert to the reactive groups of the starting components can also be used.Suitable solvents include, for example, conventional coating solvents known per se, such as ethyl acetate, butyl acetate, ethylene glycol monomethyl or monoethyl ether acetate, 1-methoxy-2-propyl acetate, 3-methoxy-n-butyl acetate, acetone, 2-butanone, 4-methyl-2-pentanone, cyclohexanone, toluene, xylene, chlorobenzene, white spirit, relatively highly substituted aromatics, such as Solvent naphtha, Solvesso®, Isopar®, Nappar®, Varsol® (ExxonMobil Chemical Central Europe, Cologne, Germany) and Shellsol® (Shell Deutschland Oil, Hamburg, Germany). GmbH), as well as 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.

[0057] In one possible embodiment, the process according to the invention comprises initially charging at least the PDI-containing starting component A) at a temperature of 20°C to 100°C, optionally under an inert gas, e.g., nitrogen, and optionally in the presence of a suitable solvent of the type enumerated. Subsequently, the alcohol component B) is added in the amount described above, and the reaction temperature for the urethanization can be adjusted by suitable means (heating or cooling) to a temperature of 30°C to 120°C, preferably 50°C to 100°C. After the urethanization reaction, i.e., when an NCO content theoretically corresponding to complete conversion of isocyanate and hydroxyl groups is reached, allophanatization can be initiated, for example, without the addition of a catalyst, by heating the reaction mixture to a temperature of 140°C to 200°C. However, it is preferred to use a suitable catalyst of the type described above to accelerate the allophanatization reaction; temperatures in the range of 60°C to 140°C, preferably 80°C to 120°C, are generally suitable, depending on the type and amount of catalyst used.

[0058] In a further possible embodiment of the process according to the invention, the catalyst for optional simultaneous use is already mixed with at least one of the PDI-containing starting component A) and / or alcohol component B) before the actual reaction begins. In this case, the urethane group formed as an intermediate undergoes spontaneous further reaction to give the desired allophanate structure. In this type of one-step reaction mode, the starting component A), which may contain a catalyst, may be initially charged under an inert gas, such as nitrogen, in the presence of a suitable solvent of the type optionally listed, at a temperature optimal for allophanation, generally in the range of 60°C to 140°C, preferably 80°C to 120°C, and is reacted with the alcohol component B), which may also contain a catalyst.

[0059] Alternatively, however, it is possible to add the catalyst to the reaction mixture at any desired time during the urethanization reaction. In this embodiment of the process according to the invention, a temperature in the range of 30°C to 120°C, preferably 50°C to 100°C, is generally established for the pure urethanization reaction to proceed prior to the addition of the catalyst. After the addition of a suitable catalyst, the allophanatization reaction is finally carried out at a temperature generally in the range of 60°C to 140°C, preferably 80°C to 120°C.

[0060] In the method according to the present invention, the progress of the reaction can be followed by titration measurement of the NCO content, for example, according to DIN EN ISO11909:2007-05. Preferably, the degree of allophanatization of the reaction mixture (i.e., the percentage of urethane groups intermediately formed from the hydroxyl groups of component B converted into allophanat groups, which can be calculated from the NCO content) is at least 80%, particularly preferably at least 90%, and very particularly preferably when the NCO content corresponding to complete allophanatization is reached or exceeded. In the case of a purely thermal reaction mode, this can be achieved, for example, by cooling the reaction mixture to room temperature. However, in the case of the preferred simultaneous use of the listed types of allophanatization catalysts, the reaction is generally terminated by adding a suitable catalyst poison, for example, an acid such as phosphoric acid, or an acid chloride such as benzoyl chloride or isophthaloyl dichloride.

[0061] The reaction mixture is then preferably freed from volatile components (excess monomeric diisocyanates, any solvents used, and, if no catalyst poisons have been used, any active catalyst) by thin-film distillation under high vacuum, for example at a pressure of less than 1.0 mbar, preferably less than 0.5 mbar, particularly preferably less than 0.2 mbar, under very mild conditions, for example at temperatures of 100 to 200°C, preferably 120 to 180°C.

[0062] The resulting distillate, which contains not only the unconverted monomeric starting diisocyanate and any solvent that may have been used at the same time, but also optionally the active catalyst if no catalyst poison was used, is readily usable for a new allophanatization in the process according to the invention.

[0063] In another embodiment of the process of the present invention, the volatile components mentioned are removed from the oligomerization product by extraction with a suitable solvent which is inert towards isocyanate groups, for example an aliphatic or cycloaliphatic hydrocarbon such as pentane, hexane, heptane, cyclopentane or cyclohexane.

[0064] Regardless of the type of after-treatment, the resulting products of the process according to the invention are clear, virtually colorless polyisocyanate mixtures having, in each case based on the solvent-free solid resin, a color number of less than 100 APHA, preferably less than 80 APHA, particularly preferably less than 60 APHA, and / or an NCO content of 6.0% to 18.0% by weight, preferably 8.0% to 16.0% by weight, particularly preferably 10.0% to 15.0% by weight, and / or a residual monomer content, determined by gas chromatography with an internal standard in accordance with DIN EN ISO 10283:2007-11, of less than 0.14% by weight, preferably less than 0.12% by weight, particularly preferably less than 0.10% by weight.

[0065] 250s at 23°C -1 The viscosity of the polyisocyanate mixtures according to the invention, measured in accordance with DIN EN ISO 3219:1994-10 at a shear rate of 1000 MPa, is preferably less than 500 mPas, particularly preferably less than 400 mPas and very particularly preferably less than 300 mPas.

[0066] The polyisocyanate mixtures according to the invention are completely resistant to crystallization and remain completely clear and haze-free even after 4 weeks of storage at 5°C.

[0067] In a further preferred embodiment, the polyisocyanate mixture according to the invention is 13 The polyisocyanate mixture according to the invention has a residual urethane content of less than 20 mol %, preferably less than 15 mol %, particularly preferably less than 10 mol %, based on the sum of the allophanate, urethane, isocyanurate and / or uretdione structures present, calculated from the integration of the C-NMR spectrum.

[0068] In this case, the "polyisocyanate mixture" according to the invention refers to an oligomer mixture resulting from random distribution, and therefore the polyisocyanate mixture according to the invention may also be called the polyisocyanate according to the invention. Thus, in a further embodiment, the invention provides a polyisocyanate of the general formula (I) [ka] (In the formula, R represents an optionally substituted linear or branched saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic group having (6 to 22)-p carbon atoms; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; n is an integer from 1 to 12, m is an integer from 1 to 10, and p is 0 or 1) This relates to polyisocyanates.

[0069] In a further embodiment, the present invention provides a method for producing a pharmaceutical composition comprising: A) a diisocyanate component containing at least 1,5-diisocyanatopentane, B) General formula (II) [ka] (In the formula, R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic group having (6 to 22)-p carbon atoms, which may in each case be substituted; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; m is an integer from 1 to 10, and p is 0 or 1) with at least one alcohol of the formula:

[0070] The same preferred embodiments as the other subjects of the present invention apply to the two preceding embodiments.

[0071] Since the polyisocyanate mixtures of the present invention primarily contain allophanate structures as structural elements, they may also be referred to interchangeably as allophanate polyisocyanates of the present invention or PDI-based allophanate polyisocyanates of the present invention. The polyisocyanate mixtures of the present invention represent valuable starting materials for the production of polyurethane plastics by the isocyanate polyaddition process. Therefore, the present invention further provides the use of the polyisocyanate mixtures of the present invention as starting components in the production of polyurethane plastics.

[0072] The polyisocyanate mixtures according to the invention are highly suitable as curing agents for two-component polyurethane coatings in which conventional polyether polyols, polyester polyols, polycarbonate polyols and / or polyacrylate polyols are present as hydroxy-functional components as coreactants with the polyisocyanates. Preferred hydroxy-functional components are polyacrylate polyols, i.e., polymers or copolymers of alkyl (meth)acrylates and, optionally, styrene or other copolymerizable olefinically unsaturated monomers.

[0073] They may be used both as the sole crosslinker component or, due to their low viscosity, as reactive diluents for higher-viscosity polyisocyanates, particularly those with uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret, and / or oxadiazinetrione structures having aliphatically, cycloaliphatically, araliphatically, and / or aromatically bound isocyanate groups, preferably those based on PDI. The present invention further provides the use of the polyisocyanate mixtures according to the invention for diluting relatively high-viscosity polyisocyanates, preferably those based on 1,5-diisocyanatopentane, while simultaneously maintaining reactivity.

[0074] The present invention also provides the use of the polyisocyanate mixtures of the present invention for blending with polyisocyanates having a uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret, and / or oxadiazinetrione structure with aliphatically, cycloaliphatically, araliphatically, and / or aromatically bound isocyanate groups, preferably based on 1,5-diisocyanatopentane. This has the advantage of further improving processability while simultaneously enabling the replacement of fossil raw materials. The present invention also provides blends of the polyisocyanate mixtures of the present invention with polyisocyanates having a uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret, and / or oxadiazinetrione structure with aliphatically, cycloaliphatically, araliphatically, and / or aromatically bound isocyanate groups, preferably based on 1,5-diisocyanatopentane.

[0075] Due to their low viscosity, the allophanate polyisocyanates / polyisocyanate mixtures of the present invention can be used without solvent, but if necessary, they can be diluted without clouding with conventional solvents, such as those mentioned above that are inert to the isocyanates optionally used in the process of the present invention. Generally, coating compositions formulated using the polyisocyanates of the present invention, which may incorporate conventional coating compositions, optionally containing auxiliaries and additives such as flow control aids, color pigments, fillers, or matting agents, have good coating properties even when dried at room temperature. However, they can, of course, also be dried under forced conditions at elevated temperatures or by baking at temperatures up to 260°C.

[0076] To control the cure rate, suitable catalysts, such as those customary in isocyanate chemistry, such as tertiary amines, for example triethylamine, pyridine, methylpyridine, benzyldimethylamine, N,N-endoethylenepiperazine, N-methylpiperidine, pentamethyldiethylenetriamine, N,N-dimethylaminocyclohexane, N,N'-dimethylpiperazine, or metal salts, such as iron(III) chloride, zinc chloride, zinc 2-ethylcaproate, tin(II) octoate, tin(II) ethylcaproate, dibutyltin(IV) dilaurate, bismuth(III) 2-ethylhexanoate, bismuth(III) octoate or molybdenum glycolate, may be used concomitantly during the formulation of the coating composition.

[0077] The allophanate polyisocyanates according to the invention are also suitable as crosslinker components for binders or binder components that are soluble or dispersible in water and have groups reactive with isocyanate groups, especially alcoholic hydroxyl groups, in the preparation of aqueous two-component polyurethane systems. Due to their low viscosity, they can be used as is, i.e., in hydrophobic form, or in a form that has been hydrophilically modified by known methods, for example, as disclosed in EP 0 540 985, EP 0 959 087, or EP 1 287 052.

[0078] The allophanate polyisocyanates according to the invention may also be combined with polyamines, such as the polyaspartic acid derivatives known from EP 0 403 921, which are produced by reacting diamines with fumaric or maleic esters, or polyamines in which the amino groups are in blocked form, such as polyketimines, polyaldimines or oxazolanes. The effect of moisture on these blocked amino groups is to convert them into free amino groups and, in the case of oxazolanes, also into free hydroxyl groups which react with the isocyanate groups of the polyisocyanates according to the invention during crosslinking.

[0079] The allophanate polyisocyanates according to the invention may also be combined with a compound containing at least one thiol group.

[0080] These include, for example, polythiols known from EP-A-3 872 108, such as simple alkanethiols, thioether group containing polythiols, polyether thiols, polyester thiols, aromatic thio compounds and / or mercaptoalcohols.

[0081] In a preferred embodiment, the isocyanate groups of the allophanate polyisocyanates according to the invention may be partially or completely reacted with at least one blocking agent.

[0082] These blocking agents are in particular blocking agents known per se from polyurethane chemistry, such as diethyl malonate, ethyl acetoacetate, activated cyclic ketones such as cyclopentanone-2-carboxymethyl ester and -carboxyethyl ester, acetone oxime, butanone oxime, ε-caprolactam, 3,5-dimethylpyrazole, 1,2,4-triazole, dimethyl-1,2,4-triazole, imidazole, diisopropylamine, benzyl-tert-butylamine, or any desired mixtures of these blocking agents.

[0083] In blocked form, the polyisocyanates according to the invention can also be used in combination with the aforementioned coating binders or coating binder components in the context of one-component PUR baking systems.

[0084] In all coating combinations, the polyisocyanates according to the invention and the co-reactants are present in amounts such that there are 0.5 to 3, preferably 0.6 to 2.0, and particularly preferably 0.8 to 1.6, optionally blocked isocyanate-reactive groups per each optionally blocked isocyanate group. However, the allophanate polyisocyanates according to the invention may also be mixed in small amounts with non-functional coating binders to achieve very specific properties, for example as an additive to improve adhesion.

[0085] Substrates contemplated for coatings formulated using the polyisocyanates according to the invention include any desired substrate, such as metal, wood, glass, stone, ceramic materials, concrete, rigid and flexible plastics, textiles, leather, and paper, which may be provided with a conventional primer prior to coating.

[0086] The present invention therefore further provides a coating composition comprising an allophanate polyisocyanate according to the invention and a substrate at least partially coated with a polyurethane, polyurea and / or polythiourethane according to the invention and / or at least one polyisocyanate mixture according to the invention and / or at least one coating composition according to the invention.

[0087] The coating composition according to the invention may be in the form of a two-component system, for example comprising a crosslinker component containing at least one polyisocyanate mixture according to the invention and a binder component containing at least one coating binder or coating binder component having groups reactive towards isocyanate groups, or in the form of a one-component system containing at least one polyisocyanate mixture according to the invention present in blocked form. Such systems likewise form part of the subject matter of the present invention.

[0088] In addition to their preferred use as crosslinker components for solvent-free, solvent-containing or aqueous 2K PUR coatings, the polyisocyanates according to the invention are also highly suitable as crosslinkers for solvent-free or solvent-containing adhesive binders or aqueous dispersion adhesives, or as synthesis components for the production of otherwise light-resistant compression moldings or foamed polyurethane moldings.

[0089] The present invention therefore further provides polyurethanes, polyureas and / or polythiourethanes obtained or produced by reacting at least one polyisocyanate mixture according to the invention with at least one hydroxy-, amino- and / or thio-functional component.

[0090] The features specified as being preferred for the process according to the invention or the polyisocyanate mixture according to the invention are also preferred for the further subject matter of the invention.

[0091] The following examples serve to illustrate the invention but should not be understood as imposing any limitation on the scope of protection.

[0092] [Example] Unless otherwise stated, all percentages are by weight.

[0093] The NCO content was determined by titration according to DIN EN ISO11909:2007-05.

[0094] All viscosity measurements were taken at 250 s -1 The rheometry was carried out at a shear rate of 100 rpm using a Physica MCR 51 rheometer from Anton Paar Germany GmbH (DE) in accordance with DIN EN ISO 3219:1994-10.

[0095] The residual monomer content was determined according to DIN EN ISO10283:2007-11 by gas chromatography with an internal standard.

[0096] The content of sodium and potassium cations was determined by inductively coupled plasma atomic emission spectrometry (ICP-OES) according to DIN EN ISO 11885:2009-09 after microwave digestion. The limit of detection by this method is below 1 ppm.

[0097] The platinum-cobalt color index was measured spectrophotometrically according to DIN EN ISO6271-2:2005-03 using a Lico 400 spectrophotometer from Lange, Germany.

[0098] The content (mol %) of allophanate, urethane and optionally isocyanurate and / or uretdione structures present in the polyisocyanates according to the invention is determined by proton decoupling. 13 The values ​​were calculated from the integrals of the C-NMR spectra (recorded on a Bruker DPX-400 instrument) and are based on the summation of the allophanate, urethane, isocyanurate, and / or uretdione structures present, respectively. For PDI and HDI polyisocyanates dissolved in CDCl, the individual structural elements have the following chemical shifts (ppm): allophanate: 155.7 and 153.8; urethane: 156.3; isocyanurate: 148.4; uretdione: 157.1.

[0099] [Example 1] (Example of the present invention) Under dry nitrogen, 1234 g (8.0 mol) of pentamethylene diisocyanate (PDI) was mixed with 341 g (1.0 mol) of ethoxylated lauryl alcohol (OH number: 164.4 mg KOH / g, Na content: 34 mg / kg, K content: less than 1 mg / kg) for an average of four times at 80°C. The mixture was stirred for 3 hours until an NCO content of 40.0%, corresponding to complete urethanization, was achieved. The reaction mixture was then heated to 95°C, and 0.16 g of zinc(II) 2-ethyl-1-hexanoate was added as an allophanatization catalyst. An exothermic reaction began, raising the temperature of the mixture to 106°C. The exotherm subsided after approximately 30 minutes of reaction time. The NCO content of the reaction mixture was 37.1%. The catalyst was deactivated by adding 0.16 g of orthophosphoric acid and the unconverted monomeric PDI was separated in a thin-film evaporator at a temperature of 130° C. and a pressure of 0.1 mbar, giving 679 g of a virtually colorless, transparent allophanate polyisocyanate having the following characteristics:

[0100] NCO content: 12.6% Monomer PDI: 0.04% Viscosity (23℃): 175mPas Number of colors (APHA): 15 Hazen Composition: Allophanate: 82.6 mol% Urethane: 9.4 mol% Isocyanurate: 7.6 mol% Uretdione: 0.4 mol%

[0101] [Example 2] (Example of the present invention) 1234 g (8.0 mol) of PDI was initially charged under dry nitrogen with stirring at a temperature of 95°C and mixed with 0.16 g of zinc(II) 2-ethyl-1-hexanoate as catalyst. Over a period of approximately 45 minutes, 341 g (1.0 mol) of lauryl alcohol, ethoxylated an average of four times as used in Example 1, was added dropwise, initiating an exothermic reaction that raised the temperature of the mixture to 100°C. The reaction mixture was further stirred at 100°C until the NCO content had dropped to 37.2% after approximately 1 hour. The catalyst was deactivated by adding 0.16 g of orthophosphoric acid, and the unconverted monomeric PDI was separated in a thin-film evaporator at a temperature of 130°C and a pressure of 0.1 mbar. This resulted in 666 g of a substantially colorless, transparent allophanate polyisocyanate mixture having the following characteristics and composition:

[0102] NCO content: 12.4% Monomer PDI: 0.03% Viscosity (23℃): 164mPas Number of colors (APHA): 21 Hazen Composition: Allophanate: 83.0 mol% Urethane: 9.1 mol% Isocyanurate: 7.5 mol% Uretdione: 0.4 mol%

[0103] [Example 3] (Comparative Example) 1344 g (8.0 mol) of hexamethylene diisocyanate (HDI) was mixed with 341 g (1.0 mol) of lauryl alcohol (used in Example 1, ethoxylated an average of four times) at 80°C under dry nitrogen and stirred for 3 hours until an NCO content of 37.4%, corresponding to complete urethanization, was achieved. The reaction mixture was then heated to 95°C, and 0.17 g of zinc(II) 2-ethyl-1-hexanoate was added as an allophanatization catalyst. An exothermic reaction began, causing the temperature of the mixture to rise to 104°C. The exotherm subsided again after about 30 minutes of reaction time. The NCO content of the reaction mixture was 34.7%. The catalyst was deactivated by adding 0.17 g of orthophosphoric acid, and the unconverted monomeric HDI was separated in a thin-film evaporator at 130°C and 0.1 mbar pressure. This gave 715 g of a substantially colorless allophanate polyisocyanate having the following characteristics:

[0104] NCO content: 12.3% Monomer HDI: 0.01% Viscosity (23℃): 148mPas Number of colors (APHA): 25 Hazen Composition: Allophanate: 83.3 mol% Urethane: 9.5 mol% Isocyanurate: 6.6 mol% Uretdione: 0.6 mol% The PDI allophanate polyisocyanates of the present invention and the HDI-based comparative polyisocyanates from Examples 1 and 2 were stored at room temperature for four weeks. The PDI polyisocyanates remained completely clear, while the HDI polyisocyanates showed visible turbidity after only one day. After four weeks, a distinct precipitate formed. The comparison demonstrates the clearly improved crystallization stability of the PDI products compared to the equivalently synthesized HDI derivatives.

[0105] [Example 4] (Example of the present invention) 987 g (6.4 mol) of PDI together with 267 g (1.6 mol) of HDI were initially charged under dry nitrogen with stirring at a temperature of 80°C and mixed with 0.16 g of zinc(II) 2-ethyl-1-hexanoate as catalyst. Over a period of approximately 30 minutes, 341 g (1.0 mol) of lauryl alcohol, ethoxylated an average of four times as used in Example 1, was added dropwise, initiating an exothermic reaction that raised the temperature of the mixture to 102°C. The reaction mixture was further stirred at 100°C until the NCO content had dropped to 36.1% after approximately 1.5 hours. The catalyst was deactivated by adding 0.16 g of orthophosphoric acid, and the unconverted monomeric diisocyanates were separated in a thin-film evaporator at a temperature of 130°C and a pressure of 0.1 mbar. This resulted in 677 g of a substantially colorless, transparent allophanate polyisocyanate mixture having the following characteristics and composition:

[0106] NCO content: 13.5% Monomer PDI: 0.01% Monomer HDI: 0.01% Viscosity (23℃): 245mPas Number of colors (APHA): 30 Hazen Composition: Allophanate: 72.7 mol% Urethane: 6.1 mol% Isocyanurate: 20.7 mol% Uretdione: 0.5 mol%

[0107] [Example 5] (Example of the present invention) 1234 g (8.0 mol) of PDI was initially charged under dry nitrogen with stirring at a temperature of 95°C and mixed with 0.32 g of catalyst zirconium(IV) 2-ethyl-1-hexanoate. Over a period of approximately 45 minutes, 341 g (1.0 mol) of lauryl alcohol, ethoxylated an average of four times as used in Example 1, was added dropwise, initiating an exothermic reaction that raised the temperature of the mixture to 107°C. The reaction mixture was further stirred at 100°C until the NCO content had dropped to 37.1% after approximately 1.5 hours. The catalyst was deactivated by adding 0.32 g of orthophosphoric acid, and the unconverted monomeric PDI was separated in a thin-film evaporator at a temperature of 130°C and a pressure of 0.1 mbar. This resulted in 658 g of a substantially colorless, transparent allophanate polyisocyanate mixture having the following characteristics and composition:

[0108] NCO content: 12.2% Monomer PDI: 0.03% Viscosity (23℃): 150mPas Number of colors (APHA): 15 Hazen Composition: Allophanate: 88.1 mol% Urethane: 6.6 mol% Isocyanurate: 4.8 mol% Uretdione: 0.5 mol%

[0109] [Examples 6 to 13] (Examples of the present invention) According to the method described in Example 2, PDI was reacted with lauryl alcohol ethoxylates of different ethoxylation degrees at different NCO:OH equivalent ratios under zinc octoate catalysis, and the resulting mixtures were worked up by thin-film distillation. The following table shows the compositions and characteristics of the reaction batches and the allophanate polyisocyanates obtained after thin-film distillation.

[0110] [Table 1]

Claims

1. General formula (I) 【Chemistry 1】 (In the formula, R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having (6 to 22)-p carbon atoms, which may in each case be substituted; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; n is an integer from 1 to 12, m is an integer from 1 to 10, and p is 0 or 1. A polyisocyanate mixture containing at least one polyisocyanate of the formula:

2. 2. The polyisocyanate mixture according to claim 1, having an NCO content of 6.0 to 18.0% by weight, preferably 8.0 to 16.0% by weight, particularly preferably 10.0 to 15.0% by weight, based on the total weight of the polyisocyanate mixture, and / or a residual monomer content, determined by gas chromatography using an internal standard in accordance with DIN EN ISO 10283:2007-11, of less than 0.14% by weight, preferably less than 0.12% by weight, particularly preferably less than 0.10% by weight, based on the total weight of the polyisocyanate mixture.

3. Viscosity at 23°C of less than 500 mPas, preferably less than 400 mPas, particularly preferably less than 300 mPas －１ 3. The polyisocyanate mixture according to claim 1, having a viscosity measured in accordance with DIN EN ISO 3219:1994-10 at a shear rate of 0.05 to 0.

15.

4. 3. A process for producing the polyisocyanate mixture of claim 1 or 2, comprising: A) a diisocyanate component containing at least 1,5-diisocyanatopentane, B) General formula (II) 【Chemistry 2】 (In the formula, R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having (6 to 22)-p carbon atoms, which may in each case be substituted; R' and R" independently represent hydrogen or an aliphatic group having 1 to 10 carbon atoms, and at least one of the groups R' and R" represents hydrogen; n is an integer from 1 to 12, m is an integer from 1 to 10, and p represents 0 or 1. with at least one alcohol of

5. 5. The process according to claim 4, characterized in that 1,5-pentamethylene diisocyanate and optionally further diisocyanates having aliphatically, cycloaliphatically, araliphatically and / or aromatically bound isocyanate groups are used as diisocyanate component A) in an amount of up to 40% by weight, based on diisocyanate component A).

6. General formula (III) 【Transformation 3】 (In the formula, R １ represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having in each case 6 to 22, preferably 8 to 20, particularly preferably 10 to 18, very particularly preferably 12 to 14 carbon atoms, which may be substituted. Alkoxylation products of fatty alcohols of formula (I), and / or general formula (IV) 【Chemistry 4】 (In the formula, R ２ represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated alicyclic radical having in each case 5 to 21, preferably 7 to 19, particularly preferably 9 to 17, very particularly preferably 11 to 13 carbon atoms, which may be substituted.

5. The process according to claim 4, characterized in that an alkoxylation product of a fatty acid of the formula:

7. 5. The process according to claim 4, characterized in that the alcohol component B) used is selected from the alkoxylation products of 1-decanol, 1-dodecanol, 1-tetradecanol, 1-octadecanol, decanoic acid, dodecanoic acid, tetradecanoic acid and / or hexadecanoic acid.

8. 5. The process according to claim 4, characterized in that the alcohol component B) is selected from alkoxylation products having on average 1 to 10, preferably 1 to 7, particularly preferably 2 to 5, very particularly preferably 2 to 4 alkylene oxide units, the alkylene oxide units preferably comprising or consisting of ethylene oxide and / or propylene oxide units.

9. 5. The process of claim 4, comprising reacting the diisocyanate component A) containing at least 1,5-diisocyanatopentane with at least one alcohol component B) at a temperature of from 40° C. to 200° C., preferably from 60° C. to 180° C., and / or while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of from 4:1 to 50:1, preferably from 5:1 to 30:1, to obtain an allophanate polyisocyanate.

10. 5. The process according to claim 4, characterized in that it comprises reacting the diisocyanate component A) containing at least 1,5-diisocyanatopentane with at least one alcohol component B) in the presence of at least one allophanatization catalyst, preferably at least zinc(II) n-octoate, zinc(II) 2-ethyl-1-hexanoate and / or zinc(II) stearate, zirconium(IV) n-octoate, zirconium(IV) 2-ethyl-1-hexanoate and / or zirconium(IV) neodecanoate.

11. 3. Use of the polyisocyanate mixtures according to claim 1 or 2 as starting components in the production of polyurethane plastics.

12. 3. Use of the polyisocyanate mixtures according to claim 1 or 2 for blending with polyisocyanates having uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret and / or oxadiazinetrione structures with aliphatically, cycloaliphatically, araliphatically and / or aromatically bound isocyanate groups, preferably those based on 1,5-diisocyanatopentane.

13. 3. Use of the polyisocyanate mixtures according to claim 1 or 2 for diluting polyisocyanates with higher viscosities, preferably polyisocyanates with higher viscosities based on 1,5-diisocyanatopentane, while simultaneously maintaining reactivity.

14. 10. Polyurethanes, polyureas and / or polythiourethanes obtained or produced by reacting at least one polyisocyanate mixture according to claim 1 with at least one hydroxy-, amino- and / or thio-functional component.

15. 4. A coating composition comprising at least one polyisocyanate mixture according to claim 1, wherein the at least one polyisocyanate mixture is present in a mixture with polyisocyanates having uretdione, isocyanurate, iminooxadiazinedione, urethane, allophanate, biuret and / or oxadiazinetrione structures with aliphatically, cycloaliphatically, araliphatically and / or aromatically bound isocyanate groups, preferably those based on 1,5-diisocyanatopentane.

16. 16. A substrate at least partially coated with at least one polyisocyanate mixture according to claim 1 or 2 and / or at least one polyurethane, polyurea and / or polythiourethane according to claim 14 and / or at least one coating composition according to claim 15.

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