EP0589942A1

EP0589942A1 - Dihydroxy fatty acids used as polyurethane units

Info

Publication number: EP0589942A1
Application number: EP92911686A
Authority: EP
Inventors: Wolfgang Klauck; Peter Daute
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1991-06-20
Filing date: 1992-06-11
Publication date: 1994-04-06
Also published as: DE4120432A1; US5512655A; WO1993000378A1; JPH06509123A

Abstract

On utilise des acides gras dihydroxyliques et/ou des acides gras polydihydroxyliques en tant que composés portant un groupe ionisable et réactifs par rapport à des isocyanates afin de produire des polyuréthannes contenant des fonctions carboxyles. Les acides gras dihydroxyliques sont obtenus à base de matières premières naturelles et n'ont pas les inconvénients des acides hydroxycarboxyliques utilisés dans l'état antérieur de l'art. Leur utilisation permet en outre d'améliorer le profil des propriétés des polyuréthannes ainsi produits.Dihydric fatty acids and / or polydihydric fatty acids are used as compounds bearing an ionizable group and reactive with respect to isocyanates in order to produce polyurethanes containing carboxyl functions. Dihydroxylic fatty acids are obtained on the basis of natural raw materials and do not have the drawbacks of the hydroxycarboxylic acids used in the prior state of the art. Their use also makes it possible to improve the profile of the properties of the polyurethanes thus produced.

Description

Dihydroxy fatty acids as polyurethane building blocks

The invention relates to the use of dihydroxy fatty acids and / or dihydroxy polyfatty acids as an ionizable group bearing compound which is reactive towards isocyanates for the production of polyurethanes containing carboxy functions. The invention further relates to polyurethanes produced using hydroxy fatty acids and to a process for their preparation.

The dihydroxy fatty acids which can be used in the context of the invention are known from DE-OS 33 18 596. From DE-OS 35 07 505 it is known to use polyether polyesters based on the dihydroxy fatty acids mentioned as a polyol component in the production of polyurethane. Here, however, the carboxylic acid function is esterified, so that ionizable carboxy functions are present neither in the polyol nor in the polyurethane produced therefrom. Accordingly, the dihydroxy fatty acids are not reacted with the isocyanates as free reactive components, but are used to produce a precursor, namely the polyether polyester.

Dihydroxycarboxylic acids are generally known to the person skilled in the art as suitable hydrophilic building blocks for polyurethanes from earlier applications by the applicant, for example from DE-OS 38 27 378. This If they are specified in more detail, dihydroxycarboxylic acids have a relatively low C number and are therefore not derived from natural fatty acids. In addition, it should be noted that of the dihydroxycarboxylic acids mentioned in the literature, those are preferred, or are only described in examples, in which the carboxy group is sterically hindered, at least by a part of the molecule in the alpha position. In DE 2804609 suitable hydroxycarboxylic acids are mentioned and stated that similar acids with sterically hindered carboxy and free unhindered hydroxyl groups are also suitable. Sterically hindered hydroxycarboxylic acids with up to 12 carbon atoms in the alkyl radical are mentioned in GB 2104085.

A dihydroxycarboxylic acid preferred in almost all relevant publications is the particularly strongly sterically hindered dimethylolpropionic acid (DMPA). The reason for the preference of the DMPA is likely to be that the steric shielding of the carboxy group, caused by the methylol groups in the alpha position, tends to cause them to undergo far less side reactions, ie crosslinking, than the person skilled in the art has with a corresponding compound a less sterically protected acid group. For this, the expert accepts some procedural disadvantages in the production of the polyurethanes. These are essentially due to the fact that the DMPA is generally solid at the reaction temperature and therefore has to be comminuted beforehand and the reaction can only take place on the liquid / solid boundary surface, ie in a two-phase system. This generally leads to relatively long reaction times, residues of unreacted DMPA and to the often undesirable circumstance that a large part of the DMPA introduced only reacts when the hydroxyl-containing compounds have already reacted in the liquid phase and thus lead to a non-homogeneous distribution of the carboxy groups in the polyurethane structure. The hard segment character of the DMPA is conditional due to the relatively small molecular size with high functionality, also causes a relatively high viscosity of the polyurethane polymers or prepolymers and can also negatively influence their application properties, such as water resistance.

The object of the invention is to provide polyurethane building blocks which perform the function of the hydroxycarboxylic acids known and used hitherto, without at the same time having the disadvantages described above. In addition, these building blocks should be available on the basis of natural raw materials. Furthermore, the property profile of polyurethane is to be improved by the use of these building blocks according to the invention and the production of the polyurethanes.

The object was achieved by using dihydroxyfatty acids and / or dihydroxy polyfatty acids as an ionizable group-carrying compound which is reactive toward isocyanates for the production of polyurethanes containing carboxy functions.

According to the state of the art, from which ultimately the teaching can be deduced, that the better the carboxylic acid group is shielded or at least sterically hindered by at least one neighboring, better still two neighboring, molecular groups, the better the hydroxycarboxylic acid is appear all the more surprising to experts that it has now been found that dihydroxy fatty acids which do not have a shielding molecular group in the vicinity, in particular not in the alpha position to the carboxy group, lead to particularly good results when used as a building block for the production of polyurethanes . As already mentioned, the dihydroxycarboxylic acids which can be used according to the invention and their preparation are described in DE-OS 33 18596, to which reference is expressly made here.

The dihydroxy fatty acids which can be used according to the invention can be prepared by epoxidizing esters of unsaturated fatty acids, reacting the epoxides with acid catalysis with an excess of an aliphatic diol and / or water with ring opening and, if appropriate, transesterification, and the reaction mixtures at temperatures between 20 ° C. and 60 ° C with Al alihydrox are added and then saponified at temperatures between 80 ° C and 110 ° C to the dihydroxy fatty acids. If the aliphatic diols and / or water are used stoichiometrically or in deficiency when opening the epoxy ring, crosslinking reactions also occur in which dihydroxy polyfatty acids are formed, which in the context of the invention also fall under the term dihydroxy fatty acids.

The dihydroxy fatty acids according to the invention are preferably derived from naturally occurring fatty acids. Therefore, they usually have an even number of carbon atoms in the main chain and are not branched. Those with a chain length of C1 to C26 are particularly suitable. For technical applications, natural fatty acids are mostly used as technical mixtures. These mixtures preferably contain a predominant part of oleic acid. They can also contain further saturated, monounsaturated and polyunsaturated fatty acids. In principle, mixtures of different chain lengths can also be used in the preparation of the dihydroxy fatty acids or dihydroxyalkoxy fatty acids which can be used according to the invention and which may also contain saturated portions or dihydroxyalkoxycarboxylic acids with double bonds. Not only the pure dihydroxy fatty acids are suitable here, but also mixed products obtained from animal fats or vegetable oils after preparation (Ester cleavage, purification stages) contents of monounsaturated fatty acids> 40% preferably> 60. Examples of this are commercially available natural raw materials such as beef tallow with a chain distribution of 67% oleic acid, 2% stearic acid, 1% heptadecanoic acid, 10% saturated acids with chain length C12 to C15, 12% linoleic acid and 2% saturated acids> IQ carbon atoms or e.g. the oil of the new sunflower (NSb) with a composition of approx. 80% oleic acid, 5% stearic acid, 8% linoleic acid and approx. 7% palmitic acid. After opening the ring, these products can be distilled briefly to reduce the unsaturated fatty acid ester content. Further purification steps (eg distillation that lasts longer) are also possible.

The dihydroxy fatty acids according to the invention are preferably derived from monounsaturated fatty acids. For example, 9,10-dihydroxypalmitic acid, 9,10-dihydroxystearic acid and 13,14-dihydroxybehenic acid and their 10,9- and 14,13-isomers are preferred products for the purposes of the invention. Also preferred are monounsaturated fatty acids, which after epoxidation with water or dialcohols (diols) e.g. can be ring-opened via the stage of the methyl ester and then hydrolyzed, such as 4,5-tetradecenoic acid, 9,10-tetradecenoic acid, 9,10-pentadecenoic acid, 9,10-hexadecenoic acid, 9,10-heptadecenoic acid, 6,7-octadecenoic acid, 9,10-octadecenoic acid, 11.12.-octadecenoic acid, 11.12.-eicosenoic acid, 11.12.-docosenoic acid, 13.14.-docosenoic acid, 15.16.-tetracosenoic acid and 9.10.-ximenoic acid. Of these, oleic acid (9/10 octadecenoic acid) is preferred. Both cis and trans isomers of all the fatty acids mentioned are suitable.

Also suitable are dihydroxy fatty acids derived from less common unsaturated fatty acids, such as decyl-12-enoic acid, stilingic acid, dodecyl-9-enoic acid, ricinoleic acid, petroselinic acid, vaccenic acid, elaostearic acid, punicic acid, licanoic acid, parinaric acid, gadoleic acid, Arachidonic acid, 5-eicosenoic acid, 5-docosenoic acid, cetoleic acid, 5,13-docosadienoic acid and / or selacholeic acid.

Dihydroxy fatty acids which have been prepared from isomerization products of naturally unsaturated fatty acids are also suitable. The dihydroxy fatty acids thus produced differ only in the position of the hydroxy or the hydroxyalkoxy groups in the molecule. They are generally in the form of mixtures.

Naturally occurring fatty acids are preferred as starting components in the sense of natural raw materials in the present invention, but this does not mean that synthetically produced carboxylic acids with corresponding C numbers are not suitable. For the purposes of the invention, fatty acids are to be understood as carboxylic acids with a number of C atoms between 8 and 36, regardless of their gain.

The hydroxyalkoxy radical of the dihydroxy fatty acids is derived from the diol which has been used for the ring opening of the epoxidized fatty acid derivative. Preference is given to dihydroxy fatty acids whose hydroxyalkoxy group is derived from preferably primary difunctional alcohols having up to 6 carbon atoms. Suitable diols are propanediol, butanediol, pentanediol and hexanediol, preferably 1,2-ethanediol, 1,4-butanediol and / or 1,6-hexanediol.

Furthermore, polyethylene glycol, polypropylene glycol and / or polytetrahydrofuran diol and their mixed or graft polymerization products are particularly suitable as diol compounds. This applies in particular when these compounds each have a degree of polymerization of about 2 to 20 units.

To prepare the dihydroxy fatty acids according to the invention, epoxidized carboxylic acid esters, for example epoxidized fatty acid methyl, ethyl, propyl or glycerol esters with water and / or the diols from which the hydroxyalkoxy group is to be derived are reacted under ring opening and, if desired, esterification conditions. Known methods can be used for this. It is preferred to submit the diol and / or water provided for the reaction together with an acid catalyst, for example a strong mineral acid, and to add the epoxidized fatty acid derivative continuously or in portions at a reaction temperature between 80 ° C. and 120 ° C. The progress of the reaction can be monitored by titration of the residual epoxide content or by means of spectroscopic methods. When the epoxy groups have been converted, the acidic catalyst is destroyed by neutralization. The resulting dihydroxy fatty acid esters can optionally be freed from excess alcohol by distillation.

In a second stage, the saponification of the dihydroxy fatty acid esters to the dihydroxy fatty acids is usually carried out. The saponification is preferably carried out at temperatures between 40 ° C and 120 ° C in the presence of water with basic catalysis. Suitable bases are the hydroxides of the alkali and / or alkaline earth metals and tertiary amines. After this reaction stage, the dihydroxy fatty acids are obtained as salts (soaps) and can be reacted with strong acids, e.g. Hydrochloric acid or sulfuric acid can be won. It is possible to clean the reaction products by single or, if desired, multiple washing with water. In principle, it is also possible to split the esters, in particular the triglycerides, with water in the absence of catalysts.

In the context of the invention, dihydroxy fatty acids are understood to mean both the ring opening products of epoxidized unsaturated fatty acids with water and the corresponding ring opening products with diols and their crosslinking products with further epoxy molecules. The ring opening products with diols can also be referred to more precisely as dihydroxyalkoxy fatty acids. The hydroxyl groups or the hydroxyalkoxy group are preferably separated from the carboxy group by at least 1, preferably at least 3, in particular at least 6, CH 2 units. The ring opening products mentioned can be used in an outstanding manner for the production of water-dispersible polyurethanes.

The invention further relates to polyurethanes containing ionizable carboxy functions, which can be prepared by reaction

a) on average polyfunctional isocyanates with b) on average polyfunctional polyols and c) an ionizable carboxy functional component and d) if desired a chain extender.

According to the invention, these polyurethanes are characterized in that c) is a dihydroxy fatty acid. The preferred embodiments of these polyurethanes according to the invention include the preferred embodiments of the dihydroxy fatty acids which can be used and which have already been mentioned.

The proportion of c), taking into account the amount and the hydrophilic properties of the other components, is preferably such that the resulting polyurethanes are themselves dispersible in water. An exact quantity is not possible here. If, for example, polyols are used as the starting component, which in themselves already have a relatively high hydrophilicity, it will not be necessary to use as much c) in order to obtain self-dispersible polyurethanes as if largely hydrophobic polyols were used as starting substances. The amount of c) required in each case can therefore only be given via the "self-dispersible" function. The inclined expert in the field of However, polyurethane dispersions - given the quantity and type of the other components - will be able to roughly estimate the necessary amount of c) from his knowledge and experience and / or be able to determine it precisely with just a few tests. Polyurethane dispersions are preferably produced from the self-dispersible polyurethanes. These generally have a solids content of 20 to 70% by weight, in particular 30 to 50% by weight.

A large number of polyol compounds can be used as polyol component b), either alone or as a mixture. The general rule is that these polyols must have at least two isocyanate-reactive hydrogen atoms and should be essentially linear. Suitable here are, for example, polyethers, polyacetals, polycarbonates, polythioethers, polyamides, polyesteramides and / or polyesters, each of which has on average two to at most four reactive hydrogen atoms.

Polycarbonates are understood here to mean polyesters which can theoretically be prepared by esterifying carbonic acid with dihydric or polyhydric alcohols and which have a hydroxyl group on both chain ends. The alcohols and ultimately the polycarbonate diols preferably have an aliphatic structure. Suitable polyhydric alcohols can e.g. be trivalent such as glycerol. However, dihydric alcohols are preferred, especially if these have no less than four and no more than ten carbon atoms. Cyclic and branched chain alcohols are suitable, but linear ones are preferred. The hydroxyl groups can be adjacent, e.g. be arranged in the 1,2 position, or isolated. Diols with terminal 0H groups are preferred.

Examples of polyethers are the polymerization products of ethylene oxide, propylene oxide and butylene oxide and their mixed or Graft polymerization products and the polyethers obtained by the condensation of polyhydric alcohols or mixtures thereof and the polyethers obtained by alkoxylation of polyhydric alcohols, amines, polyamines and aminoalcohols. Also suitable as polyethers are the polytetrahydrofurans described in EP 354 471 and also ethylene-glycol-terminated polypropylene glycols.

As polyacetals such. B. the compounds which can be prepared from glycols such as diethylene glycol, triethylene glycol, hexanediol and formaldehyde are suitable. Suitable polyacetals can also be prepared by polymerizing cyclic acetals.

Among the polythioethers, the condensation products of thiodiglycol with themselves and / or with other glycols, dicarboxylic acids, formaldehyde, aminocarboxylic acids or amino alcohols should be mentioned in particular. Depending on the co-components, the products are polythioethers, polythio mixed ethers, polythioether esters, polythioether ester amides. Such polyhydroxy compounds can also be used in alkylated form or in a mixture with alkylating agents.

The polyesters, polyester amides and polyamides include those obtained from polyvalent saturated and unsaturated carboxylic acids or their anhydrides and polyvalent saturated and unsaturated alcohols, amino alcohols, diamines, polyamines and their mixtures, predominantly linear condensates, e.g. Polyterephthalates. Lactone polyester, e.g. B. caprolactone or from Hydroxycarbon¬ acids can be used. Higher molecular weight polymers or condensates, such as e.g. Polyethers, polyacetals, polyoxymethylenes (it) can be used.

Also polyhydroxyl compounds already containing urethane or urea groups and optionally modified natural polyols such as castor oil can be used. In principle, polyhydroxyl compounds which have basic nitrogen atoms can also be used, e.g. B. polyalkoxylated primary amines or polyesters or polythioethers which contain alkyl diethanola in condensed form. It is also possible to use polyols which can be produced by complete or partial ring opening of epoxidized triglycerides with primary or secondary hydroxyl compounds, for example the reaction product of epoxidized soybean oil with methanol. Copolymers of the polyhydroxyl compounds mentioned can also be suitable, as can their analogs with preferably terminal amino or sulfide groups.

As a rule, those polyol components which are at least predominantly based on natural polyols are also particularly suitable. Such natural polyols are to be understood in particular as castor oil compounds such as castor oil. Triglycerides modified as natural polyols are particularly suitable, as are described, for example, in DE 3246612. These can be prepared by partial ring opening of epoxidized triglycerides of a fatty acid mixture containing at least partially olefinically unsaturated fatty acids with mono- or polyhydric alcohols. The epoxidized carboxylic acid esters preferred in this connection include in particular the triglycerides of the epoxidized naturally occurring fatty acids such as epoxidized soybean oil, in particular with an epoxy oxygen content of 5.8 to 6.8% by weight, high-oleic and / or low-epoxidized sunflower oil , preferably with an epoxy oxygen content of 4.4 to 6.6% by weight, epoxidized linseed oil, preferably with an epoxy oxygen content of 8.2 to 8.6% by weight, and epoxidized tran oil, preferably with an epoxy oxygen content from 6.3 to 6.7% by weight.

Numerous animal and / or are suitable as starting materials for epoxidized carboxylic acid esters for the production of natural polyols vegetable triglycerides such as beef tallow, palm oil, coconut oil, peanut oil, rapeseed oil, cottonseed oil, soybean oil, tran oil, sunflower oil, coriander oil and / or linseed oil. Equally suitable are epoxidized carboxylic acid esters of monohydric alcohols with naturally occurring epoxidized fatty acids such as are obtained, for example, by transesterification reaction of the abovementioned epoxidized triglycerides with monohydric alcohols, which can also be used for ring opening and which are described below can.

The above-mentioned epoxidized compounds can be reacted with alcohols and / or carboxylic acids in a ring-opening manner. In principle, saturated, unsaturated, branched, unbranched, cyclic, aromatic, monohydric primary alcohols can be used to open the ring. Of these, particularly saturated, unbranched, monohydric primary alcohols with 1 to 22 carbon atoms, preferably 8 carbon atoms, and in particular up to 4 carbon atoms, such as methanol, ethanol, propanol and / or butanol, are used. Diols whose one hydroxyl group is etherified or esterified, such as monoalkylethylene glycol, can also be used as monohydric primary alcohols. Furthermore, ring opening products with the abovementioned epoxidized compounds with dihydric, trihydric and / or polyhydric alcohols such as ethylene glycol, propylene glycol, propanediol, butanediol, hexanediol, trimethylolpropane, glycerol, trimethylol ether, pentaerythritol and / or sorbitol and with condensation products such as diglycerin, polyglycerin, polytrimethylolpropane.

All polyfunctional aromatic and aliphatic isocyanates are suitable as isocyanate component a). The suitable polyfunctional isocyanates preferably contain on average 2 to at most 4 NCO groups. Examples of suitable isocyanates are 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), hydrogenated MDI (H ^ MDI), xylylene diisocyanate (XDI), Tetramethylxylylene diisocyanate (TMXDI), 4,4'-

Diphenyldimethylmethane diisocyanate, di- and tetraalkyldiphenylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, the isomers of tolylene diisocyanate (TDI), optionally in a mixture, l-methyl-2, 4-diisocyanato-cyclohexane, l, 6-diisocyanato-2,2,4-trimethylhexane, 1,6-diisocyanate-2,4,4-trimethylhexane, l-isocyanatomethyl-3-isocyanato-l, 5,5- tri ethyl-cyclohexane (IPDI), chlorinated and brominated diisocyanates, phosphorus-containing diisocyanates, 4,4'-diisocyanatophenylperfluoroethane, tetramethoxybutane-l, 4-diisocyanate, butane-l, 4-diisocyanate, hexane-1,6-diisocyanate (HDI), Dicyclohexylmethane diisocyanate, cyclohexane-l, 4-diisocyanate, ethylene diisocyanate, phthalic acid bis-isocyanatoethyl ester, also polyisocyanates with reactive halogen atoms, such as l-chloromethylphenyl-2,4-diisocyanate, 1-bromomethylphenyl-2,6-diisocyanate, 3 , 3-bis-chloromethyl ether-4,4'-diphenyl diisocyanate. Sulfur-containing polyisocyanates are obtained, for example, by reacting 2 mol of hexamethylene diisocyanate with 1 mol of thiodiglycol or dihydroxydihexyl sulfide. Other important diisocyanates are trimethylhexamethylene diisocyanate, 1,4-diisocyanatobutane, 1,2-diisocyanatododecane and di-fatty acid diisocyanate. Interest is sometimes given to blocked polyisocyanates which enable the formation of self-crosslinking polyurethanes, e.g. dimeric tolylene diisocyanate, or polyisocyanates partially reacted with, for example, phenols, tertiary butanol, phthalide, caprolactam.

In a particular embodiment, the isocyanate component partially contains dimer fatty acid isocyanate. Dimer fatty acid is a mixture of predominantly C36 dicarboxylic acids, which is prepared by thermal or catalytic di erization of unsaturated Ciss monocarboxylic acids, such as oleic acid, tall oil fatty acid or linoleic acid. Such dimer fatty acids have long been known to the person skilled in the art and are commercially available. The dimer fatty acid can be converted into dimer fatty acid isocyanates. Technical Dimer fatty acid diisocyanate has on average at least two and less than three isocyanate groups per molecule of dimer fatty acid. The isocyanate component a) preferably consists of more than 30% by weight, in particular at least predominantly, preferably completely, of aliphatic isocyanates. By using aliphatic isocyanates, the mostly undesirable side reaction of carboxy groups with isocyanate groups can be virtually completely prevented. Furthermore, for example, a more controlled course of the reaction when extending the chain in water is possible.

Suitable chain extenders d) with reactive hydrogen atoms include:

the usual saturated and unsaturated glycols, such as ethylene glycol or condensates of ethylene glycol, 1,3-butanediol, 1,4-butanediol, butenediol, 1,2-propanediol, 1,3-propanediol, neopentylglycol, hexanediol, bis- hydroxymethyl-cyclohexane, dioxyethoxyhydroquinone, terephthalic acid bis-glycol ester, succinic acid di-2-hydroxyethylamide, succinic acid di-N-methyl- (2-hydroxy-ethyl) amide, 1,4-di (2-hydroxy-methyl) -mercapto) - 2,3,5,6-tetrachlorobenzene, 2-methylene-propanediol- (1,3), 2-methyl-propanediol- (1,3);

aliphatic, cycloaliphatic and aromatic diamines such as ethylenediamine, hexamethylenediamine, 1,4-cyclohexylenediamine, piperazine, N-methyl-propylenediamine, diaminodiphenylsulfone, diaminodiphenylether, diaminodiphenyldimethylmethane, 2,4-diamino-6-phenophenyldiazineed , Hydrazine, diaminodiphenylmethane or the isomers of phenylenediamine. Furthermore also carbohydrazides or hydrazides of dicarboxylic acids. Amino alcohols such as ethanolamine, propanolamine, butanolamine, N-methylethanolamine, N-methylisopropanolamine;

aliphatic, cycloaliphatic, aromatic and heterocyclic mono- and diaminocarboxylic acids such as glycine, 1- and 2-alanine, 6-aminocaproic acid, 4-aminobutyric acid, the isomeric mono- and diaminobenzoic acids, the isomeric mono- and diaminonaphthoic acids;

water

It should be emphasized that it is not possible to make a strict distinction between the compounds with reactive hydrogen atoms as the polyol component and the so-called "chain extenders" since the transitions between the two classes of compounds are fluid. Compounds that are not made up of several monomer units, but have a relatively high molecular weight, e.g. S.S'-Dibro ^^ '- diaminodiphenylmethane, are counted among the chain extenders, but also pentaethylene glycol, although the composition of the latter is actually a polyether diol.

Special chain extenders with at least one basic nitrogen atom are, for example, mono-, bis- or polyoxalkylated aliphatic, cycloaliphatic, aromatic or heterocyclic primary amines, such as N-methyldiethanolamine, N-ethyl-diethanolamine, N-propyl-diethanolamine, N-isopropyl-diethanolamine , N-butyl-diethanolamine, N-isobutyl-diethanolamine, N-oleyl-diethanolamine, N-stearyl-diethanolamine, ethoxylated coconut fatty amine, N-allyl-diethanolamine, N-methyl-diisopropanolamine, N-ethyl-diisopropanolamine, N-propyl-diisopropanolamine, N-butyl-diisopropanolamine, N-cyclohexyl-diisopropanola in, N, N-dioxethylaniline, N, N-dioxethyltoluidine, N, N-dioxethyl-l-aminopyridine, N, N'-dioxethyl- piperazine, dimethyl bis-oxyethyldrazin, N, N'-bis- (2-hydroxyethyl) -N, N'-diethyl-hexa- hydro-p-phenylenediamine, N-12-hydroxyethyl-piperazine, polyalkoxylated amines such as oxypropylated methyl diethanolamine, furthermore compounds such as N-methyl-N, N-bis-3-aminopropylamine, N- (3-aminopropyl) -N, N'-dimethylethylenediamine, N- (3-aminopropyl) -N-methyl -ethanolamine, N-N'-bis- (3-aminopropyl) -N, N'-dimethylethylenediamine, N, N'-Bϊs (3-aminopropyl) -piperazine, N- (2-aminoethyl) -piperazine, N , N'-bisoxyethyl-propylenediamine, 2,6-diaminopyridine, diethanolaminoacetamide, diethanolamidopropionamide, N, N-bis-oxyethyl-phenyl-thiosemicarbazide, N, N-bis-oxethyl-methyl-semicarbazide, p, p'-bis - aminomethyl-dibenzylethylamine, 2,6-diaminopyridine, 2-dimethylaminomethyl-2-methyl-propanediol-1,3.

Chain extenders with halogen atoms or R-Sθ2θ groups capable of quaternization are, for example, glycerol-1-chlorohydrin, glycerol monotosylate, pentaerythritol-bis-benzenesulfonate, glycerol-monomethanesulfonate, adducts of diethanolamine and chloromethylated isocyanate or chlorinated allylated aromatic or Halogen isocyanates such as N, N-bis-hydroxyethyl-N'-m-chloromethylphenylurea, N-hydroxyethyl-N'-chlorhexylurea, glycerol-mono-chloroethyl-urethane, bromoacetyl-dipropylenetriamine, chloroacetic acid diethanola id. Short-chain diamines and / or dihydroxy compounds which are reactive toward isocyanates are particularly suitable as chain extenders.

Furthermore, the invention relates to a process for the production of polyurethanes according to claims 9 to 12, characterized in that components b) and c) are processed to a homogeneous single-phase system before reaction with a). In contrast to the DMPA which has so far been most preferred in the relevant literature, the dihydroxy fatty acids which can be used according to the invention have the advantage that they are liquid at the reaction temperature. In addition, they can be incorporated into the polyol in a completely homogeneous manner are so that the isocyanate-reactive component is a single-phase system. This in turn results in shorter reaction times and no noteworthy residues of unreacted dihydroxy fatty acid. Furthermore, the dihydroxy fatty acids react with the other reactive components in such a way that they are largely homogeneously distributed in the resulting polyurethane structure. Because the dihydroxy fatty acids have no pronounced hard segment character, the polyurethane polymers or prepolymers produced are less viscous than comparable polymers with DMPA. If, according to the preferred embodiment, the polyurethanes are self-dispersing in water, films can be produced from the dispersions which have a higher water resistance when using dihydroxy fatty acids than when using DMPA when producing the polyurethanes.

There are many possible uses for the polyurethanes according to the invention. They can be used, for example, in 2-component systems, thixotropic pastes or in moisture-curing sealants and adhesives. Their good metal adhesion is particularly noteworthy. Furthermore, the polyurethanes according to the invention can also be processed to give moldings by injection molding or extrusion. The self-dispersible polyurethanes according to the invention are preferably used for the production of aqueous polyurethane dispersions. These in turn can now be used, optionally in admixture with other auxiliary substances, as adhesive, sealing and / or sealing aids.

The present invention is illustrated by the following examples. Examples

Example 1:

Ring opening of epoxystearic acid methyl tester (technical) with ethylene glycol and release of the carboxylic acid

100 kg of epoxystearic acid methyl ester (EP.-O = 4.95%) and 38.3 kg of ethylene glycol were heated to 90 ° C. in the presence of 34 g of concentrated sulfuric acid. The initially exothermic reaction was complete after 1.5 hours (EP.-O = 0.03%). The catalyst acid was neutralized with 160 g of 30% methanolic sodium methylate solution and the crude product was then vacuumed to 200 ° C. (27.7 kg of distillate). This gave a yellow clear liquid (OHZ = 235, VZ = 162, IZ = 7, SZ = 0.7).

2243.2 g of the ring opening product of methyl epoxystearate with glycol were saponified with 1430 g of 20% sodium hydroxide solution at 90 ° C. (reaction time 3 h). 1002.4 g of 20% strength sulfuric acid were then added at 60 ° C., and the organic phase was washed twice with water and dried in vacuo. The product (1870 g) is a yellowish liquid (SZ = 158, VZ = 164, OHZ = 243).

The epoxystearic acid methyl ester was prepared by epoxidation of a oleic acid methyl ester with the following main components in the fatty acid composition: oleic acid (Cιg: l) 73% by weight, linoleic acid (Cχ8: 2) 11% by weight, palmitoleic acid (Ci6: l) 5% by weight , Stearic acid (Cιs: 0) 2 wt .-%. Example 2:

Ring opening of epoxystearic acid methyl ester (technically) with ethylene glycol and release of the carboxylic acid

1019 g of epoxystearic acid methyl ester (Ep.-O = 4.71%) and 637 g of ethylene glycol were heated to 90 ° C. with stirring in the presence of 0.45 g of concentrated sulfuric acid. The initially exothermic reaction was complete after 2 hours (Ep.-O = 0.03%). The catalyst acid was neutralized with 1.8 g of 30% methanolic sodium ethylate solution and the crude product was distilled in vacuo to 210 ° C. (541 g distillate). This gave a yellow, clear liquid (OHZ = 200, VZ = 146, IZ = 11, SZ = 0.4).

1057 g of the ring opening product of epoxystearic acid methyl ester with diethylene glycol were saponified with 480 g of 25% sodium hydroxide solution at 95 ° C. (reaction time 2 h). Then 420 g of 35% strength sulfuric acid were added at 60 ° C. and the organic phase was washed twice with water and dried in vacuo. The product (810 g) is a yellowish liquid (SZ = 145, VZ = 150, OHZ = 212).

Example 3:

Ring opening of epoxystearic acid methyl ester (technical) with 1,6-hexanediol and release of the carboxylic acid

1019 g of epoxystearic acid methyl ester (Ep.-O = 4.71%) and 709 g of 1,6-hexanediol were heated to 90 ° C. in the presence of 0.75 g of concentrated sulfuric acid. The initially exothermic reaction was complete after 3 hours (Ep.-O = 0.03). The catalyst acid was neutralized with 3.5 g of 30% strength methanolic sodium methylate solution and the crude product was distilled in vacuo to 210 ° C. (579 g of distillate). This gave a yellow, clear liquid (VZ = 147, IZ = 11, SZ = 0.4).

1015 g of the ring opening product of epoxystearic acid methyl ester with 1,6-hexanediol were saponified with 465 g of 25% sodium hydroxide solution at 95 ° C. (reaction time 2 h). Then 407 g of 35% sulfuric acid were added at 60 ° C. and the organic phase was washed twice with water and dried in vacuo. The product (939 g) is a yellowish liquid (SZ = 144, VZ = 148, OHZ = 206).

Example 4;

Ring opening of epoxystearic acid methyl ester (technical) with 1,4-butanediol and release of the carboxylic acid

1019 g of methyl epoxystearate (Ep.-O - 4.71%) and 541 g of 1,4-butanediol were heated to 110 ° C. in the presence of 0.45 g of concentrated sulfuric acid. The initially exothermic reaction was complete after 1 hour (Ep.-O = 0.03%). The catalyst acid was neutralized with 2.0 g of 30% methanolic sodium methylate solution and the crude product was distilled in vacuo to 210 ° C. (506 g distillate). This gave a yellow, slightly cloudy liquid (OHZ = 233, VZ = 149, IZ = 7, SZ = 0.5).

977 g of the ring opening product of methyl epoxystearate with 1,4-butanediol were saponified with 513 g of 25% sodium hydroxide solution at 95 ° C. (reaction time 2 h). 448 g of 35% strength sulfuric acid were then added at 60 ° C. and the organic phase was washed twice with water and dried in vacuo. The product (906 g) is a yellowish liquid (SZ = 154, VZ = 154, OHZ = 242).

Example 5:

Opening of epoxystearic acid methyl ester (technical) with Polydiol 300 and release of the carboxylic acid

584 g of epoxystearic acid methyl ester (Ep.-O = 4.71%) and 516 g of Polydiol 300 were heated to 100 ° C with stirring in the presence of 2.6 g of concentrated sulfuric acid. The initially exothermic reaction was complete after 2 hours (Ep.-O - 0.1%) and the product was saponified with 339 g of 25% sodium hydroxide solution at 98 ° C. (reaction time 2 h). After bleaching for 15 minutes with 10 ml of 13% NaOCl solution, 346 g of 35% sulfuric acid were added at 60 ° C. and the organic phase was washed twice with water and dried in vacuo. The product (637 g) is a yellowish wax (SZ = 140, VZ = 147, OHZ = 106).

Example 6:

Ring opening of epoxystearic acid methyl ester (technical) with Polydiol 600 and release of the carboxylic acid

408 g of methyl epoxystearate (Ep.-O = 4.71%) and 720 g of Polydiol 600 were heated to 100 ° C. with stirring in the presence of 4.2 g of concentrated sulfuric acid. The initially slightly exothermic reaction was complete after 4 hours (Ep.-O = 0.1%) and the product was saponified with 238 g of 25% sodium hydroxide solution at 90 ° C. (reaction time 2 h). After 15 minutes of bleaching with 10 ml of 13% NaOCl solution, 209 g of 35% sulfuric acid were added at 60 ° C. and the organic phase was washed twice with water and dried in vacuo. The product is a yellowish wax (SZ = 121, VZ = 124, OHZ = 69). Example 7:

Ring opening of epoxy NSb fatty acid ethyl ester with ethylene glycol and release of the carboxylic acid

693 g of epoxy-NSb fatty acid methyl ester (Ep.-O = 4.62%) and 248 g of ethylene glycol were heated to 100 ° C. with stirring in the presence of 0.2 g of concentrated sulfuric acid. The initially exothermic reaction was complete after 1 hour (Ep.-O = 0.1%). The catalyst acid was neutralized with 0.9 g of 30% methanolic sodium methylate solution and the crude product was vacuum distilled to 200 ° C. (163 g distillate) and then saponified with 160 g of 50% sodium hydroxide solution and 200 ml of water at 90 ° C. (reaction time 3 H). Then 35% sulfuric acid was added at 60 ° C. (to pH = 2), the organic phase was washed twice with water and dried in vacuo. The product is a yellowish liquid (SZ = 150, VZ = 155, OHZ = 238).

Ep.O = epoxy oxygen content in weight

SZ = acid number

VZ = saponification number

OHZ = OH number

Na = sodium content

NSb = fatty acid product from the oil of the new sunflower with an oleic acid content of 85% by weight. The following dispersions were made:

Raw materials Name of the dispersions (in moles)

Dihydroxy fatty acid from Ex. 1 0.5 0.7 / / / / / / / /

Ex. 2 / / 0.5 / / / / / /

Ex. 3 / / / 0.6 / / / / /

Ex. 4 / / / / 0.6 / / / /

Ex. 5 / / / / / 0.5 / / /

Ex. 6 / / / / / / 0.4 / 0.1

Ex. 7 / / / / / / / 0.6 0.4 Ester 1 / / / 0.2 0.3 / / / / PPG 1000 0.4 / 0.2 0.1 / / 0.3 / 0 .4 PPG 425 / / 0.1 0.1 / / 0.1 / 0.1 PPG 2000 / 0.2 / / / / 0.1 / / PTHF 1000 0.1 / / / / / / 0.2 / PTHF 2000 / 0.1 0.2 / 0.1 0.5 / 0.2 / DMPA / / / / / / 0.1 / /

Ethylene diamine 0.2 0.1 / / 0.3 / / / / IPDI 1.3 1.0 / 0.5 1.4 1.3 / 1.0 / TMXDI / / 1.1 0.8 / / 1 .3 / / H12MDI / 0.3 / / / / / 0.3 1.1 MDI / / 0.2 / / / / / /

Triethylamine 0.5 / / 0.2 0.6 / / 0.5 0.4 NaOH / 0.6 0.5 0.3 / 0.5 0.5 / /

Solids content,% by weight 40.939.839.237.636.942.035.143.034.9 acetone,% by weight 10 10/8 10 10/12 18 (Ester 1 prepared from adipic acid, ethylene glycol and hexanediol, the latter in a ratio of 1: 1, with a molecular weight of 2000, calculated via the OH number)

Dispersions A, B, C, D, E, F, G, H, I were prepared by the acetone process at approx. 75 ° C, and dispersions C and G were prepared at approx. 100 ° C without the addition of solvents. The dispersion was started after the theoretical NCO value had been reached, the chain extension with diamines was initiated directly after the dispersion by adding the slide.

The results of the adhesion measurements are listed in the following table. The tensile shear strengths were carried out on test specimens of the dimension 10 × 5 × 0.5 01.3 with a tear speed of 10 cm / min. Before the test specimens were glued, they were stored for 3 days at room temperature. The overlap of the test specimens was 2 cm x 5 cm (adhesive surface). This test procedure was developed based on DIN 53254.

Tensile shear strengths in N / cπr

ABCDEFGHI wood / wood 8.2 6.5 6.8 7.9 8.4 7.2 6.1 7.2 7.6 wood / PVC 3.5 3.8 3.5 4.2 5.8 4 , 6 2.8 4.3 2.2

Wood / ABS 3.4 3.9 2.8 4.0 5.5 4.0 2.2 3.9 1.9 wood / aluminum 7.5 6.9 7.1 7.0 7.0 6. 2 6.9 7.0 8.0 Wood: beech wood

PVC: polyvinyl chloride

ABS: acrylonitrile-butadiene-styrene terpolymer

Alu aluminum

EDA: ethylenediamine

IPDI: isophorone diisocyanate

TEA: triethylene amine

PPG: polypropylene glycol - Give the numbers

PTHF: Polytetrahydrofurandiol | - the average molecular weight.

Claims

Patent claims

1. Use of dihydroxy fatty acids and / or dihydroxy polyfatty acids as an ionizable group bearing compound which is reactive towards isocyanates for the production of polyurethanes containing carboxy functions.

2. Use according to claim 1, characterized in that the di-hydroxy fatty acids can be produced by ring opening epoxidier¬ ter monounsaturated fatty acids with water.

3. Use according to claim 1, characterized in that the dihydroxy fatty acids can be prepared by ring opening of epoxidized monounsaturated fatty acids with diols.

4. Use according to claim 3, characterized in that the diol used for ring opening is 1,2-ethanediol, 1,4-butanediol and / - or 1,6-hexanediol.

5. Use according to claim 3, characterized in that the diol used for ring opening is polyethylene glycol, polypropylene glycol and / or polytetrahydrofuran diol - in particular in each case with a degree of polymerization of 2 to 20 units.

6. Use according to at least one of the preceding claims, characterized in that the epoxidized monounsaturated fatty acids have a chain length of C14 to C26.

7. Use according to at least one of the preceding claims, characterized in that the epoxidized monounsaturated fatty acids are technical mixtures of natural fatty acids - in particular with a predominant proportion of oleic acid.

8. Use according to at least one of the preceding claims, characterized in that the dihydroxy fatty acids are used for the production of polyurethanes which are self-dispersible in water.

9. Polyurethanes containing ionizable carboxy functions, producible by reacting a) on average multifunctional isocyanates with b) on average multifunctional polyols and c) a component introducing ionizable carboxy functions and d) if desired, a chain extender, characterized in that c) is a dihydroxy fatty acid.

10. Polyurethanes according to the preceding claim, characterized by at least one of the characterizing parts of claims 2 to 7.

11. Polyurethanes according to at least one of the two preceding claims, characterized in that a) consists of more than 30% by weight, in particular at least predominantly, preferably completely, of aliphatic isocyanates.

12. Polyurethanes according to at least one of the preceding claims, characterized in that the proportion of reacted c) in the polyurethane is selected so that it is self-dispersible in water.

13. A process for the preparation of polyurethanes according to claims 9 to 12, characterized in that components b) and c) are processed to a homogeneous single-phase system before reaction with a).