EP2643373A1

EP2643373A1 - Method for producing flexible polyurethane foams

Info

Publication number: EP2643373A1
Application number: EP11788418.9A
Authority: EP
Inventors: Hartmut Nefzger; Erika Bauer; Bert Klesczewski; Jürgen SCHLOSSMACHER; Sven Meyer-Ahrens; Manfred Schmidt
Original assignee: Bayer Intellectual Property GmbH
Current assignee: Bayer Intellectual Property GmbH
Priority date: 2010-11-22
Filing date: 2011-11-18
Publication date: 2013-10-02
Also published as: US20130345330A1; WO2012069386A1; CN103328521A

Abstract

The invention relates to a method for producing polyricinoleic acid esters, comprising the step of reacting ricinoleic acid with an alcohol component which comprises monohydric and/or polyhydric alcohols having a molecular mass of ≥ 32 g/mol to ≤ 400 g/mol, wherein the reaction is carried out in the presence of a catalyst, at least in part. The catalyst quantity, relative to the total mass of ricinoleic acid and the alcohol component, ranges between ≥ 10 ppm and ≤ 100 ppm. The reaction is terminated when the acid number of the obtained reaction product has reached ≥ 5 mg KOH/g to ≤ 100 mg KOH/g. The invention further relates to a polyurethane polymer, in particular a flexible polyurethane foam, which can be obtained using said polyricinoleic acid esters.

Description

Process for the production of flexible polyurethane foams

The present invention relates to a process for the preparation of Polyricinolsäureestem, comprising the step of the reaction of ricinoleic acid with an alcohol component comprising monohydric and / or polyhydric alcohols having a molecular weight of> 32 g / mol to <400 g / mol and wherein the reaction at least partially carried out in the presence of a catalyst. It also relates to polyurethane polymers prepared with these Polyricinolsäureestem, especially flexible polyurethane foams. Polyricinolsäureester be technically obtained by polycondensation of ricinoleic acid. This reaction proceeds slowly compared to the esterification of, for example, adipic acid and di-primary hydroxyl components and is therefore economically disadvantageous. To balance the material-related minor functionality of hydroxyl groups, a low molecular weight polyol can be added as a further component in the synthesis of Polyricinolsäureester to ultimately ensure the excess of hydroxyl over the carboxyl groups.

At present, on an industrial scale, in the synthesis of a polyricinolate of ricinoleic acid and a low molecular weight polyol, boiler times of sometimes more than 80 hours are required to produce a product having an acid number of, for example, in the range of 5 mg KOH / g and a hydroxyl number in the range of 40 mg KOH / g to obtain.

A preparation of Polyricinolsäureestem is described for example in EP 0 180 749 AI. This patent application relates to a process for the preparation of optionally microcellular, elastomeric moldings with self-supporting properties. This is done in closed molds in a reaction mixture with dry polyisocyanates and solutions of chain extenders of the molecular weight range from 62 to 400 in relatively high molecular weight polyhydroxyl compounds in the molecular weight range from 1800 to 12,000 implemented with the assistance of catalysts, internal mold release agents and optionally other auxiliaries and additives.

Inner mold release agents discussed herein are ester grouped condensation products having a molecular weight range of 900-4500, an acid number less than 5, and a hydroxyl number of 12.5-125 of 3 to 15 moles of ricinoleic acid and one mole of a mono- or polyhydric alcohol in the 32 to 32 molecular weight range 400 or a total of one mole of a mixture several such alcohols. These Polyncinolsäureester be referred to as essential to the invention.

For economic reasons, it would be advantageous to bring the reaction times and thus the production costs for the synthesis of Polyricinolsäureestern to less than about 30 hours. This is a typical area for other polyesters. To be able to actually use the advantage of shorter reaction times, such Polyricinolsäureester should be usable especially in existing polyurethane Weichschaumre zepturen without we sentliche change the recipe al s polyol component. The foams produced therefrom should also be comparable in their properties to conventional foams.

Surprisingly, it has been found that the aforementioned objects are achieved by a process for the preparation of polyricinoleic acid esters, comprising the step of the reaction of ricinoleic acid with an alcohol component, which monohydric and / or polyhydric alcohols having a molecular weight of> 32 g / mol to <400 g / mol and wherein the reaction is carried out at least partially in the presence of a catalyst.

The inventive method is characterized in that the amount of the catalyst, based on the total mass of the ricinoleic acid and the alcohol component, in a range of> 10 ppm to <100 ppm and that the reaction is terminated when the acid number of the resulting reaction product > 5 mg KOH / g to <50 mg KOH / g.

Suitable monohydric or polyhydric alcohols may include, but are not limited to, alkanols, cycloalkanols and / or polyether alcohols. Examples are n-hexanol, n-dodecanol, n-octadecanol, cyclohexanol, 1,4-dihydroxycyclohexane, 1,2-propanediol, 1,3-propanediol, 2-methylpropanediol-1,3, 1,4-butanediol, 1, 5-pentanediol, 1,6-hexanediol, 1, 8-octanediol, neopentyl glycol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, dibutylene glycol, tripropylene glycol, glycerol and / or trimethylolpropane.

Suitable catalysts or catalyst precursors can Lewis or Brönstedt acids such as sulfuric acid, p-toluenesulfonic acid, tin (II) salts or titanium (IV) - compounds such as titanium tetrabutoxide or titanium (IV) alcoholates. For the calculation of the catalyst content is assumed in the case of Brönstedt acids of the neutral compound. For example, sulfuric acid is based on the molecule H2SO4. If the catalyst is a Lewis acid, the catalytically active cationic species is used. For example, in the case of stannous salts, only the Sn ²⁺ cation would be considered regardless of the particular counterion, or only the Ti ⁴⁺ cation in the case of titanium (IV) compounds. This approach is advantageous because the content of metallic species can be determined by atomic absorption (AAS) spectroscopy without having to know the respective counterion. The proportion of the catalyst may, based on the total mass of the ricinoleic acid and the alcohol component, also in a range of> 20 ppm to <80 ppm, preferably from> 40 ppm to <60 ppm.

The reaction can be carried out at reduced pressure and elevated temperature while simultaneously distilling off the water formed during the condensation reaction. It can also be carried out by the azeotrope process in the presence of an organic solvent such as toluene as entrainer or by the carrier gas method, ie by expelling the resulting water with an inert gas such as nitrogen or carbon dioxide. According to the invention, it is provided that the reaction is terminated when the acid number of the reaction product obtained is> 5 mg KOH / g to <50 mg KOH / g. This value can be determined according to DIN 53402 and determined during the reaction, for example by sampling. This acid number may preferably also be in a range from> 5.2 mg KOH / g to <20 mg KOH / g or from> 5.4 mg KOH / g to <10 mg KOH / g. The termination of the reaction can in the simplest case by cooling the reaction mixture, for example, to a temperature <50 ° C, take place.

It has been found that the polyricinoleic acid esters (component A2) prepared according to the invention in a shorter reaction time than the prior art can nevertheless advantageously be used with their comparatively high acid number and amount of catalyst to prepare polyurethanes.

The molar ratio of ricinoleic acid and the alcohol component is preferably in a range of> 3: 1 to <10: 1. Particularly preferably, this ratio is> 4: 1 to <8: 1 and more preferably> 5: 1 to <7: 1 , Surprisingly, it has been found that the Polyricinolsäureester obtained by the process according to the invention can be incorporated into flexible foam formulations, without the formulations, which were originally based on purely synthetic components of the polyol components, by the concomitant use of a natural product based ingredient (Polyricinolsäureester) fundamentally To change, ie the processability and mechanical properties are at a comparable level.

The process according to the invention preferably comprises the alcohol component 1,4-dihydroxycyclohexane, 1,2-propanediol, 1,3-propanediol, 2-methylpropanediol-1,3,3,4-butanediol, 1,5-pentanediol, 1,6-hexanediol , Neopentyl glycol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, cyclohexanedimethanol, glycerol and / or trimethylolpropane. Particular preference is given here to 1,3-propanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, and / or trimethylolpropane. The alcohols mentioned have boiling points at which a discharge can be avoided together with water of reaction and tend at the usual reaction temperatures also not to undesirable side reactions.

The process preferably comprises as catalyst tin (II) salts. Particularly preferred here is tin (II) chloride. It has been found that tin (II) salts in a subsequent reaction of Polyricinolsäureesters not to interfere with polyurethanes or can also be advantageously used as a catalyst in this subsequent reaction.

In the process according to the invention, the reaction time is preferably from> 10 hours to <30 hours. The reaction time is more preferably> 12 hours to <25 hours and more preferably> 15 hours to <20 hours.

The reaction temperature of the process is preferably> 150 ° C to <250 ° C. The temperature may also range from> 180 ° C to <230 ° C, and more preferably> 190 ° C to <210 ° C. These temperature ranges represent a good balance between the desired reaction rate and possible undesired side reactions such as the elimination of water at the OH group of ricinoleic acid.

In a preferred embodiment of the process, firstly ricinoleic acid and the alcohol component are reacted without a catalyst. The catalyst is then added when the water-forming reaction has stopped. Subsequently, the Reaction catalyzes further carried out. The fact that the reaction initially proceeds without catalyst means that no additional external catalyst is used. This remains unaffected catalysis by the constituents of the reaction mixture polyricinoleic acid and monohydric or polyhydric alcohols themselves.

The formation of water is deemed to have come to a standstill if, after optical control of the reaction, no more water distils off or if more than 95% of the theoretical amount of water was removed from the reaction. This can be determined for example by a suitably equipped distillation template, a Dean-Stark apparatus or by weight control of the distillate formed. To determine the end of the formation of water, it is also possible, for example, to spectroscopically monitor the absorption behavior of COOH and / or OH groups in the NIR range. Then the reaction can be completed up to previously determined absorbance values. The fact that the reaction continues to be catalyzed after the addition of the catalyst means, in this connection, the catalysis due to the addition of an external catalyst.

According to this embodiment, a catalyst susceptible to hydrolysis, for example titanium (IV) alcoholates, can be used only at a late point in time at which at least the majority of the water of reaction has already been separated off. As a result, the reaction time is not adversely affected since the esterification reaction in the initial stage is autocatalyzed by the free COOH groups of Ricinolsäureeinheiten and catalyst is introduced only when the reaction mixture begins to deplete of COOH groups. The present invention furthermore relates to a polyricinoleic acid ester obtainable by a process according to the invention. It is characterized by an acid number of> 5 mg KOH / g to <50 mg KOH / g and a catalyst content of> 10 ppm to <100 ppm. The acid number can be determined according to DIN 53402. Catalysts or catalyst precursors which remain in the Polyricinolsäureester after its preparation, Lewis or Bronsted acids such as sulfuric acid, p-toluenesulfonic acid, tin (II) salts or titanium (IV) compounds such as titanium tetrabutoxide or titanium (IV) can be alcoholates , Preference is given to tin (II) salts, in particular tin (II) chloride.

For the calculation of the catalyst content is assumed in the case of Brönstedt acids of the neutral compound. For example, sulfuric acid is based on the molecule H2SO4 placed. If the catalyst is a Lewis acid, the catalytically active cationic species is used. For example, in the case of stannous salts, regardless of the particular counterion, only the Sn ²⁺ cation or, in the case of Ti (IV) compounds, only the Ti ⁴⁺ cation would be considered. This approach is advantageous because the content of metallic species can be determined by atomic absorption (AAS) spectroscopy without having to know the respective counterion.

In one embodiment of the polyricinoleic acid ester according to the invention, this has an acid number of> 5.2 mg KOH / g to <20 mg KOH / g. The acid number may also be in a range from> 5.4 mg KOH / g to <10 mg KOH / g.

In a further embodiment of the polyricinoleic acid ester according to the invention, this has a hydroxyl number of> 30 mg KOH / g to <80 mg KOH / g. The hydroxyl number can be determined according to DIN 53240 and may also be> 40 mg KOH / g to <60 mg KOH / g or> 45 mg KOH / g to <50 mg KOH / g.

In a further embodiment of the polyricinoleic acid ester according to the invention, this has a catalyst content of> 20 ppm to <80 ppm. The content may also be in a range from> 40 ppm to <60 ppm.

Another object of the present invention is a process for producing a polyurethane polymer, comprising the step of reacting a polyisocyanate with a polyol component comprising a Polyricinolsäureester invention. Also included within the scope of the term "polyurethane polymer" are prepolymers obtainable from the reaction of a polyisocyanate with a polyol component comprising the polyricinoleic ester of the present invention.

Suitable polyisocyanates (component B) are aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanates, e.g. by W. Siefken in Justus Liebigs Annalen der Chemie, 562, pages 75 to 136, for example those of the formula

(I)

Q (NCO) ', n, (I) in the

n = 2 - 4, preferably 2 -3, and

Q is an aliphatic hydrocarbon radical having 2 to 18, preferably 6 to 10 C atoms, a cycloaliphatic hydrocarbon radical having 4 to 15, preferably 6 to 13 C atoms, or an araliphatic hydrocarbon radical having 8 to 15, preferably 8 to 13, C atoms.

These are, for example, those polyisocyanates as described in EP-A 0 007 502, pages 7-8. Preferably, the technically readily available polyisocyanates, e.g. the 2,4- and 2,6-toluene diisocyanate, as well as any mixtures of these isomers ("TDI"); polyphenyl polymethylene polyisocyanates, as prepared by aniline-formaldehyde condensation and subsequent phosgenation ("crude MDI") and carbodiimide groups, urethane groups, allophanate groups , Isocyanurate groups, urea groups or biuret-containing polyisocyanates ("modified polyisocyanates"), especially those modified polyisocyanates derived from 2,4- and / or 2,6-toluene diisocyanate or from 4,4'- and / or 2,4 ' Preferably, at least one compound selected from the group consisting of 2,4- and 2,6-tolylene diisocyanate, 4,4'- and 2,4'- and 2,2'-diphenylmethane diisocyanate and polyphenyl polymethylene polyisocyanate is preferably used as the polyisocyanate ("Multinuclear MDI") is used, particularly preferred as the polyisocyanate is a mixture containing 4,4'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate and polyphenylpoly methylene polyisocyanate used.

The proportion of the polyricinoleic acid ester according to the invention in the polyol component may be, for example,> 5% by weight to <60% by weight, preferably> 10% by weight to <40% by weight and more preferably> 15% by weight to <30% by weight. The index gives the percentage ratio of the actual amount of isocyanate used to the stoichiometric, i. for the implementation of OH equivalents calculated amount of isocyanate groups (NCO) amount. In the reaction mixture from which the polyurethane polymer is obtained, the ratio, from NCO equivalents to OH equivalents, may range from, for example,> 80 to <120, preferably> 85 to <110.

The polyurethane formation is advantageously carried out in the presence of conventional catalysts such as tin (II) carboxylates and / or tertiary amines.

In one embodiment of this process, the polyol component further comprises a conventional polyether polyol (component AI). Among conventional polyether polyols in For the purposes of the invention compounds are referred to the alkylene oxide addition products of starter compounds having Zerewitinoff-active hydrogen atoms, ie polyether polyols having a hydroxyl number according to DIN 53240 of> 15 mg KOH / g to <80 mg KOH / g, preferably from> 20 mg KOH / g to < 60 mg KOH / g. For the conventional polyether polyols used starter compounds having Zerewitinoff-active hydrogen atoms usually have functionalities of 2 to 6, preferably from 3 to 6, more preferably from 3, and preferably the starter compounds are hydroxy-functional. Examples of hydroxy-functional starter compounds are propylene glycol, ethylene glycol, diethylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, hexanediol, pentanediol, 3-methyl-l, 5-pentanediol, 1, 12-dodecanediol , Glycerol, trimethylolpropane, triethanolamine, pentaerythritol, sorbitol, sucrose, hydroquinone, catechol, resorcinol, bisphenol F, bisphenol A, 1,3,5-trihydroxybenzene, condensates of formaldehyde and phenol or melamine or urea containing methylol groups. Preferably, the starting compound used is glycerol and / or trimethylolpropane. The use of such conventional polyols based on a starter compound having a functionality of 3 to 6 avoids the disadvantages exhibited by bifunctional polyols, such as poor deformation values (compression set). Particularly preferred are conventional polyether polyols based on a starter compound having a functionality of 3, as these also avoid the disadvantages emanating from higher functional polyols such as tetrafunctional polyols, such as their lower elongation at break.

Suitable alkylene oxides are, for example, ethylene oxide, propylene oxide, 1,2-butylene oxide or 2,3-butylene oxide and styrene oxide. Preferably, propylene oxide and ethylene oxide are fed to the reaction mixture individually, in a mixture or in succession. If the alkylene oxides are metered in succession, the products produced contain polyether chains with block structures. Products having ethylene oxide endblocks are characterized, for example, by increased levels of primary end groups, which impart advantageous isocyanate reactivity to the systems.

The invention thus also relates to the production of flexible polyurethane foams having a density according to DIN EN ISO 3386-1-98 in the range from> 10 kg / m ³ to <150 kg / m ³ , preferably from> 20 kg / m ³ to <70 kg / m ³ and a compression hardness according to DIN EN ISO 3386-1-98 in the range of> 0.5 kPa to <20 kPa (at 40% deformation and 4th cycle) by reacting component A (polyol formulation) containing

Al 50 to 95 parts by wt., Preferably 50 to 80 parts by wt. (Based on the sum of the parts by wt. Of components AI and A2) of conventional polyether polyol, A2 5 to 50 parts by wt., Preferably 20 to 50 parts by wt. (Based on the sum of the parts by wt. Of components AI and A2) of polyricinoleic acid ester obtainable by a process comprising the reaction of ricinoleic acid with an alcohol component, which comprises monohydric and / or polyhydric alcohols having a molecular mass of> 32 g / mol to <400 g / mol,

wherein the reaction is carried out at least partially in the presence of a catalyst,

characterized in that

the amount of the catalyst, based on the total mass of the ricinoleic acid and the alcohol component, in a range of> 10 ppm to <100 ppm and that the reaction is terminated when the acid number of the resulting reaction product> 5 mg KOH / g to <50 mg KOH / g, preferably> 5.2 mg KOH / g to <20 mg KOH / g, more preferably from> 5.4 mg KOH / g to <10 mg KOH / g and the reaction product has a hydroxyl value of> 30 mg KOH / g to <80 mg KOH / g, preferably from> 40 mg KOH / g to <60 mg KOH / g, more preferably from> 45 mg

KOH / g to <50 mg KOH / g,

A3 0.5 to 25 parts by weight, preferably 2 to 5 parts by weight (based on the sum of the weight.

Parts of components AI and A2) water and / or physical blowing agents,

A4 0.05 to 10 parts by wt., Preferably 0.2 to 4 parts by wt. (Based on the sum of the parts by wt. Of components AI and A2) of auxiliaries and additives such as

a) catalysts,

b) surface-active additives,

c) pigments or flame retardants,

A5 0 to 10 parts by weight, preferably 0 to 5 parts by weight (based on the sum of the parts by weight of components AI and A2) to isocyanate-reactive

Hydrogen-containing compounds having a molecular weight of 62-399,

with component B containing polyisocyanates,

wherein the preparation is carried out at a ratio of 50 to 250, preferably 70 to 130, particularly preferably 75 to 115, and

wherein all parts by weight of the components AI to A5 in the present application are normalized so that the sum of the parts by weight of the components A1 + A2 in the composition 100 results.

The components AI, A2 and B have been explained previously. Component A3

As component A3, water and / or physical blowing agents are used. As physical blowing agents, for example, carbon dioxide and / or volatile organic substances are used as blowing agents.

Component A4

As component A4, auxiliaries and additives are used as

a) catalysts (activators),

b) surface-active additives (surfactants), such as emulsifiers and foam stabilizers in particular those with low emission such as products of the Tegostab ^® LF series, c) additives such as reaction retarders (eg acidic substances such as hydrochloric acid or organic acid halides), cell regulators (such as paraffins or Fatty alcohols or dimethylpolysiloxanes), pigments, dyes, flame retardants (such as tricresyl phosphate), stabilizers against aging and weathering, plasticizers, fungistatic and bacteriostatic substances, fillers (such as

Barium sulfate, kieselguhr, carbon black or whiting) and release agents.

These optional auxiliaries and additives are described, for example, in EP-A 0 000 389, pages 18 to 21. Further examples of auxiliaries and additives which may optionally be used according to the invention and details of the use and mode of action of these auxiliaries and additives are published in the Kunststoff-Handbuch, Volume VII, by G. Oertel, Carl Hanser Verlag, Munich, 3rd edition, 1993 , eg on pages 104-127. The catalysts used are preferably aliphatic tertiary amines (for example trimethylamine, tetramethylbutanediamine), cyclic aliphatic acid amines (for example, 1,4-diaza (2,2,2) bicyclooctane), aliphatic aminoethers ( for example dimethylaminoethyl ether and N, N, N-trimethyl-N-hydroxyethyl-bisaminoethyl ether), cycloaliphatic aminoether (for example N-ethylmorpholine), aliphatic amidines, cycloaliphatic amidines, urea, derivatives of urea (such as aminoalkyl ureas, see for example EP-A 0 1 76 0 1 3, in particular (3-dimethylaminopropylamine) urea) and tin catalysts (such as dibutyltin oxide, dibutyltin dilaurate, tin octoate).

As catalysts are particularly preferred

ot) urea, derivatives of urea and / or P) amines and amino ethers, each containing a functional group which reacts chemically with the isocyanate. Preferably, the functional group is a hydroxyl group, a primary or secondary amino group. These particularly preferred catalysts have the advantage that they have a greatly reduced migration and emission behavior.

Examples of particularly preferred catalysts are: (3-dimethylaminopropylamine) - H fur, 2- (2-dimethylaminoethoxy) ethanol, N, N-bis (3-dimethylaminopropyl) -N-isopropanolamine, N, N, N-trimethyl N-hydroxyethyl bisaminoethyl ether and 3-

Dimethylaminopropylamine.

Component A5

Optionally, compounds A5 having at least two isocyanate-reactive hydrogen atoms and a molecular weight of from 32 to 399 are used as component A5. These are to be understood as meaning hydroxyl-containing and / or amino-containing and / or thiol-containing and / or carboxyl-containing compounds, preferably hydroxyl-containing and / or amino-containing compounds which serve as chain extenders or crosslinkers. These compounds generally have from 2 to 8, preferably from 2 to 4, isocyanate-reactive hydrogen atoms. For example, ethanolamine, diethanolamine, triethanolamine, sorbitol and / or glycerol can be used as component A5. Further examples of compounds according to component A2 are described in EP-A 0 007 502, pages 16-17.

The present invention further relates to a polyurethane polymer which is obtainable by a method according to the invention described above. Also included within the scope of the term "polyurethane polymer" are prepolymers obtainable from the reaction of a polyisocyanate with a polyol component comprising the polyricinoleic acid ester of the present invention.

In a further embodiment of the polyurethane polymer, this is present as polyurethane flexible foam. Flexible polyurethane foams for the purposes of the present invention are those polyurethane polymers and in particular foams whose density in accordance with DIN EN ISO 3386-1-98 in the range of> 10 kg / m ³ to <150 kg / m ³ , preferably in the range of> 20 kg / m ³ to <70 kg / m ³ and the compressive strength according to DIN EN ISO 3386-1-98 in the range of> 0.5 kPa to <20 kPa (at 40% deformation) is. The present invention will be further illustrated by the following examples.

Examples

The materials and abbreviations used have the following meaning:

Ricinoleic acid: Oleo chemistry

Tin (II) chloride: Aldrich

DABCO ^® (triethylenediamine; 2,2,2-diazabicyclooctane): Aldrich

MDI: Mixture containing 62% by weight of 4,4'-diphenylmethane diisocyanate, 8% by weight

2,4'-diphenylmethane diisocyanate and 30% by weight multi-core MDI with an NCO content of 32.1% by weight

PET: polyether polyol having an OH number of about 28 mg KOH / g, prepared by

Addition of propylene oxide and ethylene oxide in the ratio 85 to 15 under

Use of glycerol as a starter with about 85 mol% primary OH groups. Tegostab ^® B 8681: Preparation organo-modified polysiloxanes, Evonik Goldschmidt Addocat ^® 105: amine catalyst from Rhein Chemie

Addocat ^® 108: amine catalyst from Rhein Chemie

Addocat ^® SO: tin catalyst from Rheinchemie

The analyzes were carried out as follows:

Dynamic viscosity: Rheometer MCR 51 of the company Anton Paar according to DIN 53019 with a measuring cone CP 50-1 (diameter 50 mm, angle 1 °) at shear rates of 25, 100, 200 and 500 s ^"1. The polyricinolates show shear rate independent viscosities.

Hydroxyl number: based on the DIN 53240 standard

Acid value: based on the DIN 53402 standard

A) Preparation of the polyricinolate

Example A-1 (according to the invention):

343 kg of ricinoleic acid and 22 kg of hexanediol were drawn into a 500 liter stirred tank and heated to 200 ° C. under nitrogen with stirring (running time approx. 2 hours). In this case, water of reaction was first distilled off at normal pressure. After a running time of 14 hours no more water distilled. There was the addition of 65.4 g of a 28% solution of tin dichloride (anhydrous) in ethylene glycol. After completion of the addition of catalyst slowly vacuum was applied to last 30 mbar (running time to here: 17 hours), the head temperature did not exceed 100 ° C. The reaction was continued for a total run time of 22 hours at 200 ° C and 30 mbar. Then the properties were determined: Analysis of the resulting polyricinolate Al:

Hydroxyl number: 46.8 mg KOH / g

Acid number: 5.42 mg KOH / g

Viscosity: 800 mPas (25 ° C)

Catalyst concentration: 33.5 ppm tin in the final product

Example A-2V (comparative example):

In a 16000-liter stirred tank with distillation columns and attached dephlegmator 13000 kg of ricinoleic acid and 650 kg of hexanediol were drawn and heated with stirring to 200 ° C. During the heating phase, water of reaction was distilled off under atmospheric pressure. Upon reaching the reaction temperature, vacuum was applied. The pressure was lowered within one hour to 20 mbar. Meanwhile, the head temperature was maintained at the level of the water boiling line by regulating the dephlegmatist temperature. At a pressure of 200 mbar, 320 g of a 28% strength solution of tin dichloride (anhydrous) in ethylene glycol were added after 3.5 hours. At the same time, the dephlegmatist temperature was fixed at 60 ° C. The acid value was monitored in the course of the further reaction: the acid number was 10 mg KOH / g after a reaction time of 24 hours, 5 mg KOH / g after 48 hours, 3.5 mg KOH / g after 72 hours and 3 hours after 84 hours , 0 mg KOH / g. After 84 hours reaction time, the reactor contents were cooled to 130 ° C.

Analysis of the resulting polyricinolate A2-V:

Hydroxyl number: 37.5 mg KOH / g

Acid value: 3.0 mg KOH / g

Viscosity: 850 mPas (25 ° C)

Catalyst concentration: 4 ppm Sn in the final product

Example A-3V (comparative example):

In a 10-liter four-necked flask equipped with mechanical stirrer, 50 cm Vigreux column, thermometer, nitrogen inlet, and column head, distillation bridge and vacuum membrane pump, 7775 g of ricinoleic acid (about 24 mol) and 657 g (5.57 mol) 1, 6- hexanediol and under nitrogen over a period of 60 min. heated to 200 ° C, with water of reaction was distilled off. After 8 hours, 480 mg of tin dichloride dihydrate were added and the reaction continued. After a total reaction time of 17 hours, the pressure was slowly reduced to 15 mbar over 5 hours. In the course of the further The acid number was followed: After a reaction time of 45 hours in total, the acid number was 7.5 mg KOH / g, after 76 hours 3.0 mg KOH / g, after 100 hours 2.9 mg KOH / g.

Analysis of the resulting polyricinolate A-3V:

Hydroxyl number: 53.3 mg KOH / g

Acid value: 2.9 mg KOH / g

Viscosity: 325 mPas (25 ° C) 100 mPas (50 ° C) 45 mPas (75 ° C)

Catalyst concentration: 4 ppm Sn in the final product

Table 1: Overview of the polyricinolates A-1, A-2 V and A-3 V

The technical advantage of the polyricinolate A-1 according to the invention is evident from the greatly shortened transit time compared to A-2V and A-3V.

Examples A-4 V, A-5, A-6 and A-7

The preparation of the polyricinolates A-4 V, A-5, A-6 and A-7 was carried out in accordance with the procedure described above for Comparative Example A-3 V, wherein the amounts indicated in Table 2 were used. The respective reaction time and the analysis of the resulting polyricinolate are given in Table 2.

Table 2: Overview of Polyricinolates A-4 V, A-5, A-6 and A-7

The following examples (Section B) show that the processing and product properties of the flexible polyurethane foams produced from the polyricinolates Al, A-5, A-6 and A-7 according to the invention versus flexible polyurethane foams based on A-2V, A-3V and A-4V are comparable.

B) Production of polyurethane flexible foams

In the usual way for the production of polyurethane soft block foams processing method according to the one-step process, the starting materials listed in the following Tables 3 and 4 are reacted with each other in the examples: The index (isocyanate index) indicates the percentage ratio of the actual amount of isocyanate used stoichiometric, ie for the conversion of OH equivalents calculated amount of isocyanate groups (NCO) amount of:

Code = [(amount of isocyanate used): (calculated amount of isocyanate)] × 100 (II)

The obtained polyurethane soft block foams were subjected to optical evaluation. The classification of the polyurethane soft foam ("foam evaluation") was based on a scale of coarse - medium - fine, where a classification "coarse" means that the foam has less than about 5 cells per cm. that the foam has more than about 5 cells per cm and has less than about 12 cells per cm and a rating of "fine" means that the foam has more than about 12 cells per cm. The classification of foam quality in terms of cell structure was based on a scale of poor - medium - good. Here, a classification "bad" means that the foam does not have a uniform cell structure and / or visible defects. A "medium" rating means that the foam has a predominantly uniform cell structure with few visible defects, and a "good" rating means that the foam has a uniform cell structure with no visible defects.

Table 3: Preparation and evaluation of polyurethane flexible foams

Abbreviations: Cf. = Comparative Example; Gew. -Tie. = Parts by weight; MV = weight ratio of component A to component B at the given index and based on 100 parts by weight of component A. The polyurethane soft block foams in which the Polyricinolat AI invention have been processed, are identical in terms of processing and properties with foams from the comparative example. As can be seen, the polyol A-2V or A-3V can be replaced with a synthesis time of about 84 hours or 100 hours without changing the recipe by a polyol according to the invention Al with a synthesis time of about 20 hours (Table 3).

Table 4: Preparation and evaluation of flexible polyurethane foams

Abbreviations: see table 3

The polyurethane soft block foams B-5, B-6 and B-7, in which the polyricinolate A-5, A-6 and A-7 according to the invention were processed, are in terms of properties at a comparable level with the foams of the comparative example B- 4V. As the acid number of the polyricinolate increases, the rise time of the foams and the bulk density increase. As example B-8 shows, a longer rise time and a higher bulk density can be counteracted by an increased amount of catalyst. The foams B-5, B-6 according to the invention, B-7 and B-8 are identical in foam evaluation and cell structure to Comparative Example B-4V.

Claims

Process for the production of flexible polyurethane foams with a density according to DIN EN ISO 3386-1-98 in the range from> 10 kg / m ³ to <150 kg / m ³ and a compression hardness according to DIN EN ISO 3386-1-98 in the range of> 0 , 5 kPa to <20 kPa (at 40% deformation and 4th cycle) by reaction of

Containing component A.

Al 50 to 95 parts by weight (based on the sum of the parts by weight of components A 1 and A2) conventional polyether polyol,

A2 5 to 50 parts by weight (based on the sum of the parts by weight of components AI and A2) Polyricinolsäureester obtainable by a process comprising the step of the reaction of ricinoleic acid with an alcohol component, which mono- and / or polyhydric alcohols with a molecular weight of> 32 g / mol to <400 g / mol,

characterized in that

the amount of the catalyst, based on the total mass of the ricinoleic acid and the alcohol component, in a range of> 10 ppm to <100 ppm and that the reaction is terminated when the acid number of the resulting reaction product> 5 mg KOH / g to <50 mg KOH / g is,

A3 0.5 to 25 parts by weight (based on the sum of the parts by weight of components AI and A2) of water and / or physical blowing agents,

A4 0.05 to 10 parts by weight (based on the sum of parts by weight of components AI and A2) auxiliaries and additives such as

a) catalysts,

b) surface-active additives,

c) pigments or flame retardants,

with component B containing polyisocyanates,

wherein the production takes place at a ratio of 50 to 250, and wherein all parts by weight of the components AI to A5 in the present application are normalized so that the sum of the parts by weight of the components AI + A2 in the composition 100 results.

2. The method according to claim 1, wherein A2 has an acid number of> 5.2 mg KOH / g to <20 mg KOH / g.

3. The method according to claim 1 or 2, wherein A2 has a hydroxyl value of> 30 mg KOH / g to <80 mg KOH / g.

A process according to any one of claims 1 to 3, wherein A2 is obtainable by a process having a catalyst content of> 20 ppm to <80 ppm.

A process according to any one of claims 1 to 4, wherein A2 is obtainable by a process characterized in that the catalyst comprises tin (II) salts.

6. A polyurethane polymer obtainable by a process according to any one of claims 1 to 5.

7. A polyurethane polymer according to claim any one of claims 1 to 5, in the present case as a flexible polyurethane foam.

8. A process for preparing polyricinoleic acid esters comprising the step of reacting ricinoleic acid with an alcohol component comprising mono- and / or polyhydric alcohols having a molecular weight of from> 32 g / mol to <400 g / mol,

wherein the reaction is carried out at least partially in the presence of a catalyst, characterized in that

the amount of the catalyst, based on the total mass of the ricinoleic acid and the alcohol component, is in a range from> 10 ppm to <100 ppm, and that the reaction is terminated when the acid number of the resulting reaction product> 5 mg

KOH / g to <50 mg KOH / g.

A process according to claim 8, wherein the molar ratio of ricinoleic acid and the alcohol component is in a range of> 3: 1 to <10: 1.

10. The method according to claim 8 or 9, wherein the alcohol component is 1,4-dihydroxycyclohexane, 1,2-butanediol, 1,3-propanediol, 2-methylpropanediol-l, 3, 1, 4-butanediol, 1,5- Pentanediol, 1,6-hexanediol, neopentyl glycol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, cyclohexanedimethanol, glycerol and / or trimethylolpropane.

A process according to any one of claims 8 to 10 wherein the catalyst comprises stannous salts.

12. The method according to any one of claims 8 to 11, wherein the reaction time is> 10 hours to <30 hours.

13. The method according to any one of claims 8 to 11, wherein the reaction temperature is> 150 ° C to <250 ° C.

14. The method according to any one of claims 8 to 12, wherein initially ricinoleic acid and the alcohol component are reacted without catalyst, the catalyst is then added, when the water-forming reaction has come to a standstill and then the reaction is catalysed further carried out.