EP2318449A1

EP2318449A1 - Viscosity reducing agents for polyether polyols

Info

Publication number: EP2318449A1
Application number: EP09782321A
Authority: EP
Inventors: Peter Daute; Bernhard Bartnick
Original assignee: Emery Oleochemicals GmbH
Current assignee: Emery Oleochemicals GmbH
Priority date: 2008-08-28
Filing date: 2009-08-28
Publication date: 2011-05-11
Also published as: CN102203157B; JP2012500882A; US20110237770A1; MY160012A; US20130310478A1; DE102008044706A1; CN102203157A; US20140179816A9; BRPI0917879A2; WO2010023271A1; JP5767111B2

Abstract

The present invention relates to a method for producing a polyurethane, which contains the process steps of: i) providing a polyisocyanate component containing at least one polyisocyanate, ii) providing a polyol component containing at least one polyether polyol, polyester polyol or a mixture of a polyether polyol and a polyester polyol, wherein the polyol component contains a polyester of a polyol and a monocarboxylic acid, iii) bringing the polyisocyanate component into contact with the polyol component with formation of a polyurethane. The invention also relates to the polyurethane obtainable by this process, a polyol component containing a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, a method for producing a polyol component, which contains a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, a polyol component obtainable by this method and containing a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, the use of this polyol component containing a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, as well as the use of a polyol ester.

Description

Viscosity reducer for polyether polyols

The present invention relates to a process for producing a polyurethane, the polyurethane obtainable by this process, a polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, a process for producing a polyether polyol, a polyester polyol or a blend of a polyol component containing a polyether polyol and a polyester polyol, the polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, the use of this one polyether polyol, a polyester polyol or a blend obtainable by this process from a polyether polyol and a polyester polyol-containing polyol component and the use of a polyol ester.

Polyurethanes have long been known and described many times. They can, depending on the nature of the starting components used to prepare the polyurethane, be present as a foamed or unfoamed plastic. If it is a foamed plastic, it may in turn be present as a permanently elastic flexible foam, which is suitable, for example, for the production of sports shoe soles or sleeping mattresses, or as a rigid foam which can be used, for example, as a mounting foam. For example, Reinhard Leppkes in Polyurethanes - Material with Many Faces gives an overview of the possible uses of polyurethanes ", 5th edition, Verlag Moderne Industrie, 2003.

The preparation of polyurethanes is well known from the prior art. This is usually done by reacting polyisocyanates, in which case diphenylmethane diisocyanate (MDI) and in particular mixtures of diphenylmethane diisocyanate and the higher homologs polyphenylene polymethylene polyisocyanates (crude MDI) are usually used. fertilize with at least two hydrogen atoms reactive with isocyanate groups. A summary of the production and application of rigid polyurethane foams can be found, for example, in the Kunststoff-Handbuch, Volume 7, Polyurethane 1st Edition 1966, edited by Dr. med. R. Vieweg and dr. A. Höchtlen, 2nd edition 1983, edited by Dr. med. Günter Oertel, and 3rd edition 1993, edited by Dr. med. Günter Oertel, Carl Hanser Verlag, Munich, Vienna.

Polyols, in particular polyether polyols and polyester polyols, are frequently used as the compound having at least two hydrogen atoms which are reactive toward isocyanate groups both in the production of rigid foams and in the production of flexible foams, the polyether polyols being prepared by reacting alkylene oxides, for example ethylene oxide or propylene oxide xid are obtainable with starter molecules, such as water, amines or alcohols, while the polyester polyols are usually obtained by condensation of polyfunctional alcohols with polyfunctional carboxylic acids. Processes for the preparation of polyether and polyester polyols are described, for example, in WO-A-2008/084054. However, the polyester or polyether polyols thus obtained generally have a very high viscosity, so that they can be mixed only very poorly with the polyisocyanates. However, if the polyol component and the polyisocyanate component can not be mixed homogeneously enough, this also has disadvantages for the resulting polyurethane.

A further disadvantage of the processes known from the prior art for the preparation of polyurethanes based on polyether or polyester polyols is that the reaction mixture obtained by mixing the polyol component with the polyisocyanate component also has a comparatively high viscosity their use in the so-called reaction injection molding {^ injection injection molding method "or in short especially when it comes to infesting small cavities.

It is an object of the present invention to overcome the disadvantages of the prior art in connection with the production of polyurethanes from polyisocyanates and polyether or polyester polyols.

In particular, the object of the present invention was to provide a process for producing a polyurethane based on polyisocyanates and polyether or polyester polyols, with the aid of which these components can be more easily mixed with one another.

A further object of the present invention is to provide a process for the preparation of a polyurethane based on polyisocyanates and polyether or polyester polyols, with the aid of which polyurethanes having improved product properties in comparison with corresponding polyurethanes obtainable from the prior art by conventional processes can be obtained ,

The present invention was also based on the object of specifying a process for the preparation of a polyurethane based on polyisocyanates and polyether or polyester polyols, which is particularly suitable for producing kleinvo lumiger shaped body or small-volume sections containing moldings.

A contribution to the solution of the abovementioned objects is afforded by a process for producing a polyurethane comprising the process steps:

i) providing a polyisocyanate component comprising at least one polyisocyanate; ii) providing a polyol component comprising at least one polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, the polyol component comprising a polyol ester of a polyol and a monocarboxylic acid;

iii) contacting the polyisocyanate component with the polyol component to form a polyurethane.

In process step i) of the process according to the invention, first of all a polyisocyanate component containing at least one polyisocyanate is provided.

Suitable polyisocyanates are all polyisocyanates known to the person skilled in the art for the preparation of polyurethanes, which may optionally also be used as a mixture comprising at least two structurally different polyisocyanates. Aliphatic isocyanates, such as hexamethylene diisocyanate (HDI) or isophorone diisocyanate (IPDI), or preferably aromatic isocyanates, such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI) or mixtures of diphenylmethane diisocyanate and polymethylene polyphenylene polyisocyanates (crude MDI) may be used. It is also possible to use isocyanates which have been modified by the incorporation of urethane, uretdione, isocyanurate, allophanate, uretonimine and other groups, so-called modified isocyanates.

Furthermore, it is also possible to use polyisocyanate prepolymers as the polyisocyanate component. These prepolymers are known in the art. The preparation of such polyisocyanate prepolymers is carried out in a known manner by reacting polyisocyanates, for example, at tem- peratures of about 80 ⁰ C with, for example polyether polyols or polyester, but in particular with the below-described component to Po lyol-

- A - Be implemented prepolymer. The polyol-polyisocyanate ratio is generally chosen so that the NCO content of the prepolymer 8 to 25 wt -.%, Preferably 10 to 24 wt -.%, Particularly preferably 13 to 23 wt .-% is.

The polyisocyanate component may, if appropriate, in addition to the above-described polyisocyanate, also include one of the reactive components described in EP-A-0 477 638, for example one of the epoxy components described in this prior art, with regard to the nature of the epoxides, the amount in which they are used, as well as the manner of pretreatment of the polyisocyanate component with the epoxy component to the disclosure of EP-AO 477 638 is referenced.

In process step ii) of the process according to the invention, a polyol component comprising at least one polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol is provided, the polyol component comprising a polyol ester of a polyol and a monocarboxylic acid as viscosity reducer of the polyol Component includes.

The preparation of this polyol component is preferably carried out by mixing a polyetherpolyol component, a polyesterpolyol component or a mixture of a polyetherpolyol component and a polyesterpolyol component with the polyol ester. In this connection, it is particularly preferred that the polyether polyol component, the polyester polyol component or the mixture of the polyether polyol component and the polyester polyol component at least 50 wt .-%, more preferably at least 60 wt. %, moreover preferably at least 75% by weight, moreover still more preferably at least 95% by weight and most preferably at least 99% by weight, based in each case on the total weight of the polyether polyol component, of the polyester polyol Component or mixture of the polyether polyol component and the Polyesterpolyol component, based on a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol or consists of this.

In this context, it is furthermore particularly preferred according to the invention that the polyether polyol component used to prepare the polyol component is a highly viscous polyether polyol component, which preferably has a viscosity determined by Brookfield at 25 ° C. of at least 500 mPas, particularly preferably at least 1,000 mPas, and most preferably at least 2,000 mPas, wherein the Brookfield viscosity determined at 25 ° C is preferably in a range of 500 to 12,000 mPas, more preferably in a range of 1,000 to 10,000 mPas and most preferably in one range from 2,000 to 8,000 mPas. If a polyesterpolyol component is used to prepare the polyol component, it is particularly preferred according to the invention for the polyesterpolyol component used to prepare the polyol component to likewise be a high-viscosity polyesterpolyol component, which preferably has a Brookfield at 25 ° C has a certain viscosity of at least 1,000 mPas, more preferably of at least 2,000 mPas, and most preferably of at least 4,000 mPas, the viscosity determined according to Brookfield at 25 ° C preferably being in a range of from 1,000 to 20,000 mPas, more preferably in a range of 2,000 to 15,000 mPas, and most preferably in a range of 4,000 to 10,000 mPas

The polyether polyols contained in the polyol component or used for the preparation of this polyol component polyether polyol component are preferably obtainable by the reaction of an alkylene oxide with water, an amine, an amino alcohol or an alcohol starter molecule, wherein as alkylene oxide, for example, tetrahydrofuran, ethylene oxide , 1, 2-propylene oxide, 1,3-propylene oxide, 1,2- or 2,3-butylene oxide or styrene oxide can be used, particularly preferably 1, 2-propylene oxide or ethylene oxide. be set. The alkylene oxides can be used individually, alternately one after another or as mixtures. The use of an ethylene oxide / propylene oxide mixture leads, for example, to a polyether polyol having a statistical distribution of the ethylene oxide / propylene oxide units. However, it is also possible first to use an ethylene oxide / propylene oxide mixture and then only to use propylene oxide or ethylene oxide before termination of the polymerization in order to selectively obtain polyether polyols having a propylene oxide end cap or an ethylene oxide end cap. In this connection, it is particularly preferred that the alkylene oxide fraction, particularly preferably the ethylene oxide or propylene oxide fraction, is more than 50% by weight, based on 100% by weight of alkylene oxides and starter molecule.

In general, the polyether polyols are prepared by known processes, for example by anionic polymerization with alkali metal hydroxides, such as sodium or potassium hydroxide or alkali metal alkoxides, such as sodium methylate, sodium or potassium ethylate or potassium isopropoxide as catalysts and with addition of the starter molecule or by cationic polymerization with Lewis acids. Acids, such as antimony pentachloride, boron fluoride etherate u. a. or bleaching earth as catalysts prepared from one or more alkylene oxides, preferably from 1, 2-propylene oxide and ethylene oxide.

In the case of the use of an alcohol as a starter molecule for the preparation of the polyether polyol, it is preferred according to the invention that the alcohol is an alcohol having at least 2 hydroxyl groups in the molecule, preferably having 3 to 6 hydroxyl xylgruppen in the molecule. Particularly preferred dihydric alcohols in this context are ethylene glycol, propylene glycol or butanediols, while preferred trihydric alcohols include, for example, glycerol, trimethylolpropane or castor oil or pentaerythritol. Preferred higher-value alcohols are, in particular, sugar alcohols, for example sucrose, glucose or sorbitol. In the case of the use of an amine as a starter molecule for the preparation of the polyether polyol, it is erfmdungsgemäß preferred that the amine is an amine having at least two primary amino groups in the molecule. Examples of suitable aminic starter molecules are in particular amines selected from the group consisting of phenylenediamine, 2,3-toluenediamine, 2,4-toluenediamine, 3,4-toluenediamine, 2,6-toluenediamine, 4,4'-diaminodiphenylmethane, 2, 4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 1,2-ethylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, 1,6-hexylenediamine, 1,8-octylenediamine, diethylenetriamine and dipropylenetriamine.

If amino alcohols are used as the starter molecule, then in particular the use of monoethanolamine, diethanolamine or triethanolamine is used.

The polyether polyols used in the process according to the invention preferably have a functionality in a range from preferably 2 to 8, particularly preferably from 3 to 8. Furthermore, it is preferred according to the invention that the polyether polyols have hydroxyl numbers in a range from 10 mg KO H / g to 1200 mg KOH / g, more preferably in a range from 50 mg KO H / g to 800 mg KOH / g and moreover preferably in range from 100 mg KOH / g to 500 mg KOH / g.

Furthermore, the polyether polyols used in the process according to the invention are preferably by a number average molecular weight in a range of 100 to 10,000 g / mol, more preferably in a range of 200 to 5,000 g / mol, and most preferably in a range of 500 to 2,500 g / mol.

If appropriate, the polyether polyols used in the process according to the invention may also be further modified, for example by the catalytic addition of carbon dioxide and alkylene oxides to form polyisocyanates. ethercarbonatpolyolen, as described for example in WO-A-2008/058913.

Examples of suitable polyether polyols erfϊndungsgemäß or for the production-of Po lyol- component suitable poly etherpolyol- components are in particular the repeating is propylene oxide and / or ethylene oxide units constructed polyether polyols of Lupranol ^® brands from BASF AG. Further suitable homo-polyethylene oxides are for example the Pluriol® ^® E grades from BASF AG, while suitable homopolypropylene oxides include, for example Pluriol® ^® P grades from BASF AG. Suitable mixed co-polymers of ethylene oxide and propylene oxide are, for example Pluriol ^® PE or PLURIOL ^® RPE grades from BASF AG. Can be used, for example, the ^® under the Rokopol brands marketed products of the PCC Roki- ta SA, Poland.

The polyesterpolyols contained in the polyol component or the polyesterpolyol component used to prepare this polyol component are preferably obtainable by condensation of polyfunctional, preferably difunctional, alcohols having 2 to 12 carbon atoms, preferably 2 to 6 carbon atoms, with polyfunctional carboxylic acids From 2 to 12 carbon atoms, preferably with dicarboxylic acids.

Suitable dicarboxylic acids are, for example: succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid and the isomeric naphthalenedicarboxylic acids. Preferably, adipic acid is used. The dicarboxylic acids can be used both individually and in admixture with each other. Instead of the free dicarboxylic acids, it is also possible to use the corresponding dicarboxylic acid derivatives, for example dicarboxylic acid esters of alcohols having 1 to 4 carbon atoms or dicarboxylic acid anhydrides. Examples of dihydric and polyhydric alcohols, in particular diols, are: Ethanediol, diethylene glycol, 1,2- or 1,3-propanediol, dipropylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, glycerol and trimethylolpropane. Preferably used are ethanediol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol or mixtures of at least two of said diols, in particular mixtures of 1,4-butanediol, 1,5-pentanediol and 1, 6-hexanediol. It is also possible to use polyester polyols from lactones, for example ε-caprolactone or hydroxycarboxylic acids, for example ω-hydroxycaproic acid and hydroxybenzoic acids. Preferably used is dipropylene glycol.

Specific examples of suitable polyester polyols include in particular the Desmophen available from Bayer AG ^® polyesters, such as Desmophen ^® 650 MPA Desmophen ^® 651 MPA Desmophen ^® 670, Desmophen ^{® "670} BA and Desmophen ^® 680 X.

The hydroxyl number of the polyester alcohols is preferably in the range between 20 and 500 mg KOH / g, more preferably between 40 and 100 mg KOH / g.

It is now preferred according to the invention that the polyol component comprising the polyether polyol, the polyester polyol or the mixture of the polyether polyol and the polyester polyol includes a polyol ester of a polyol and a monocarboxylic acid. It has surprisingly been found that, in particular, polyol esters of short-chain monocarboxylic acids can be used as viscosity reducers for highly viscous polyether polyols without these polyesters having an adverse effect on polyurethane formation. According to the process of the invention, therefore, the preferably highly viscous polyether polyol component used, preferably the highly viscous polyesterpolyol component or the preferably highly viscous mixture of the polyether polyol component and the polyesterpolyol component, is first brought into contact with the polyol ester, preferably by simple mixing. to reduce the viscosity of this polyol component. Only then will the tene polyol component with the other components (polyisocyanate component and optionally other compounds having at least two isocyanate-reactive hydrogen atoms and optionally further additives) brought to form the polyurethane in contact. It is also conceivable, however, to add further additives, in particular fillers, to the polyol component, and to mix the thus-obtained even more viscous polyol component with the polyol ester.

According to a preferred embodiment of the process according to the invention, the polyol component comprises the polyol ester in an amount in a range of 0.1 to 30% by weight, more preferably in a range of 1 to 20% by weight and most preferably in one Range of 5 to 15 wt .-%, each based on the total weight of the polyol component.

The polyol ester preferably used as a viscosity reducer in the process according to the invention is preferably obtainable by reacting a monocarboxylic acid or a monocarboxylic acid derivative with a polyol. The term "dicarboxylic acid derivative" encompasses all derivatives of a monocarboxylic acid which, in a reaction with a polyol, lead to a corresponding poly-ol ester of the monocarboxylic acid, In particular, the term "monocarboxylic acid derivative" includes the acid chlorides of the monocarboxylic acid and the acid anhydrides of the monocarboxylic acid. These derivatives preferably have an increased reactivity of the carboxylic acid group in comparison with the monocarboxylic acid, so that ester formation is favored on reaction with a polyol.

The polyol used to prepare the polyol ester is preferably a polyol having 2 to 6 OH groups, which may be selected, for example, from the group consisting of ethylene glycol, propylene glycol, trimethylolpropane, glycerol, pentaerythritol, sorbitol and dipentaerythritol, the use of glycerol being particularly preferred. When producing the Polyester used monocarboxylic acid is preferably a Ci to Cs monocarboxylic acid, or a derivative of a Ci to Cs monocarboxylic acid, for example an acid chloride or an acid anhydride of a C to C monocarboxylic acid, more preferably a C ₂ bis C ₄ monocarboxylic acid or a derivative of a C ₂ to C ₄ monocarboxylic acid, for example an acid chloride or an acid anhydride of a C ₂ to C ₄ monocarboxylic acid. As examples of suitable monocarboxylic acids, particular preference is given to monocarboxylic acids selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid and 2-ethylhexanoic acid, the use of acetic acid or a derivative thereof or propionic acid or a derivative thereof being particularly preferred. Particularly preferred according to the invention is the use of glycerol triacetate as the polyol ester.

The preparation of a polyol ester from a polyol and a monocarboxylic acid or from a polyol and a derivative of a monocarboxylic acid by an esterification reaction is well known to the person skilled in the art. Preferably, the monocarboxylic acid or the derivative of the monocarboxylic acid is reacted with the polyol in such an amount that all OH group are esterified to the polyol. However, it is also conceivable to use the monocarboxylic acid in such an amount that only a part of the OH groups of the polyol is esterified.

According to a preferred embodiment of the process according to the invention, this can comprise the further process step iv) of providing further compounds having at least two isocyanate-reactive hydrogen atoms, this process step iv) being carried out before process step iii). As further compounds having at least two isocyanate-reactive hydrogen atoms it is possible in principle to use all compounds known in connection with the preparation of polyurethanes having at least two hydrogen atoms reactive with isocyanate groups. Particularly suitable here are low-viscosity polyester polyols or optionally low-viscosity polyether polyols, these being low-viscosity Polyether or polyester polyols preferably have a Brookfield viscosity at 25 ° C of less than 500 mPas, more preferably less than 250 mPas, even more preferably less than 100 mPas and more preferably less than 50 mPas.

According to a further preferred embodiment of the process according to the invention, this process can also comprise the further process step v) of providing further components of various additives provided by the process steps i), ii) and optionally iv), wherein this process step v) also precedes the process step iii ) is carried out. In this case, all additives known to the person skilled in the art for the preparation of polyurethanes can be used as further additives. These further additives may in particular comprise chain extenders and / or crosslinking agents, catalysts, mold release agents, plasticizers, pore regulators, fungistatic and bacteriostatic substances, dyes, pigments, blowing agents, stabilizers, fillers or flame retardants. The amount of additives is preferably less than 25% by weight, more preferably less than 20% by weight, most preferably less than 15% by weight, based in each case on the total weight of the process steps i), ii) and optionally iv) and / or v) provided components. If fillers are used as further additives, the amount of the further additives can also be significantly higher and under certain circumstances up to 70% by weight, based on the total weight of the process steps i), ii) and optionally iv) and / or v ) provided components.

As chain extenders and / or crosslinking agents are usually used diols and / or Trio Ie having molecular weights less than 400 g / mol, preferably with molecular weights in the range of 60 to 300 g / mol. Suitable examples include aliphatic, cycloaliphatic and / or araliphatic diols having 2 to 14, preferably 4 to 10 carbon atoms, such as ethylene glycol, 1,3-propanediol, 1,10-decanediol, o-, m-, p-dihydroxycyclohexane , Diethylene glycol, dipropylene glycol and preferably 1,4-butanediol, 1,6- Hexanediol and bis (2-hydroxyethyl) hydroquinone, trio Ie, such as 1,2,4- and 1,3,5-trihydroxycyclohexane, triethanolamine, diethanolamine, glycerol and trimethylolpropane.

Catalysts are used, for example, in the production of rigid polyurethane foams to promote the incorporation of isocyanurate groups. The isocyanurate catalysts used are usually metal carboxylates, in particular potassium acetate and its solutions. Other catalysts useful in the preparation of polyurethanes are the activators known in the art, such as tertiary amines, tin or titanium compounds.

Blowing agents are used when polyurethane foams are to be produced. The propellant used is preferably a propellant containing formic acid. This can be used as the sole blowing agent or in admixture with water and / or physical blowing agents. Preferably used as physical blowing agents are hydrocarbons, halogenated hydrocarbons such as chlorofluorocarbons (FCCs), hydrogen fluorochlorohydrocarbons (HFCCs) or hydrofluorocarbons (HFCs) and other compounds such as perfluorinated alkanes such as perfluorohexane as well as ethers, esters, ketones and acetals, or mixtures thereof , Particularly preferred are hydrogen fluorocarbons, such as 1,1,1,3,3-pentafluorobutane, 1,1,1,3,3-pentafluoropropane, 1,1,1,2-tetrafluoroethane or 1,1,1,2 , 3,3,3-heptafluoropropane and mixtures thereof. Preference is furthermore given to using hydrocarbons, such as, for example, the isomers and derivatives of pentane, as physical blowing agents.

Suitable stabilizers are, in particular, foam stabilizers, antioxidants, UV stabilizers or hydrolysis stabilizers. The selection of these stabilizers depends, on the one hand, on the main components of the composition and, on the other, on the conditions of use and on the other expected loads of polyurethane. When the polyurethane in the backbone is made up of polyether building blocks, it is mainly antioxidants, if necessary in combination with UV protectants, that are necessary. Examples of these are the commercially available, sterically hindered phenols and / or thioethers and / or substituted benzotriazoles or the sterically hindered amines of the HALS type ("J-found Amine Light Stabilizer"). If essential constituents of the main chain of the polyurethane are polyester building blocks, they are preferably Hydrolysis stabilizers, for example of the carbodiimide type used.

As stabilizers surface-active substances, d. H. Compounds are used which serve to assist the homogenization of the starting materials and may also be suitable for regulating the cell structure of the polyurethanes. Mention may be made, for example, of emulsifiers, such as the sodium salts of castor oil sulfates or fatty acids and salts of fatty acids with amines.

Foam stabilizers are substances which promote the formation of a regular cell structure during foaming. Examples of suitable foam stabilizers are in particular silicone-containing foam stabilizers, such as siloxane-oxalkylene copolymers and other organopolysiloxanes. Also, alkoxylation of fatty alcohols, oxoalcohols, fatty amines, alkylphenols, dialkylphenols, alkylcresols, alkylresorcinol, naphthol, alkylnaphthol, naphthylamine, aniline, alkylaniline, To luidin, bisphenol A, alkylated bisphenol A, polyvinyl alcohol, and further alkoxylation of condensation products of formaldehyde and alkylphenols, formaldehyde and dialkylphenols, formaldehyde and alkylcresols, formaldehyde and alkylresorcinol, formaldehyde and aniline, formaldehyde and toluidine, formaldehyde and naphthol, formaldehyde and alkylnaphthol, and formaldehyde and bisphenol A or mixtures of two or more thereof can be used as foam stabilizers. As flame retardants, the flame retardants known from the prior art can generally be used. Suitable flame retardants are, for example, brominated ethers, brominated alcohols, such as dibromoneopentyl alcohol, tribromoneopentyl alcohol and PHT-4-diol, and also chlorinated phosphates, such as tris (2-chloroethyl) phosphate, tris (2-chloroisopropyl) phosphate (TCPP). , Tris (1,3-dichloroisopropyl) phosphate, tris (2,3-dibromopropyl) phosphate and tetrakis (2-chloroethyl) ethylenediphosphate, or mixtures thereof. In addition to the abovementioned halogen-substituted phosphates, it is also possible to use inorganic flameproofing agents such as red phosphorus, red phosphorus-containing finishes, expandable graphite (expandable graphite), aluminum oxide hydrate, antimony trioxide, arsenic oxide, ammonium polyphosphate and calcium sulfate or cyanuric acid derivatives such as melamine or mixtures of at least two flame retardants, such as ammonium polyphosphates and melamine and optionally starch, are used for flameproofing the polyurethanes produced according to the invention.

As mold release agents, it is possible, for example, to use those mold release agents which are described in DE-A1 953 637, DE-A-2 121 670, DE-A-2 431 968 or DE-A-24 04 310. Preferred release agents are the salts of fatty acids having at least 12 aliphatic carbon atoms and containing at least 12 aliphatic carbon atoms and primary mono-, di- or polyamines having two or more carbon atoms or amides or amides having at least one primary, secondary or tertiary amino group. saturated and / or unsaturated COOH- and / or OH-containing esters of mono- and / or polyfunctional carboxylic acids and polyfunctional alcohols having hydroxyl or acid numbers of at least 5, ester-type reaction products of ricinoleic acid and long-chain fatty acids, salts of carboxylic acids and tertiary Amines and natural and / or synthetic oils, fats or waxes. In addition to these separating agents which are mentioned by way of example and which are to be used with preference, in principle other known separating agents of the prior art can be used alone or in admixture with the preferred release agents known per se in the process according to the invention. These further suitable release agents include, for example, the reaction products of fatty acid esters and polyisocyanates according to DE-A-23 07589, the reaction products of reactive hydrogen atoms containing polysiloxanes with mono- and / or polyisocyanates according to DE-A-23 56 692, esters of hydroxides. Polysiloxanes containing xymethyl groups with mono- and / or polycarboxylic acids according to DE-A-23 63 452 and salts of polysiloxanes containing amino groups and fatty acids according to DE-A-24 27 273 or DE-A-24 31 968.

Examples of suitable fillers, in particular reinforcing fillers, are silicate minerals, for example sheet silicates such as antigorite, serpentine, hornblende, amphiboles, chrysotile, talc, metal oxides such as kaolin, aluminas, titanium oxides and iron oxides, metal salts such as chalk, barite and inorganic pigments. such as phthalocyanine complex as well as glass flour called.

In process step iii) of the process according to the invention, the polyisocyanate component with the polyol component, if appropriate in the presence of the further additives provided in process step v) and optionally the further compounds provided in process step iv) having at least two isocyanate-reactive Hydrogen atoms brought into contact with forming a polyurethane, wherein bringing this into contact preferably by intimately mixing the in process steps i), ii), optionally iv) and optionally v) provided components. Furthermore, it is preferred that the mixing of the components provided in process steps i), ii), optionally iv) and optionally v) takes place at a temperature of less than 60 ^° C., more preferably of less than 40 ^° C. The exact manner of contacting the individual components provided in process steps i), ii), optionally iv) and optionally v) is not critical to the inventive process (with the exception that the conditions for the preparation of the polyol) Component used polyetherpolyol- component, polyesterpolyol- component or mixture of the polyetherpolyol- component and the polyesterpolyol- component is first mixed with the polyol ester for the purpose of reducing the viscosity of the polyol component) and depends in particular on it whether a foamed or a non-foamed polyurethane is to be produced. An overview of the processes used for the preparation of polyurethanes can be found, for example, in the Kunststoffhandbuch, Volume 7, Polyurethane ", Carl Hanser Verlag, Munich, Vienna, 1st Edition 1966, 2nd Edition 1983 and 3rd Edition 1993. Basically however, contacting the components may be continuous or discontinuous, by the one-shot method, or by the prepolymer method using known mixing devices.

In the industrial production of polyurethane foams, it is customary to combine the polyol component, the further additives and optionally the further compounds with at least two isocyanate-reactive hydrogen atoms before the reaction and then mix the resulting mixture with the polyisocyanate component in which case all mixing devices known to the person skilled in the art can be used. The precise proportions in which in particular the polyol component and optionally the further compounds having at least two isocyanate-reactive hydrogen atoms are reacted with the polyisocyanate component, depends on the properties which the intended polyurethane should have. Usually, however, the polyisocyanate component and the polyol component or the mixture of the polyol component and the further compounds are combined with at least two isocyanate-reactive hydrogen atoms in an amount such that the isocyanate index between In the context of the present invention, the isocyanate index is understood as meaning the stoichiometric ratio of isocyanate groups to isocyanate-reactive hydrogen atoms multiplied by 100.

However, according to a particularly preferred embodiment of the method according to the invention, method step iii) is carried out as a reaction injection molding method. In such a process, it is preferred that the polyisocyanate component and the polyol component and optionally the other components provided in process steps iv) and / or v) are metered into a mixing chamber (it is also conceivable that individual components, in particular the components provided in process steps ii), iv) and v), are mixed with one another before being fed into the mixing chamber, are mixed in the mixing chamber to give a polyurethane reaction mixture and the polyurethane reaction mixture is subsequently passed through a Sprue channel is discharged into the cavity of a mold. Such a method is described for example in DE-A-10 2004 006 074.

In this context, it may prove particularly advantageous that the discharge of the polyurethane reaction mixture into the cavity at a pressure of less than 5 bar, more preferably less than 4 bar, more preferably less than 2 bar, moreover more preferably less than 1 bar, and most preferably at atmospheric pressure.

Because of the comparatively low viscosity of the reaction mixture obtained in step iii) by contacting the components provided in process steps i), ii), optionally iv) and optionally v), it can also be used in cavities with a small total volume or in cavities. which comprise defined sections with a small section volume. In this connection, it is particularly preferred that the cavity has a total volume of less than 15 cm ³ , more preferably less than 10 cm, and most preferably less than 5 cm. A contribution to the solution of the abovementioned objects is also made by a polyurethane which is obtainable by the process described above. This polyurethane is preferably a polyurethane molding.

A further contribution to the solution of the abovementioned objects is afforded by a polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, comprising a polyol ester of a polyol and a monocarboxylic acid as viscosity reducer, where Polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol and as polyol esters those components or compounds are preferred which already in the context of the erfmdungsgemäßen method for producing a polyurethane as a preferred component or as preferred polyether or polyester polyols or polyol esters were called. According to a particular embodiment of the polyol component according to the invention, this contains the polyol ester in an amount in a range from 0.1 to 30% by weight, more preferably in a range from 1 to 20% by weight and most preferably in one range from 5 to 15 wt .-%, each based on the total weight of the polyol component.

A further contribution to the solution of the abovementioned objects is also provided by a process for the preparation of a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol-containing polyol component, in which a polyether polyol component, a polyester polyol component or a mixture of a polyether polyol component and a polyester polyol component with a polyol ester of a polyol and a monocarboxylic acid is preferably brought into contact by mixing. Again, as a polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a Polyesterpolyol_und preferred as polyol esters are those components or compounds which have already been mentioned at the outset in connection with the process according to the invention for preparing a polyurethane as preferred polyether or polyester polyols or as polyol esters. According to a particular embodiment of the process according to the invention for producing a polyol component, the polyether polyol component used is a highly viscous polyether polyol component which preferably has a Brookfield viscosity of at least 500 mPas, more preferably at least 1,000 mPas, determined at 25 ° C. most preferably at least 2,000 mPas, wherein the Brookfield viscosity at 25 ° C is preferably in the range of 500 to 12,000 mPas, more preferably in the range of 1,000 to 10,000 mPas, and most preferably in the range of 2,000 to 8,000 mPas. If a polyesterpolyol component is used, the polyesterpolyol component used is preferably a high-viscosity polyester polyol component having a Brookfield viscosity at 25 ° C. of at least 1,000 mPas, more preferably at least 2,000 mPas, and most preferably of at least 4,000 mPas, wherein the Brookfield viscosity at 25 ° C is preferably in the range of 1,000 to 20,000 mPas, more preferably in the range of 2,000 to 15,000 mPas, and most preferably in the range of 4,000 to 10,000 mPas lies.

It is also preferred that the polyether polyol component, the polyester polyol component or the mixture of the polyether polyol component and the polyester polyol component at least 50 wt .-%, more preferably at least 60 wt .-%, more preferably at least 75% by weight, more preferably at least 95% by weight, and most preferably at least 99% by weight, based in each case on the total weight of the polyether polyol component, of the polyester polyol component or the mixture of the polyether polyol component and the polyester polyol component, on a polyether polyol, a polyester polyol or a is based on a polyether polyol and a polyester polyol or consists of this.

Furthermore, in connection with the process according to the invention for the preparation of a polyol component, it is preferred that the polyol ester with the polyether polyol component, the polyester polyol component or the mixture of the polyether polyol component and the polyester polyol component be present in an amount in one From 0.1 to 30% by weight, more preferably from 1 to 20% by weight, and most preferably from 5 to 15% by weight, based in each case on the total weight of polyether polyol used. Component, polyesterpolyol used component or used mixture of Po Iy etherpo Iy component and polyester polyol component and used polyol ester is brought into contact.

A contribution to the solution of the abovementioned objects is further provided by a polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, which is obtainable by the process described above. In addition, the use of the inventive polyol component or the polyol component obtainable by the inventive method for producing a polyol component in a process for the preparation of a polyurethane, preferably in a reaction injection molding process such as it was described at the beginning.

Another contribution to the solution of the abovementioned objects is the use of a polyol ester of a polyol and a monocarboxylic acid as viscosity reducer for a polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, where also here as polyol ester, as a polyether polyol, as a polyester polyol and as a polyol component those compounds or Ko m- Preference is given to components which have already been mentioned as preferred compounds or components in connection with the process according to the invention for preparing a polyurethane.

The invention will now be explained in more detail by way of non-limiting examples.

EXAMPLES

example 1

Preparation of a polyol component of the invention based on a polyether polyol

90 g of a polyether polyol of sorbitol and ethylene oxide / propylene oxide (available from PCC Rokita SA, Poland, under the trade designation rococo pol ^® 551 (viscosity: 3,600 mPas is) available with 10 wt .-% glycerol (by Cognis Oleochemicals GmbH, Germany) The viscosity of the polyol component thus obtained was 1,640 mPas.

Example 2

Preparation of a further, inventive polyol component

90 g of a polyether polyol of sorbitol and ethylene oxide / propylene oxide (available from PCC Rokita SA, Poland, under the trade designation rococo pol ^® 551 (viscosity: 3,600 mPas) is mixed with 10 wt .-% glycerol tripropionate The viscosity of the so obtained. Polyol component was 1450 mPas.

Example 3

Preparation of a polyurethane On the basis of Po obtained in Examples 1 and 2 lyol- component and, as a comparative example, on the basis of the non-offset with a polyol ester Rokopol ^® 551 -Produktes a polyurethane was prepared. The following components were produced

A component:

92.0 parts by weight of polyol component of Example 1 or 2 or pure Rokopol ^® 551 -product,

0.15 parts by weight of triethanolamine; 6 parts by weight of 1,4-butanediol; 1.8 parts by weight of DABCO (1,4-diazabicyclo [2.2.2] octane); 0.05 parts by weight of dibutyltin laurate.

Component B:

33 parts by weight 4,4'-diphenylethane diisocyanate reacted with tripropylene glycol with an NCO content of 23%.

The two components A and B were mixed together at a ratio of 121 and then foamed. That the component was mixed with the A obtained in Examples 1 and 2, polyol component significantly better with the component B as a component A which 551 -product was produced by a pure Rokopol ^® thereby revealed.

Example 4

Preparation of an inventive Po lyol component based on a polyester polyol The polyester polyol Edenol ^® 1230 (viscosity: 3,840 mPas) were added to 10 wt .-% glycerol. The viscosity of the resulting Po lyol component was 2317 mPas.

Also with this polyol component was prepared according to Example 3, a polyurethane. Here, too, it was found that a component A, which comprises the glycerol triacetate offset Edenol ^® 1230 -product contains significantly better was mixed with the component B as the corresponding component A with the pure Edenol ^® 1230 -product.

Claims

claims

1. A process for producing a polyurethane, comprising the steps of: i) providing a polyisocyanate component containing at least one polyisocyanate; ii) providing a polyol component comprising at least one polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, wherein the

Polyol component of a polyol ester of a polyol and a

Monocarboxylic acid includes; iii) contacting the polyisocyanate component with the polyol component to form a polyurethane.

2. The method of claim 1, wherein the step iii) is carried out as a reaction injection molding.

3. The method of claim 2, wherein the polyisocyanate component and the polyol component are metered into a mixing chamber, are mixed in the mixing chamber to a polyurethane reaction mixture and then discharged the polyurethane reaction mixture via a runner into the cavity of a mold becomes.

4. The method of claim 3, wherein the discharging of the polyurethane

Reaction mixture into the cavity at a pressure of less than 5 bar.

The method of claim 3, wherein the cavity has a volume of less than 15 cm ³ .

6. The method according to any one of the preceding claims, wherein the

Polyether polyol is obtainable by reacting an alkylene oxide with water, an amine, an amino alcohol or an alcohol.

The process of claim 6, wherein the alkylene oxide is ethylene oxide or propylene oxide.

8. The method of claim 7, wherein the alcohol is an alcohol having at least 3 hydroxyl groups in the molecule.

The method of claim 8, wherein the alcohol is selected from the group consisting of trimethylolpropane, glycerol, pentaerythritol, and sugar compounds.

The process of claim 6, wherein the amine is an amine having at least two primary amino groups in the molecule.

11. The process according to claim 10, wherein the amine is selected from the group consisting of phenylenediamine, 2,3-toluenediamine, 2,4-toluenediamine, 3,4-toluenediamine, 2,6-toluenediamine, 4,4'-

Diaminodiphenylmethane, 2,4'-diaminodiphenylmethane, 2,2'-

Diaminodiphenylmethane, 1,2-ethylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, 1,6-hexylenediamine, 1,8-octylenediamine, diethylenetriamine and dipropylenetriamine.

12. The method according to any one of the preceding claims, wherein the polyether polyol has a functionality of preferably 3 to 8.

The process of any one of the preceding claims, wherein the polyether polyol has a hydroxyl number in the range of 50 mg KOH / g to 1200 mg KOH / g.

14. The method according to any one of the preceding claims, wherein the polyester polyol is obtainable by condensation of polyhydric alcohols with polyfunctional carboxylic acids.

The method of claim 14, wherein the polyhydric alcohol is a diol having 2 to 12 carbon atoms.

The process of claim 14 or 15, wherein the polyfunctional carboxylic acid is a polyfunctional carboxylic acid having 2 to 12 carbon atoms.

17. The process according to any of claims 14 to 16, wherein the polyester polyol has a hydroxyl value in a range of 50 mg KOH / g to 1200 mg KOH / g and the polyester polyol has a hydroxyl number in one

Range from 20 mg KOH / g to 500 mg KOH / g.

18. The process according to any of the preceding claims, wherein the polyol component is obtainable by mixing a polyether polyol component, a polyester polyol component or a mixture of a polyether polyol component and a polyester polyol component with the polyol ester.

19. The process of claim 18, wherein the polyether polyol component has a Brookfield viscosity at 25 ° C of at least 500 mPas.

20. The process of claim 18 wherein the polyester polyol component has a Brookfield viscosity at 25 ° C of at least 1,000 mPas.

21. The process of any one of the preceding claims, wherein the polyol component includes the polyol ester in an amount in the range of 0.1 to 30 weight percent, based on the total weight of the polyol component.

22. The process of claim 21, wherein the polyol component includes the polyol ester in an amount in the range of 5 to 15 weight percent, based on the total weight of the polyol component.

23. The method according to any one of the preceding claims, wherein the polyol used to prepare the polyol ester is a polyol having 2 to 6 OH groups.

24. The process of claim 23 wherein the polyol used to make the polyol ester is a polyol selected from the group consisting of ethylene glycol, propylene glycol, trimethylolpropane, glycerine, pentaerythritol, sorbitol, and dipentaerythritol.

25. The method according to any one of the preceding claims, wherein the monocarboxylic acid used for the preparation of the polyol ester a ci- to

C8 monocarboxylic acid is.

26. The process of claim 25, wherein the monocarboxylic acid is selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid and 2-ethylhexanoic acid.

The method of any one of the preceding claims, wherein the polyol ester is glycerol triacetate or glycerol tripropionate.

A polyurethane obtainable by the process of any one of claims 1 to 27.

29. A polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, comprising a polyol ester of a polyol and a monocarboxylic acid.

30. A process for producing a polyol component comprising a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol, in which a polyether polyol component, a polyester polyol component or a polyester polyol component

Blend of a polyether polyol component and a polyester polyol component with a polyol ester of a polyol and a monocarboxylic acid is mixed.

31. A polyol component comprising a polyether polyol, a polyester polyol, or a blend of a polyether polyol and a polyester polyol, obtainable by the process of claim 30.

32. Use of the polyol component according to claim 29 or 31 as compounds having at least two isocyanate-reactive hydrogen atoms in a process for the preparation of a polyurethane.

33. Use of a polyol ester of a polyol and a monocarboxylic acid as viscosity reducer for a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a

Polyester polyol-containing polyol component.