EP0000723B1 - Polyhydroxy compounds containing urethane-aryl-sulfonic acid-hydroxyalkyl ester groups, process for their preparation and their use as reaction components for the preparation of polyurethane resins - Google Patents

Description

• di- und höherfunktionelle Alkohole, wie z.B. Äthylenglykol, Diäthylenglykol, Hexandiol, Glycerin, Trimethylolpropan sowie höhermolekulare Polyäther, Polythioäther, Polyester, Polyacetale. Die höhermolekularen Polyhydroxyverbindungen werden in bekannter Weise aus niedermolekulares Bausteinen hergestellt.

For the production of polyurethanes, it is known to react polyisocyanates with compounds which contain two to six OH groups and have a molecular weight between 62 and about 10,000. These polyhydroxy compounds include, for example:

• di- and higher functional alcohols, such as ethylene glycol, diethylene glycol, hexanediol, glycerin, trimethylolpropane as well as higher molecular weight polyethers, polythioethers, polyesters, polyacetals. The higher molecular weight polyhydroxy compounds are produced in a known manner from low molecular weight building blocks.

In these polyhydroxy compounds, the various OH functions are generally equivalent in terms of reactivity and distance from any branching center that may be present. Exceptions are low molecular weight alcohols which have primary and secondary hydroxyl groups, such as glycerin. In the case of higher molecular weight polyethers and polyesters, both primary and secondary OH groups are also frequently present, but their distribution is statistical, so that it is not possible to build up polymers with a defined structure on account of this difference in reactivity. The chain length distributions in branched polyethers and polyesters also obey the laws of statistics.

It is also known that the above. Extend polyhydroxy compounds by a molar amount of a polysiocyanate to OH prepolymers. In the case of trifunctional isocyanates, branching does occur, but the reactivity of the OH groups and the chain length distribution are again statistical.

A separate production of OH prepolymers for the subsequent production of polyurethanes is usually not useful, since the same polyurethane structures are produced by production using the one-shot process or using NCO prepolymers.

For the production of polyurethanes and in particular for the production of spatially crosslinked polyurethanes, polyhydroxy compounds are now desired which have OH groups of different reactivity and chain branches of different lengths in a defined manner. It would be advantageous, for example, to have trifunctional polyhydroxy compounds which would have 2 OH groups of high reactivity at the ends of the main chain and an OH function of reduced reactivity on the shortest possible side chain, because of such a structure a polymer with particularly favorable mechanical properties is to be expected. It is also desirable to be able to use polyhydroxy compounds which provide polyurethanes with improved fire behavior. Finally, OH prepolymers are desired which do not produce toxicologically questionable aromatic diamines during hydrolytic degradation.

Reaction of the reaction products with oxiranes or oxetanes novel polyhydroxy compounds of higher functionality can be obtained. The OH group resulting from the reaction of the sulfonic acid group with the cyclic ether is located on a short side chain.

It has also been found that novel polyhydroxy compounds with modified functionality and / or reactivity are obtained by reacting conventional polyhydroxy compounds with equivalent amounts of monoisocyanate mono- or polysulfonic acids and then reacting the reaction products with oxiranes or oxetanes.

The present invention thus relates to at least two hydroxyl groups and compounds having at least one sulfonic acid ester group and having an average molecular weight of 300 to 12,000, in which at least one hydroxyl group is present in the form of a urethane-aryl-sulfonic acid hydroxyalkyl ester.

According to the invention, preference is given to compounds which have an average molecular weight of 300 to 12000, characterized by at least one OH-functional long chain which contains 6 to 400 chain links, preferably 20 to 300 chain links, and at least one linked to a branching site via a sulfonic acid ester residue OH-functional short chain, which contains 2 to 3 chain links, and at least one, at least trifunctional aryl radical as a branching point.

in der

• R₁ einen 2- bis 6-wertigen Rest eines Polyols, z.B. eines Polyesters, Polyäthers, Polythioäthers oder Polyesteramids und
• Ar einen mehrwertigen Rest eines aromatischen Isocyanats darstellt,

insbesondere mindestens eine Struktureinheit der allgemeinen Formel

in der

• R, und Ar die schon genannten Bedeutungen haben und
• R₂, R₄ H, C,―C₈-Alkyl, C₆―C₁₄-Aryl), Rest eines Epoxids, vorzugsweise ―CH₂―0―R₈, ―CH₂―X, CH₂―0―CO―R_g, weitere Epoxidgruppen enthaltender aliphatischer C₁―C₈-Alkylrest,
• R₃, R₅, R₆, R₇, H, C₁―C₈-Alkyl, C₆―H₁₄-Aryl) und
• R₈, R₉ C₁―C₈-Alkyl, C₆―H₁₄-Aryl und X OH, Cl, Br, CN

bedeuten.The compounds according to the invention preferably contain at least one structural unit of the general formula:

in the

• R _{1 is} a 2- to 6-valent radical of a polyol, for example a polyester, polyether, polythioether or polyester amide and
• Ar represents a polyvalent radical of an aromatic isocyanate,

in particular at least one structural unit of the general formula

in the

• R, and Ar have the meanings already mentioned and
• R ₂ , R ₄ H, C, ―C ₈ alkyl, C ₆ ―C ₁₄ aryl), residue of an epoxide, preferably ―CH ₂ ―0 ― R ₈ , ―CH ₂ ―X, CH ₂ ―0 ― CO ―R _g , aliphatic C ₁ ―C ₈ alkyl radical containing further epoxide groups,
• R ₃ , R ₅ , R ₆ , R ₇ , H, C ₁ ―C ₈ alkyl, C ₆ ―H ₁₄ aryl) and
• R ₈ , R ₉ C ₁ ―C ₈ alkyl, C ₆ ―H ₁₄ aryl and X OH, Cl, Br, CN

mean.

insbesondere

und

insbesondere

in denen

• R_1' R₂, R₃, R₄, R₅, R₆, R₇ und Ar die schon genannte Bedeutung aufweisen.

According to the invention, compounds of the following general formulas are preferred:

in particular

and

in particular

in which

• R _{1 '} R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ and Ar have the meaning already mentioned.

The present invention also relates to a process for the preparation of compounds having at least two hydroxyl groups and at least one sulfonic acid ester group, of average molecular weight 300 to 12,000, in which at least one hydroxyl group is in the form of a urethane aryl sulfonic acid hydroxyalkyl ester, characterized in that at least two hydroxyl-containing compounds with a molecular weight of 62 to 10,000 at 0―190 ° C with isocyanatosulfonic acid and then with oxiranes and / or oxetanes, the equivalent ratio of the total amount of isocyanate groups (including any dimerized isocyanate groups) to sulfonic acid groups 0 , 5 to 50, the equivalent ratio of the sum of the hydroxyl groups of the at least two hydroxyl group-containing compounds and the sulfonic acid groups to NCO groups 1.5 to 30 and the equivalent ratio of the oxirane or oxetane groups to sulfonic acid groups is 0.2 to 5.

The present invention finally also relates to the use of the compounds according to the invention as a reaction component for polyisocyanates for the production of polyaddition products or polycondensation products.

• 1. Sie besitzen stark polaren Charakter, außerordentlich niedrigen Dampfdruck und sind hervorragend verträglich mit einer Vielzahl polarer und apolarer Medien und Reaktionspartnern.
• 2. In Abhängigkeit von der chemischen Konstitution der eingesetzten Oxirans bzw. Oxetans läßt sich die Reaktivität der über eine kurze Seitenkette an die Verzweigungsstelle gebundenen OH-Gruppe wunschgemäß steuern. Die Reaktivität dieser OH-Gruppe kann höher, nahezu gleich oder auch geringer sein als die der über die Polyhvdroxyverbindung eingeführten OH-Gruppe.
• 3. Die Funktionalität der als Ausgangsmaterial eingesetzten Polyhydroxyverbindungen läßt sich in Abhängigkeit von der Menge an eingesetzter Isocyanatosulfonsäure wunschgemäß erhöhen, z.B. von 2 auf 2,1 oder z.B. auch auf 3 oder 4.
• 4. In Abhängigkeit von Natur und Menge des verwendeten Oxirans oder Oxetans läßt sich die Hydrophilie und die Acidität der Produkte in weiten Grenzen steuern. Bei vollständiger Umsetzung der Sulfonsäure-Gruppen mit Oxiranen oder Oxetanen erhält man weitgehend hydrophobe Polyhydroxyverbindungen.
• 5. Der hydrolytische Abbau der Produkte führt zu toxikologisch unbedenklichen Polyaminosulfonsäuren.
• 6. Die Verwendung der erfindungsgemäßen Verbindungen beispielsweise bei der Herstellung von Polyurethanen führt zu Polymeren mit verbessertem Brandverhalten.

The new compounds according to the invention have a number of advantageous properties compared to the polyhydroxy compounds known hitherto:

• 1. They have a strongly polar character, extremely low vapor pressure and are extremely compatible with a large number of polar and apolar media and reaction partners.
• 2. Depending on the chemical constitution of the oxirane or oxetane used, the reactivity of the OH group bound to the branching point via a short side chain can be controlled as desired. The reactivity of this OH group can be higher, almost the same or also lower than that of the OH group introduced via the polyhydric compound.
• 3. Depending on the amount of isocyanatosulfonic acid used, the functionality of the polyhydroxy compounds used as the starting material can be increased as desired, for example from 2 to 2.1 or, for example, to 3 or 4.
• 4. Depending on the nature and amount of the oxirane or oxetane used, the hydrophilicity and acidity of the products can be controlled within wide limits. When the sulfonic acid groups are fully reacted with oxiranes or oxetanes, largely hydrophobic polyhydroxy compounds are obtained.
• 5. The hydrolytic degradation of the products leads to toxicologically harmless polyaminosulfonic acids.
• 6. The use of the compounds according to the invention, for example in the production of polyurethanes, leads to polymers with improved fire behavior.

The products obtained according to the invention or the chain segments obtained from these products in the construction of polyurethanes are not readily available in any other way, since the direct reaction of isocyanatoarylsulfonic acids or NCO prepolymers prepared therefrom with oxiranes or oxetanes provides other products or chain segments of different construction . The compounds according to the invention preferably contain at least one segment which is a 2- to 6-valent radical of a polyether, polythioether, polyester or polyester amide.

When carrying out the process according to the invention, a part of the OH groups of the polyhydroxy compounds used as starting material and the NCO groups and any uretdione groups of isocyanatoarylsulfonic acid which may be present are normally added in a first reaction step, with the formation of higher molecular weight new polyhydroxy compounds which initially contain urethane -Groups and contain one or more free sulfonic acid groups. The sulfonic acid group is then esterified by the added oxirane or oxetane, whereby hydroxyalkyl sulfonic acid ester groups are formed.

In the process according to the invention, all compounds usually used in polyurethane chemistry with at least two hydroxyl groups and a molecular weight of 62 to 10,000 can be used as the starting material. Examples of these are low molecular weight glycols, polyesters, polyethers, polyesteramides, OH groups-containing oligomers and polymers, for example based on butadiene, and polyethers grafted with vinyl monomers or polyhydroxyl compounds which contain other polymers, such as e.g. Contain dispersed polyureas, urea resins, polyhydrazodicarbonamides or vinyl polymers. Suitable compounds of this type containing hydroxyl groups are described, for example, in German Patent Specifications 1 152 536, 1 168 075 and 1 260 142, German Offenlegungsschriften 2,324,134, 2,423,984, 2,512,385, 2,513,815, 2,550,796, 2,550,797 , 2,550,833, 2,550,662 and 2,550,860, and U.S. Patents 3,383,351, 3,304,273, 3,523,093, 3,110,695, and 3,869,413.

• 4,4' - Stilbendiisocyanat, 4,4' - Dibenzyldiisocyanat, 3,3' - bzw. 2,2' - dimethyl - 4,4' - diisocyanato - diphenylmethan, 2,3,2',5' - Tetramethyl - 4,4' - diisocyanato - diphenylmethan, 3,3' - Dimethoxy - 4,4' - diisocyanato - diphenylmethan, 3,3' - Dichlor - 4,4' - diisocyanato - diphenylmethan, 4,4' - Diisocyanato - diphenylcyclohexylmethan, 4,4' - Diisocyanato - benzophenon, 4,4' - Diisocyanato diphenylsulfon, 4,4' Diisocyanato-diphenyläther, 4,4' - Diisocyanato - 3,3' - dibrom - diphenylmethan, 4,4'-Diisocyanato - 3,3'-diäthyl - diphenylmethan, 4,4' - Diisocyanato - = diphenyl - äthylen - (1,2), 4,4' - Diisocyanato - diphenyl - sulfid, 1,3- und 1,4 - Phenylendiisocyanat, 2,4- -und 2,6 - Toluylendiisocyanat sowie bliebige Gemische dieser Isomeren, Diphenylmethan - 2,4' - und/oder -4,4' - diisocyanat, Naphthylen-1,5 - diisocyanat, Triphenylmethan - 4,4' 4" - triisocyanat, Polyphenyl - polymethylen - polyisocyanate, wie sie durch Anilin - Formaldehyd - Kondensation und anschließende Phosgenierung erhalten und z.B. in den britischen Patentschriften 874 430 und 848 671 beschrieben werden, Carbodiimidgruppen aufweisende Polyisocyanate, wie sie in der deutschen Patentschrift 1 092 007 beschrieben werden, Diisocyanate, wie sie in der amerikanischen Patentschrift 3 492 330 beschrieben werden, Allophanatgruppen aufweisende Polyisocyanate, wie sie z.B. in der britischen Patentschrift 994 890, der belgischen Patentschrift 761 626 und der veröffentlichten holländischen Patentanmeldung 7 102 524 beschrieben werden, Isocyanuratgruppen aufweisende Polyisocyanate, wie sie z.B. in der deutschen Patentschriften 1 022 789, 1 222 067 und 1 027 394, sowie in den deutschen Offenlegungsschriften 1 929 034 und 2 004 048 beschriben werden, acylierte Harnstoffgruppen aufweisende Polyisocyanate gemäß der deutschen Patentschrift 1 230 778, Biuretgruppen aufweisende Polyisocyanate, wie sie z.B. in der deutschen Patentschrift 1 101 394, in der britischen Patentschrift 889050 und in der französischen Patentschrift 7 017 514 beschrieben werden. Es ist auch möglich, die bei der technischen Isocyanatherstellung anfallenden Isocyanat- gruppen aufweisenden Destillationsrückstände, gegebenenfalls gelöst in einem oder mehreren der vorgenannten Polyisocyanate, einzusetzen. Ferner ist es möglich, beliebige Mischungen der vorgenannten Polyisocyanate zu verwenden.

In the process according to the invention, the sulfonation products of all known aromatic polyisocyanates can be used as isocyanatoarylsulfonic acids. Examples of aromatic polyisocyanates of this type which can be used in the form of their sulfonation products in the process according to the invention are:

• 4,4 '- stilbene diisocyanate, 4,4' - dibenzyl diisocyanate, 3,3 '- or 2,2' - dimethyl - 4,4 '- diisocyanato - diphenylmethane, 2,3,2', 5 '- tetramethyl - 4 , 4 '- diisocyanato - diphenylmethane, 3,3' - dimethoxy - 4,4 '- diisocyanato - diphenylmethane, 3,3' - dichloro - 4,4 '- diisocyanato - diphenylmethane, 4,4' - diisocyanato - diphenylcyclohexylmethane, 4 , 4 '- diisocyanato - benzophenone, 4,4' - diisocyanato diphenylsulfone, 4,4 'diisocyanato diphenyl ether, 4,4' - diisocyanato - 3,3 '- dibromo - diphenylmethane, 4,4'-diisocyanato - 3,3 '-Diethyl-diphenylmethane, 4,4' - diisocyanato - = diphenyl - ethylene - (1,2), 4,4 '- diisocyan ato - diphenyl sulfide, 1,3 - and 1,4 - phenylene diisocyanate, 2,4 - and 2,6 - tolylene diisocyanate as well as residual mixtures of these isomers, diphenyl methane - 2,4 '- and / or -4,4' - diisocyanate, naphthylene-1,5-diisocyanate, triphenylmethane-4,4'4 "-triisocyanate, polyphenyl-polymethylene-polyisocyanates, as obtained by aniline-formaldehyde condensation and subsequent phosgenation and, for example, in British Patents 874,430 and 848,671 are described, polyisocyanates containing carbodiimide groups, as described in German Patent 1,092,007, diisocyanates, as described in American Patent 3,492,330, polyisocyanates containing allophanate groups, as described, for example, in British Patent 994 890, the Belgian patent 761 626 and the published Dutch patent application 7 102 524, polyisocyanates containing isocyanurate groups, as described, for example, in German patent specifications 1,022 789, 1 222 067 and 1 027 394, as well as in German Offenlegungsschriften 1 929 034 and 2 004 048, polyisocyanates containing acylated urea groups according to German Patent 1,230,778, polyisocyanates containing biuret groups, as described, for example, in German Patent 1 101 394, British Patent 889050 and French Patent 7 017 514. It is also possible to use the distillation residues containing isocyanate groups obtained in the technical production of isocyanates, optionally dissolved in one or more of the aforementioned polyisocyanates. It is also possible to use any mixtures of the aforementioned polyisocyanates.

Phosgenation products of condensates of aniline and aldehydes or ketones, such as e.g. Acetaldehyde, propionaldehyde, butyraldehyde, acetone, methyl ethyl ketone. Also suitable are the phosgenation products of condensates of anilines substituted on the core alkyl, in particular toluidines with aldehydes or ketones, such as, for example, formaldehyde, acetaldehyde, butyraldehyde, acetone, methyl ethyl ketone.

Also suitable are reaction products of the aromatic polyisocyanate mixtures mentioned with 0.2-50 mol% of polyols, provided that the viscosity of the reaction products thus obtained does not exceed 50,000 cP at 25 ° C. and the NCO content of the reaction products is at least 6% by weight. % is. Suitable polyols for modifying the starting materials are, in particular, the polyether and / or polyester polyols of the molecular weight range 200 to 6000, preferably 300 to 4000, which are known in polyurethane chemistry, and low molecular weight polyols of the molecular weight range 62 to 200. Examples of such low molecular weight polyols are ethylene glycol, propylene glycol, Glycerin, trimethylolpropane, 1,4,6-hexane trioi.

Particularly preferred isocyanatoaryl sulfonic acids are the sulfonation products of 2,4-tolylene diisocyanate and mixtures of 2,4- and 2,6-tolylene diisocyanate, and also sulfonation products of the di- and polyisocyanates, which are obtained by phosgenation of aniline / formaldehyde condensates. These mixtures contain, in particular, 4,4'-diisocyanatodiphenylmethane and 2,4'-diisocyanatodiphenyimethane as well as higher core homologues of these products. It is basically irrelevant with which sulfonating agents the isocyanato-arylsulfonic acids have been produced. Suitable sulfonating agents are, for example, sulfur trioxide, oleum, sulfuric acid, complexes of sulfur trioxide with Lewis bases which contain oxygen, nitrogen or phosphorus atoms. However, other known sulfonating agents such as chlorosulfonic acid and acyl sulfates, for example acetyl sulfate or reaction products of acid anhydrides with sulfuric acid or oleum can also be used. Side reactions, e.g., for the production of only partially sulfonated isocyanates, e.g. Urea or biuret formation or the partial conversion of isocyanate groups into carbamic acid chloride groups or acylamide groups in general does not matter, so that in these cases, for example, sulfuric acid, chlorosulfonic acid or acetyl sulfate can be used without further ado. In contrast, sulfur trioxide or its complexes, for example according to DE-A 2510693, is preferably used for the production of highly sulfonated polyisocyanates. It follows that, in particular, aromatic polyisocyanatarylsulfonic acids based on tolylene diisocyanate or diphenylmethane diisocyanate are preferred which contain urea or biuret groups.

Solutions and dispersions of isocyanato-arylsulfonic acids in non-sulfonated liquid polyisocyanates are particularly preferred. Such products are obtained, for example, with partial sulfonation of aromatic polyisocyanates. In general, partial sulfonation of chemically uniform diisocyanates or binary isomer mixtures gives suspensions, while partial sulfonation of multicomponent mixtures produces homogeneous solutions. For the process according to the invention it is basically irrelevant whether solutions or suspensions are used. Tellsulfonated polyisocyanate mixtures such as those obtained by phosgenation of aniline-formaldehyde condensates and described in German Offenlegungsschriften 2,227,111, 2,359,614 and 2,359,615 are very particularly preferred. Suspensions of diisocyanatotoluene-sulfonic acid dimers and diisocyanatodiphenylmethane sulfonic acid dimers in diisocyanatotoluene or diisocyanatodiphenylmethane are also particularly preferred.

The isocyanatoarylsulfonic acids to be used in the process according to the invention or their mixtures with unsulfonated aromatic polyisocyanates are prepared by the known processes of the prior art or in analogy to the known Ver drive the state of the art, as it is for example from the publications already mentioned. or from U.S. Patent No. 3,826,769

In the process according to the invention, solutions or suspensions of the above-mentioned isocyanatoaryisulfonic acids in aliphatic or cycloaliphatic polyisocyanates or also aromatic can also be used. aliphatic or cycloaliphatic monoisocyanates are used. Examples of such isocyanates can be found in US Pat. No. 3,963,679.

The type and quantity ratios of the isocyanates to be used in the process according to the invention and their degree of sulfonation are expediently chosen so that the equivalence ratio of (if present in part in dimerized form) isocyanate groups to sulfonic acid groups is greater than 1.1, and in particular between 1.05 and 50.1, preferably between 2-1 and 30: 1, particularly preferably between 2: 1 and 12: 1.

Another group of isocyanato sulfonic acids preferred according to the invention are the aromatic mono-, di- or polyisocyanates described in DE-A 2 615 876, which contain more than one sulfonic acid group (in particular 2 or 3 sulfonic acid groups). In this case, the preferred ratio of isocyanate to sulfonic acid groups is between 0.5: 1 and 1.2: 1.

In the process according to the invention, as oxiaranes, any organic compounds which have at least one epoxy group and are optionally also substituted with isocyanate or hydroxyl groups, but are otherwise largely inert under the reaction conditions under which the oxirane / sulfonic acid addition takes place, can be used. Monoepoxides of the molecular weight range 44-400 corresponding to this definition are preferably used in the method according to the invention. Examples of suitable monoepoxides are ethylene oxide, propylene oxide, butene-1,2-oxide, butene-2,3-oxide, 1,4-dichlorobutene-2,3-oxide, styrene oxide, 1,1,1-trichloropropene-2,3- oxide, 1,1,1-trichlorobutene-3 4-oxide, 1,4-dibromobutene-2,3-oxide, epichlorohydrin, epibromohydrin, glycid, glycerin mono-glycidyl ether, isobutene oxide, p-glycidyl styrene, N-glycidyl carbazole, cyanoethyl glycated ether , Tri-ethyl glycidyl ether, chloroethyl glycidyl ether, bromoethyl glycidyl ether, vinyl oxirane, 3,4-dichlorobutene 2-oxide, 2- (1-chlorovinyl) oxirane, 2-chloro-2-vinyl oxirane, 2,3-epoxypropylphosphonic acid diethyl ester, 3,4- Bis-hydroxy-butene-1,2-oxide, 2-methyl-2-vinyl-oxirane, 2- (1-methylvinyl-) oxirane. Esters of glycid with monocarboxylic acids, e.g. Glycidyl acetate, glycidyl chloroacetate, glycidyl dichloroacetate, glycidyl trichloroacetate, glycidyl bromoacetate, glycidyl acrylate, glycidyl methacrylate, glycidyl caproate, glycidyl octoate, glycidyl dodecanoyl, glycidyl ether, glycidyl ether, glycidyl ether, glycidyl glycidyl ether, glycidyl ether, glycidyl ether, glycidyl glycidyl ether , e.g. with phenol and substituted, especially halogenated phenols. The reaction products of hydroxy-oxiranes, in particular of glycid with aliphatic, cycloaliphatic and aromatic mono- and polyisocyanates, are also very suitable.

To increase the molecular weight and the functionality of the products prepared according to the invention, di- and polyepoxides can also be used, if appropriate in part, for example epoxidation products of aliphatic and cycloaliphatic diolefins, epoxidized polybutadienes or butadiene copolymers or polyglycidyl esters, such as, for example, by reacting a dicarboxylic acid or by Reaction of cyanuric acid with epichlorohydrides or dichlorohydrin can be obtained in the presence of alkali.

Polyglycidyl ethers, such as those obtained by etherifying a dihydric or polyhydric alcohol, a diphenol or a polyphenol with epichlorohydrin or di-chlorohydrin in the presence of an alkali, are preferably used. These compounds can differ from glycols, such as ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,4,6-hexanetriol, glycerol and in particular from Diphenols or polyphenols such as resorcinol, pyrocatechol, hydroquinone, phenolphthalein, phenol-formaldehyde condensation products of the novolak type, 1,4-di-hydroxynaphthalene, dihydroxy-1,5-naphthalene, bis- (hydroxy-4-phenyl) methane . Epoxy resins which are produced from polyphenols and are marketed under the trade name Novolak resins are also particularly suitable.

Further glycidyl ethers suitable according to the invention can be found in British Patents 1,017,612, 1,024,288, 772,830 and 816,923. Further epoxides which can be used according to the invention are described in Houben-Weyl, 1963, Volume XIV / 2, pages 462 to 538.

A compilation of technically important polyoxiranes can be found in H. Batzer and F. Lohse: Introduction to macromolecular chemistry, Hüthig & Wepf Verlag Basel, Heidelberg 1976, pp. 44-53.

Suitable oxetanes in the process according to the invention are any organic compounds which have at least one oxetane ring and are optionally substituted by isocyanate or hydroxyl groups, but are otherwise largely inert under the reaction conditions under which the oxetane / sulfonic acid addition takes place. Preferred oxetanes are monooxetanes of the molecular weight range 58-400 corresponding to this definition. Suitable oxetanes can be found, for example, in German Auslegeschrift 1,668,900, columns 3 and 4.

Of course, the oxetane analogs of the glycid derivatives listed above can also be used, e.g. 3-ethyl-3-acryloxy-oxetane, 3-ethyl-3-methacryloxyoxetane, 3-methyl-3-trichloroacetoxy-oxetane, 3-methyl-3-ß-cyanoethoxymethyl-oxetane, 3-ethyl-ß-cyanoethoxymethyloxetane, 3- Ethyl 3-phenoxymethyl oxetane.

Among the di- and polyoxetanes that can be used according to the invention, the reaction products of 3-alkyl-3-hydroxymethyl-oxetanes with di- and polycarboxylic acids, as well as with di- and polyisocyanates, are of particular importance. The di- and polyethers of the hydroxyoxetanes, which are divided from aliphatic, cycloaliphatic and aromatic diols and polyols, are also very suitable.

The oxiranes are preferred as starting materials in the process according to the invention over the oxetanes. Particularly preferred oxiranes are ethylene oxide, propylene oxide, styrene oxide, 1.1 l of trichlorobutene-3,4-oxide and epichlorohydrin. The preferred oxetane is 3-hydroxymethyl-3-ethyloxetane.

The quantitative ratio between polyhydroxy compounds and isocyanatosulfonic acid is usually chosen so that OH-functional products with a molecular weight below 12,000 and preferably below 6,000 are formed. A molar excess of hydroxy-functional components is therefore used, with at least 1.5 OH groups and SO ₃ H groups being to be accounted for by one NCO group. NCO groups are not only to be understood as NCO groups present in free form but also as dimerized NCO groups present in the form of uretdione groups. It is particularly preferred to only partially modify the hydroxy-functional compounds used as starting material with sulfonic acid groups, it being possible to use up to 30 OH groups and SO ₃ H groups on one NCO group. An equivalent ratio of OH group to NCO group between 2 and 20 is preferred.

The quantitative ratios mentioned essentially apply to reactions which are carried out using di- or polyisocyanates and which lead directly to polyhydroxy compounds modified by sulfonic acid groups, which, after reaction with oxiranes or oxetanes, give the polyhydroxy compounds according to the invention of increased functionality.

In the context of the present invention, however, monoisocyanates which contain 1 to 3 sulfonic acid groups can also be used. These monoisocyanates can, however, also be used in equivalence with the starting hydroxyl compounds in molar amounts, with all OH functions being reacted with isocyanate groups in the latter case. Polysulfonic acids are obtained, which are then reacted with oxiranes or oxetanes to give new polyhydroxy compounds. According to this procedure, products can be obtained whose OH functionality is the same as that of the starting compounds used, but whose reactivity changes, for example, is reduced.

The reaction of the starting hydroxy compounds with the isocyanates containing sulfonic acid groups takes place in principle in a known manner. In general, the hydroxy compounds are introduced and the isocyanate component is added with mixing. If the isocyanate is liquid, as is the case, for example, with partially sulfonated MDI types, the mixing of the components and the subsequent reaction can readily take place at room temperature or at a slightly elevated temperature. The choice of temperature in this case depends exclusively on the viscosity of the reaction mixture and on the desired duration of the reaction. When using solid isocyanatoaryl, mono- or polysulfonic acids, a suspension is primarily formed during the mixing and it is advisable to carry out the reaction at a temperature at which the solid isocyanate dissolves rapidly.

Temperatures between 40 and 180 ° C., in particular 60 and 120 ° C., are expedient for this. In particular when relatively low molecular weight polyhydroxy compounds are used exclusively, temperatures above 120 ° C. to approximately 200 ° C. are preferred in order to avoid the reaction mixture becoming solid during the reaction. Solid isocyanatosulfonic acids are particularly preferably used in the form of suspensions, pastes or wet powders, using inert solvents, as described in DE-A-2 640 103.

Solid isocyanatosulfonic acids can also be used in the form of solutions in organic solvents, liquid esters of an inorganic or organic acid of phosphorus being preferred as solvents (DE-A-2 650 172).

In addition, any inert solvents such as hydrocarbons, halogenated hydrocarbons, ethers, esters and ketones can of course be added to the reaction mixture. However, the reaction in the absence of solvents or with the small amounts of solvents which are used for pasting or dissolving solid isocyanatosulfonic acids is preferred.

The reaction of the introduced sulfonic acid groups with oxiranes or oxetanes can be carried out either after the reaction of all the isocyanate groups in a second reaction stage or else simultaneously or overlapping with the urethanization reaction. A simultaneous reaction is particularly suitable when the OH groups of the starting components are primary, whereas the OH groups resulting from the epoxy reaction are secondary. Under these conditions, a reaction of secondary OH groups with isocyanate groups can only be expected to a minor extent.

The reaction products according to the invention can therefore in principle also be prepared in a one-pot process, with hydroxy compounds, isocyanate component and oxirane or oxetane being mixed and reacted simultaneously. This method is also particularly suitable for poorly soluble isocyanatosulfonic acids, since the presence of oxygen Heterocycles increase the dissolution rate.

The oxiranes or oxetanes or their amounts used in the process according to the invention are selected such that the equivalent ratio of the epoxy or oxetane groups to sulfonic acid groups is between 0.2: 1 and 5: 1, preferably between 0.6: 1 and 2: 1. At an equivalent ratio of _< 1: 1, the SO ₃ H groups present are only partially esterified, so that the process products according to the invention still have free sulfonic acid groups, so that the hydrophilicity of the process products according to the invention caused by these sulfonic acid groups is within the range of 0 due to the equivalent ratio mentioned , 2: 1 to 1: 1 can be varied. Of course, the epoxy or oxetane component can also be used in excess, for example to ensure quantitative esterification of the sulfonic acid groups when using mono-epoxides or mono-oxetanes, or to use more than one epoxy or oxetane group having compounds to incorporate free epoxy or oxetane groups into the process products according to the invention. In particular, epoxy groups incorporated in this way can be used for subsequent reactions, such as trimerization of the isocanate groups, oxazolidone formation or amine crosslinking.

Free sulfonic acid groups can also be completely or partially neutralized, for example with tert. Amines or inorganic bases.

An excess of monoepoxide or monooxetane which may be used can, if desired, be removed from the process product of the invention by distillation after the process according to the invention has ended.

The process according to the invention is very simple to carry out and is generally carried out in the temperature range from 0-190 ° C., preferably 20-140 ° C.

In the case of a discontinuous procedure, the mixture or reaction product of the hydroxy component and polyisocyanate containing sulfonic acid groups is preferably introduced into a stirred vessel at room temperature and the epoxide or oxetane is stirred in. The reaction generally begins immediately with self-heating. If the proportion of sulfonic acid groups is more than about 10%, it may be appropriate to carry out the reaction at lower temperatures, e.g. perform between 0 and 20 ° C and, if necessary, work with cooling. However, such a measure is generally not necessary, since heating the reaction mixture to, for example, 140 ° C. or above is not a disadvantage. If value is placed on a rapid reaction within a short time, and in the case of using epoxides and oxetanes or viscous isocyanates which are liquid at room temperature, it may be expedient to carry out the reaction at elevated temperature, for example between 40-140 ° C., in In special cases the temperature can be up to around 190 ° C.

Gaseous epoxides are expediently introduced with stirring. The reaction is preferably carried out without solvent, but it is of course also possible in the presence of inert solvents, e.g. Dichloroethane, chloroform, tetrachloroethane, trichlorofluoromethane, acetone, toluene, chlorobenzene.

A particularly strong increase in functionality can be achieved by using di- or polyoxiranes or the corresponding oxetanes, in particular if work is carried out approximately in equivalence to the sulfonic acid groups present. It is easily possible to achieve OH functionalities of 4 to 8 with this type of operation. However, it is also possible to set a functionality below 4 if monoisocyanatoarylmonosulfonic acids and / or monofunctional alcohols are used at least in part.

Compounds which are particularly suitable for increasing the functionality are also oxiranes and oxetanes with OH groups, e.g. Glycid, 3-methyl-3-hydroxymethyl-oxetane, 3-ethyl-3-hydroxymethyl-oxetane. Depending on the desired reactivity of the OH-functional short chain, oxiranes or oxetanes will be preferred. While oxetanes generally supply primary OH groups, the use of oxiranes usually leads to secondary or even tertiary OH groups. Only ethylene oxide gives a primary OH group, glycid simultaneously introduces a primary and a secondary OH group within a short chain.

If di- or polyoxiranes are used in molar excess amounts so that only some of the epoxy groups react with sulfonic acid groups, polyhydroxy compounds are obtained which still have free epoxy groups which can either be reacted with, for example, carboxylic acids or carboxylic anhydrides, or as reactive resins can be used in the context of epoxy chemistry.

The process products according to the invention are valuable starting materials for the production of polyurethane plastics by the isocyanate polyaddition process. They are suitable, for example, for the production of compact or cellular elastomers, flexible foams, semi-rigid foams and rigid foams, in particular when high demands are placed on the crosslinking density, the fire behavior or the degradability. Thus, the polyhydroxy compounds according to the invention are suitable, for example, for the production of upholstery materials, mattresses, elastic underlays, car seats, damping materials, shock absorbers, construction materials, soundproofing insulations, moisture-absorbing materials, for example in the hygiene sector, for the production of substrates for growing plants, and for heating and Cold protection. They are particularly suitable Polyhydroxy compounds according to the invention for the production of inorganic-organic plastic, for example in analogy to the procedures described in DBP 2 310 559, DE-A-2 227 147, 2359608, and for surface coatings, impregnations and adhesives.

A particular advantage of the hydroxy compounds according to the invention is their increased polarity. In contrast to pure polypropylene glycol ethers, for example, these products are well tolerated with low molecular weight glycols such as ethylene glycol, diethylene glycol, 1,4-butanediol, glycerin. Mixtures are homogeneous and therefore stable in storage. For the production of polyaddition products with favorable fire behavior, the reaction of the polyhydroxy compounds according to the present invention with polyisocyanates containing sulfonic acid ester groups is particularly favorable.

Such polyisocyanates containing sulfonic acid or sulfonic acid ester groups are often not very compatible due to their high polarity with hydrophobic, long-chain polyethers, so that segregation effects occur which may make a polyaddition reaction impossible. If such polyethers according to the present invention are modified with sulfonic acid ester groups, there is usually good compatibility with polyisocyanates containing sulfonic acid or sulfonic acid ester groups.

example 1 (a) Preparation of the Isocyanatoarylsulfonic Acid

1914 g (11 mol) of tolylene disisocyanate (mixture of isomers 2.4: 2.6 = 80:20) are reacted at 23-30 ° C. in the course of about 20 hours with stirring with 335 g (4.2 mol) of sulfur trioxide, where a viscous suspension of the dimeric tolylene diisocyanate monosulfonic acid is formed in the toluene diisocyanate. The sulfur trioxide is released from heated 65% oleum by means of a weak nitrogen stream and diluted in gaseous form with nitrogen and passed onto the surface of the stirred isocyanate. The suspension obtained is diluted with 500 ml of toluene, suction filtered, and the solid residue is suspended twice with 500 ml of toluene and suction filtered. The toluene-moist product is filled. Yield 1285 g, toluene content 23%, dry matter 990 g, corresponding to 93% of theory.

The product is a slightly moist powder that can be handled very well without dusting. It is easy to fill and refill, does not cake and does not stick to the spatula.

b) Preparation of a polyether diol modified by sulfonic acid groups:

200 g (0.1 mol) of a linear difunctional polypropylene glycol with a molecular weight of 2000 are stirred at 50-60 ° C. with 16.5 g (0.05 mol) of the product prepared according to a). After 5 hours a homogeneous melt is formed which is free of NCO groups. After adding 4.6 g (0.05 mol) of epichlorohydrin, the mixture is stirred at 60 ° C. for 1 hour. Viscosity at 25 ° C: 2 800 mPas.

Average functionality of the product: 3.

Example 2

The procedure is as in Example 1, but 8.5 g (0.025) bisphenol A diglycidyl ether are added instead of the epichlorohydrin. Viscosity at 25 ° C: 50,000 mPas.

Average functionality of the product: 6

Example 3

240 g (0.12 mol) of a linear polypropylene glycol with a molecular weight of 2000 are stirred at 30 ° C. with 33 g (0.1 mol) of the product prepared according to Example 1 a). A white suspension is obtained, which gradually changes into a clear liquid at 60 ° C. After 9.25 g (0.1 mol) of epichlorohydrin has been stirred in, the mixture is stirred at 40-50 ° C. for a further 30 minutes.

Viscosity at 25 ° C: 25,000 mPas.

Example 4

300 g (0.1 mol) of a trifunctional polypropylene glycol of molecular weight 3000 started on trimethylolpropane are stirred at room temperature with 16.5 g (0.05 mol) of the product prepared according to 1 a). After heating to 60 ° C, a clear liquid gradually emerges, into which 4.6 g (0.05 mol) of epichlorohydrin is stirred.

Viscosity at 25 ° C: 3400 mPas

Example 5

In a modification of Example 4, the epichlorohydrin is stirred in immediately after the isocyanate. The mixture is stirred for 90 minutes at room temperature, the isocyanate partially dissolving. The mixture is then heated to 60 ° C. and stirred at this temperature for 7 hours. A clear light brown liquid is obtained which no longer contains any NCO groups. Viscosity at 25 ° C: 4500 mPas. Light brown, clear liquid.

Medium functionality: 5

Example 6

The procedure is as in Example 5, but using 3.7 g (0.05 mol) of glycide instead of epichlorohydrin. Pale yellow cloudy liquid.

Viscosity at 25 ° C: 4500 mPas

Medium functionality: 6

Example 7

The procedure is as in Example 5, but using 5.8 g of 3-ethyl-3 hydroxymethvloxetane instead of the epichlorohydrin. The mixture was stirred at 60 ° C. for 8 hours, at 80 ° C. for 6 hours, at 95 ° C. for 6 hours and at 120 ° C. for 2 hours. 4 g of undissolved isocyanate were filtered off. Brown, green fluorescent liquid.

Viscosity at 25 ° C: 4000 mPas

Medium functionality: 6

Example 8

200 g (0.2 mol) of a linear difunctional polypropylene glycol with a molecular weight of 1000 are stirred at 70 ° C. with 33 g (0.1 mol) of the product prepared according to Example 1a, which is suspended in 30 g of toluene. After 1 hour a clear melt has formed, after 4 hours there are no more NCO groups (IR spectrum). Toluene at 70 ° C i. Vac. withdrawn and the reaction product at 25 ° C with 7.4 g (0.1 mol) of glycid stirred.

Viscosity at 25 ° C: 11,000 mPas

Average functionality of the product: 4

OH number: 106

Acid number (ester cleavage): 14

Example 9

The procedure is analogous to Example 8, but using 123 g (0.2 mol) of a linear polyethylene glycol of molecular weight 615.

Viscosity at 25 ° C: 30000 mPas

Average functionality: 4

OH number: 136

Acid number (ester cleavage): 26

Example 10

The procedure is analogous to Example 8, but using 80 g (0.2 mol) of octaethylene glycol.

Viscosity at 25 ° C: 120000 mPas

Average functionality: 4

OH number: 168

Acid number (ester cleavage): 42

Example 11 1

20 g of the product obtained according to Example 8 and 8 g of the product described below as polyisocyanate A are mixed, a homogeneous white-yellow paste being produced. After 4 hours, a plastic, high molecular mass has formed which crosslinks to an elastomer for a further 2 hours.

If the same experiment is carried out with 0.3 g of tin dioctoate, the mass is crosslinked as early as 2 hours after mixing. The cross-linked elastomer is homogeneous, tack-free and has good tensile strength.

Comparison test

Example 11 is repeated with 20 g of the polypropylene glycol of MW 1000 used as the starting material in Example 8 and 8 g of the product described below as polyisocyanate A. A two-phase mixture is obtained, the dark, heterogeneous isocyanate phase of which settles out muddy. The mixture is mixed several times by stirring within 5 hours, but phase separation always occurs again after a few minutes. After 8 hours the mixture is still liquid.

If the same experiment is carried out with 0.3 g of tin dioctoate, an inhomogeneous solid product with a crumbly appearance is formed immediately after mixing in a strongly exothermic reaction. The product is sticky and without strength.

Polyisocyanate A

So much diisocyanatodiphenylmethane is distilled off from the crude phosgenation product of an aniline-formaldehyde condensate that the distillation residue at 25 ° C has a viscosity of 50 mPas (2-core fraction: 68% by weight; 3-core fraction: 16% by weight). -%; proportion of higher core polyisocyanate: 16% by weight; NCO content: 32% by weight). On the surface of 3800 g of this product a mixture of sulfur trioxide and nitrogen is introduced until 102 g of sulfur trioxide have been taken up by the isocyanate mixture. The product obtained has a viscosity of 120 mPas and a sulfur content of 1.05%.

1850 g of this sulfonated polyisocyanate are mixed with 35.2 g of propylene oxide at room temperature within 30 minutes. The mixture is then stirred at 25-30 ° C for 4 hours. After 20 days, the polyisocyanate obtained, modified with sulfonic acid ester groups, has a viscosity of 490 cP and a sulfur content of 1.03%.

Claims (5)

1. Compounds containing at least two hydroxyl groups and at least one sulphonic acid ester group and having an average molecular weight of from 300 to 12,000, in which at least one hydroxyl group is present in the form of a urethane aryl sulphonic acid hydroxyalkyl ester.

2. Compounds according to Claim 1, characterised by at least one OH-functional long chain, which contains from 6 to 400 chain members and at least one OH-functional short chain which contains 2 to 3 chain members which is attached to a branching point through a sulphonic acid ester residue and at least one at least trifunctional aryl radical as the branching point.

3. Compounds according to Claim 2, characterised by at least one OH-functional long chain containing from 20 to 300 chain members.

4. A process for producing compounds containing at least two hydroxyl groups and at least one sulphonic acid ester group and having an average molecular weight of from 300 to 12,000, in which at least one hydroxyl group is present in the form of a urethane aryl sulphonic acid hydroxyalkyl ester, characterised in that compounds containing at least two hydroxyl groups and having a molecular weight of from 62 to 10,000 are reacted at from 0 to 190°C with aromatic isocyanatosulphonic acids and then with oxiranes and/or oxetanes, the equivalent ratio of the total quantity of isocyanate groups (including the isocyanate groups optionally present in dimerised form) to sulphonic acid groups amounting to from 0.5:1 to 50:1, the equivalent ratio of the sum of the hydroxyl groups in the compounds containing at least two hydroxyl groups and the sulphonic acid groups to NCO groups amounting to from 1.5-1 to 30:1 and the equivalent ratio of the oxirane or oxetane groups to sulphonic acid groups amounting to from 0.2:1 to 5:1.

5. The use of the compounds according to Claim 1 as reaction component for polyisocyanates for the production of polyaddition products and/or polycondensation products.