WO2008064966A1

WO2008064966A1 - Polyurethane thickening agents for thickening aqueous systems

Info

Publication number: WO2008064966A1
Application number: PCT/EP2007/061658
Authority: WO
Inventors: Eberhard Esselborn; Jürgen Kirchner; Ellen Reuter
Original assignee: Evonik Goldschmidt Gmbh
Priority date: 2006-11-30
Filing date: 2007-10-30
Publication date: 2008-06-05
Also published as: DE102006056509A1

Abstract

The invention relates to polyurethane thickening agents that are obtained by a method comprising the steps of reacting A) at least one alcohol component with B) at least one isocyanate component. Said method is characterized in that prior to the complete reaction of the isocyanate component B) a compound C) of the general formula (I) R1-O-(SO)a-(EO)b-(PO)c-(BO)d-(DTO)e(TTO)f-R2 is added and the reaction is continued until substantially no NCO groups remain.

Description

Polyurethane thickener for thickening aqueous systems

The invention relates to novel, suitable as thickeners for aqueous systems hydrophilic / hydrophobic water-soluble or -dispersible polyurethanes, which are characterized by a particularly low viscosity with simultaneous efficient thickening effect, as well as their use for thickening aqueous systems.

A variety of polyurethane-based associative thickeners are known. These are linear or branched, usually nonionic, surfactants with discrete hydrophilic and hydrophobic domains. Their typical structures, their preparation and use is described inter alia in US Pat. No. 4,155,892 or US Pat. No. 4,079,028.

The polyurethane thickeners are made from

(a) at least one water-soluble polyether polyol,

(b) at least one water-insoluble organic polyisocyanate,

(c) at least one monofunctional hydrophobic organic compound selected from compounds having an isocyanate-active hydrogen atom or organic monoisocyanates and

(d) at least one polyfunctional alcohol or polyfunctional ether alcohol.

EP 0 307 775 describes water-dispersible, modified polyurethane thickeners which are prepared from (a) a polyisocyanate, (b) a polyether polyol, (C) a modifying agent having at least 2 active hydrogen atoms and at least one hydrophobic group, wherein the modifying agent contains no groups that can react with polyisocyanate or the polyether polyol, and

(d) an end-capping agent, such as alkoxylated alcohols.

US Pat. No. 4,327,008 describes star-shaped polyurethane thickeners. The reaction products are out

(a) polyether diols,

(b) polyether polyols or isocyanates having a functionality> 3, (c) a diisocyanate,

(d) 37 to 175 mol% of water (based on the polyether diol) and

(e) an end-capping monool or monoisocyanate.

Polyurethane thickeners of the type mentioned and their preparations are suitable as auxiliaries for adjusting rheological properties of aqueous systems, for example paints such as automotive and industrial coatings, plasters and architectural paints, printing inks, pigment pastes, filler dispersions or cosmetic and pharmaceutical preparations, crop protection formulations as described in US Pat 4,155,892, US 4 079 028, EP 0 307 775, US 4 327 008, EP 0 031 777, EP 0 495 373, US 4 499 233, US 4 426 485, DE 41 01 239 and US 5 023 309.

All of these prior art polyurethanes have in common that hydrophilic segments are present in an amount of at least 50% by weight, at most 10% by weight of hydrophobic segments and urethane groups. Hydrophilic segments are in particular high molecular weight polyether chains which are preferably made of ethylene oxide polymers. stand, understand. Hydrophobic segments are to be understood as meaning hydrocarbon chains having> 3 C atoms, in particular at least six to eighteen carbon atoms.

It is known that thickeners with good activity can only be obtained if the hydrophilic polyether segments (overall) have a molecular weight of at least 3000 g / mol and almost exclusively, preferably> 50 wt .-%, consist of polyethylene oxide, the hydrophobic Segments have at least 8 carbon atoms and hydrophilic and hydrophobic segments in a weight ratio of 92 to 97 wt .-% to 8 to 3 wt .-% present.

In addition, these polyurethanes should have the lowest possible intrinsic viscosity so that they can be handled and processed without difficulty, if appropriate in the form of very highly concentrated solutions. This requirement, for example, prohibits the obvious production of long hydrophilic segments by chain-extending reaction of comparatively low molecular weight polyether diols with diisocyanates, because the associated higher number of urethane groups results in an undesirable increase in intrinsic viscosity. This complicates the incorporation and processing in water-dilutable systems.

Recently, many attempts have been made to lower the inherent viscosity of the thickening agents. However, those skilled in the art will appreciate that mere molecular weight reduction is accompanied by a deterioration in thickening efficiency. Another possibility is based on the addition of typical emulsifier structures (DE 196 00 467), in particular also acetylenediol derivatives (EP 0 618 243). The additional addition of diesters is described (DE 196 44 933). In the US Patent No. 5,597,406, a diol or a diol monoalkyl ether, a salt of a sulfated nonylphenol ethoxylate and organic phosphoric acid esters are proposed for the formulation.

These processes initially have the disadvantage that the additives described have to be added to the thickening agents in high concentrations in order to achieve a satisfactory reduction in the intrinsic viscosity of the thickener. In addition, a number of other disadvantages are associated with this, such as the foam stabilization of the thickener preparations caused by these additives, in particular their aqueous formulations, such as, for example, dispersion-based architectural paints. In addition, the additive entry undesirably deteriorates the water and weather resistance of coating systems and, in the case of building paints, their abrasion resistance. In addition, the very powerful alkylphenol ethoxylates have come under criticism for ecotoxicological reasons, and their use is already legislated.

Another common method known from the literature to reduce the intrinsic viscosity of aqueous solutions of polyurethanes is the addition of water-soluble or water-miscible solvents, such as, for example, alcohols or glycol derivatives. The decisive disadvantage of this method, however, is that it undesirably introduces solvents into environmentally compatible coating systems, which runs counter to the idea of reducing VOCs.

It is known that the problems described occur increasingly with extremely pseudoplastic, branched polyurethane thickeners. Applications of styrene oxide-containing block copolymers are still largely unknown in the paint and printing ink industry. Inter alia (EP 0 940 406) are known polystyrene oxide (block) -polyalkylenoxid copolymers, which, starting from a monofunctional starting alcohol, are reacted by sequential addition of at least 2 moles of styrene oxide and an alkylene oxide and subsequent phosphorylation to the corresponding phosphoric acid esters.

These block copolymers are particularly useful in their neutralized form, e.g. as sodium or potassium salt, used as dispersants. Due to the electrolyte content, however, the use in larger amounts for the formulation of paints and varnishes is not always suitable. If these compounds enter the environment, their lack of rapid biodegradability due to the presence of longer styrene oxide blocks is unacceptable.

It is an object of the present invention to provide new polyurethane thickeners and low-foaming and VOC (volatile organic compound) -free preparations produced therefrom which are easy to handle and dose, have a low intrinsic viscosity in the preparation and in the final formulation are partially extreme have thickening effect both for Newtonian and pseudoplastic aqueous systems and in particular have no negative impact final coating properties such as abrasion resistance and weathering resistance.

This object could be achieved with the hydrophilic / hydrophobic water-soluble or -dispersible polyurethanes according to the invention, described in more detail below. Essential to the invention here is the targeted incorporation of selected hydrophilic segments by using a spe- ziellen polyether as a reaction partner for the isocyanate component.

An object of the invention are therefore polyurethane thickeners obtained by a process comprising the reaction of

A) at least one alcohol component with

B) at least one isocyanate component,

which is characterized in that before the full ^¬ continuous reaction of the isocyanate component B) a compound C) of the general formula (I)

R ^ O (SO) _a - (EO) _b - (PO) c- (BO) _d - (DTO) _e (TTO) _f -R ²

(D

wherein the substituents and indices mean:

R ¹ , R ² = independently of one another a hydrogen radical, an optionally substituted and / or multiple bonds and / or heteroatoms containing aliphatic, cycloaliphatic C ₆ - to C ₂ 2 ~ hydrocarbon radical, preferably C ₈ - to C ₈ - hydrocarbon radical, an optionally aromatic and / or heteroatom-containing aromatic radical having 6 to 20 C atoms, preferably 10 to 16 C atoms, with the proviso that at least one of the radicals is or contains a hydrogen atom which is reactive toward isocyanur groups,

SO = styrene oxide residue, EO = ethylene oxide residue, PO = propylene oxide residue, BO = butylene oxide residue, DTO = dodecene oxide, TTO = tetradecenoxide, a = 0 to 3, b = 3 to 30, preferably 5 to 15, c = 0 to 5, preferably 0 to 2, d = 0 to 5, preferably 0 to 2, e = 0 to 5, preferably 0 to 2, f = 0 to 5,

with the proviso that s (a + c + d + e + f) is added, and the reaction is continued until substantially no more NCO groups are present.

The preparation of the thickener according to the invention is carried out initially in a conventional manner by the OH-functional components according to the prior art with di-, tri- or polyisocyanates and optionally monoisocyanates, preferably while maintaining an NCO / OH equivalent ratio of 0.8: 1 to 1.2: 1, are reacted. Towards the end of the reaction, i. Before all isocyanate groups have been reacted, at least one compound C) is added at the optimum time in amounts, based on the still free NCO groups, of from 0.8 to 5.0 equivalents, and the reaction is continued until there are essentially no more NCO groups available.

The optimum time of addition is the point where, at the lowest melt viscosity, the final product has the highest thickening effect. It depends on the type and quantity of the components and differs for each product, but can be determined through some preliminary preliminary tests. Starting with a low viscosity, the addition times are increasingly shifted to higher viscosities and the associated thickening effects determined. The melt viscosity can be determined by the usual methods. The viscosity should be in a range that easily allows the usual processing methods such as stirring, pouring, spraying, pumping. In the range of 500 to 50,000 mPas, preferably 1000 to 5000 mPas measured using a rotation viscometer from Haake 550VT, at 80 ⁰ C according to the manufacturer's specifications. According to the invention, it is preferably determined via the torque of the stirrer.

The alcohol component A) can be selected from the compounds known from the prior art. Preferred alcohols are polyether polyols such as polyethylene glycol, random and block copolymers of diols, consisting of ethylene glycol and / or propylene glycol and / or butylene glycol. Preference is given to polyether polyols such as polyethylene glycol and mixtures of two polyethylene glycols of different molecular weight.

The isocyanate component B) is preferably difunctional. Higher functionality polyisocyanates can be used as part of the total isocyanate requirement. To avoid unwanted crosslinks, i. Although monofunctional isocyanates can be used to form highly viscous gels, tri- and higher-functional polyisocyanates should be included in less than about 20 mole percent, preferably less than 10 mole percent, based on the total amount of isocyanate used.

According to the invention, one or more isocyanates selected from the group consisting of 1, 6-hexamethylene diisocyanate; 1,4-tetramethylene diisocyanate; 1, 10-decamethylene disocyanate; 1,4-cyclohexylene diisocyanate; 4,4'-methylenebis (isocyanato-cyclohexane); α, α, α ', α'-tetramethyl-m-xylylenes diisocyanate = TMXDI from Cytec; Vestanat® IPDI = 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethylcyclohexane; m-phenylene diisocyanate; p-phenylene diisocyanate; 2,6- and 2,4-tolylene diisocyanate; Xylene diisocyanate; 4-chloro-1,3-phenylene diisocyanate; 4,4'-biphenylene diisocyanate; 4, 4 '-methylenediphenylisocyanate; 1, 5-naphthylene diisocyanate; 1,5-tetrahydronaphthylene diisocyanate; a product called Vestanat TMDI, made by Huls America, Inc., which is a 40:60 blend

(by weight) of 2, 2, 4-trimethylhexamethylene-1,6-diisocyanate and 2,4,4-trimethylhexamethylene-1,6-diisocyanate; Polymethylenepolyphenyl isocyanates sold under the trade name "PAPI" such as "PAPI 135" (equivalent weight 133.5 and average isocyanate functionality 2.7) and "PAPI 901" (equivalent weight 133 and average isocyanate functionality 2.3), the aromatic triisocyanate adduct of Trimethylolpropane and tolylene diisocyanate sold under the trade name "Mondur CB-75"; the aliphatic triisocyanate product of the hydrolytic trimerization of 1,6-hexamethylene diisocyanate sold under the tradename "Desmodur N"; C "diisocyanate diisocyanate sold under the tradename" DDI "based on dimer acids as discussed in J. Am. OiI Chem. Soc. 51, 522 (1974), and mixtures thereof. Preferred polyisocyanates are 1,6-hexamethylene diisocyanate; Vestanat® IPDI; Vestanat TMDI; the 2,6- and 2,4-tolylene diisocyanates and mixtures thereof.

If monofunctional and / or trifunctional isocyanates are also used, the average NCO functionality should be in the range of about 1.5 to 2.5, preferably 1.8 to 2.2, in particular 1.9 to 2.1.

Monoisocyanates preferably used according to the invention are stearyl isocyanate and lauryl isocyanate. According to the invention preferably used / used higher-functional polyisocyanates are trimerized 1,6-hexamethylene diisocyanate (Desmodur N) and trimerized isophorone diisocyanate (Vestanat T1890-100). Component C) used according to the invention is preferably one or more compounds in which in the general formula (I)

C _{8 to} s Cl 8 /

R ² H and

A 0 or 1

is.

The essential characteristic of component C) is the length and structural composition of the hydrophobic part and the length and the structural structure of the hydrophilic part. These polyether segments may be present in the form of a mixture in a distribution governed essentially by statistical laws, or the arrangement of the various alkylene oxide monomers may be blockwise, the blockwise arrangement being preferred, in particular that in which the styrene oxide, dodecene oxide or butylene oxide is directly attached the starting alcohol R ¹ OH is polymerized.

Particular preference is given to compounds having a structure similar to that of nonylphenol, consisting of the starting alcohol iso-nonanol (2, 2, 4-trimethylhexanol) which has been alkoxylated with 1.2 mol of styrene oxide and 10 mol of ethylene oxide, or ethoxylates based on fatty alcohols 8 to 18 carbons and 3 to 20 moles of ethylene oxide.

With the help of polyurethane thickeners, the rheological properties of eg paints can be adjusted. For a paint, which is sprayed especially on vertical surfaces, you need a pseudoplastic flow behavior, so that the paint does not expire after application. For a paint that is applied with a brush, you need a Newtonian or a "high shear" rheology profile, which causes the painter to apply a so-called "paint brake" to a solvent-based paint The radical R ¹ in the formula (I) is of particular importance: the required rheology profiles can be influenced particularly well by varying the component R ¹ in the formula (I) ₀ to C ₄ - alkyl radical preferably, at a "high shear" thickeners of the radical R ¹ is preferably a C ₆ - to C _O alkyl group, and at a pseudoplastic thickener is a C ₆ - to

C ₂ o-alkyl group used.

Another object of the invention are suitable as thickeners for aqueous systems, water-soluble or -dispersible polyurethanes, prepared by a method according to claim 1.

Further objects of the invention are characterized by the subject matters of the claims.

In the following Ausführungsbespielen the preparation of the polyurethane thickener is described in detail.

embodiments

Synthesis of the polyalkylene oxide No. Al

1464 g (10.2 mol) of 3, 5, 5-trimethylhexanol and 80.7 g

(1.15 mol) of potassium methylate are placed in a reactor.

After careful flushing with pure nitrogen is on

110 C heated, and there are added 1383 g (11.5 mol) of styrene oxide within one hour. After a further two hours, the addition of the styrene oxide is complete, recognizable by a residual content of styrene oxide, which is <0.1 wt .-% according to gas chromatography. Subsequently, 5072 g (115 mol) of ethylene oxide are metered into the reactor so quickly that the internal temperature does not exceed 120 C and the pressure does not exceed 6 bar. After complete introduction of the ethylene oxide, the temperature is maintained at 115 C until a constant gauge pressure indicates the end of the post-reaction. Finally, at 80 to 90 C, the unreacted residual monomers are removed in vacuo. The product obtained is neutralized with the aid of phosphoric acid and the water is removed by distillation, and the resulting potassium phosphate is removed by filtration together with a filter aid. The molecular weight from the determination of the hydroxyl number assuming a functionality of 1 is M = 684 g / mol.

The skilled worker is familiar with the fact that the order of alkoxylation can be chosen arbitrarily. Because of the high reactivity of the lower epoxides and the lower reactivity of the higher epoxides, the route chosen in the art is generally that the epoxides with the lower reactivity are first attached to the starting molecule. In special cases, however, it may be necessary to add the styrene oxide and the higher alkylene oxides to exploit the particular physicochemical properties of the free OH group. The compounds A2 to AlO to be used according to the invention are prepared in an analogous manner by the processes which correspond to the prior art.

Table 1:

Synthesis of polyurethanes

Polyurethane BlA (pseudoplastic thickener) 1683 g of polyether PPG 6000 with the OHZ 20 mg KOH / g are introduced into the dry reactor under N ₂ . The agitator of the reactor is equipped with a torque measurement. For dehydration of the polyether this is mixed in the reaction vessel with 10 wt .-% toluene (based on the amount used), heated to 110 ⁰ C and with slow increase in the vacuum to last <15 mm and a slight Stickstoffström for 1 hour at maximum vacuum dewatered. The water content (according to Karl Fischer) should be <0.03%. At higher water content, the drainage time is extended accordingly. After drying, the batch is allowed to cool to 80 ⁰ C. Now, 46.6 g of Vestanat® IPDI (isophorone diisocyanate) having an NCO index of 1.05 and 59.0 g of stearyl isocyanate are added to the liquid reaction mixture.

First, the isocyanates are intimately mixed with the OH-functional component. Then, the addition of 1.8 g of dibutyltin dilaurate. In this case, a slight, exothermic reaction can be seen, the temperature increase is about 10 C. The viscosity of the reaction mixture is now increasing continuously, which is clearly visible in the torque.

After 6 hours, a reaction is monitored by determining the NCO content. At an NCO value of <0.01%, the reaction is largely complete. The difference of the torque at the beginning and at the end is about 90 Ncm.Man receives a solid at room temperature, slightly fragile wax. In the ground state, it is storable without being sintered together and of light color.

Polyurethane BlB

The example BlA is repeated in the same apparatus except that after 1 hour and a difference of the torque of 70 Ncm the compound A2 is added in an amount of 89.4 g. The torque increases only marginally.

Polyurethane blc

For comparison, the polyurethane of Example BlA is mixed with the compound A2 only, so that the same composition is obtained gross as in Example BlB. Polyurethane B2A (Newtonian thickener) 1683 g of polyether PEG 6000 with the OHZ 20 mg KOH / g are introduced into the dry reactor under N ₂ . The agitator of the reactor is equipped with a torque measurement. For dehydration of the polyether this is mixed in the reaction vessel with 10 wt .-% toluene (based on the amount used), heated to 110 ⁰ C and with slow increase in the vacuum to last <15 mm and a slight Stickstoffström for 1 hour at maximum vacuum dewatered. The water content (according to Karl Fischer) should be <0.03%. At higher water content, the drainage time is extended accordingly. After drying, the batch is allowed to cool to 80 ° C.

Now, 93.2 g of Vestanat® IPDI (isophorone diisocyanate) having an NCO index of 1.05 and 31.6 g of n-decanol are added to the liquid reaction mixture.

First, the isocyanates are intimately mixed with the OH-functional component. Then, the addition of 1.8 g of dibutyltin dilaurate. In this case, a slight, exothermic reaction can be seen, the temperature increase is about 20 ⁰ C. The viscosity of the reaction mixture is now increasing continuously, which is clearly visible in the torque.

After 6 hours, a reaction is monitored by determining the NCO content. At an NCO value of <0.01%, the reaction is largely complete. The difference of the torque at the beginning and at the end is about 91 Ncm.Man receives a solid at room temperature, slightly fragile wax. In the ground state, it is storable without being sintered together and of light color. Polyurethane B2B

Example B2A is repeated in the same apparatus with the difference that after 1 hour and a difference of the torque of 70 Ncm, the compound Al is added in an amount of 88 g. The torque increases only marginally.

Polyurethane B2C

For comparison, the polyurethane of Example B2A is mixed with the compound Al only, so that the same composition is obtained gross as in Example B2B.

Polyurethane B3A

Example B3A is repeated in the same apparatus according to the method described in Example B2A with the following raw materials: 1683 g of PEG 6000, 87.45 g of isophorone diisocyanate and 23.7 g of n-decanol. The torque after 6 hours is 97 Ncm.

Polyurethane B3B

The polyurethane described in Example B3A is prepared with the difference that 90 g of compound A3 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B3C

For comparison, the polyurethane of Example B3A is compounded with compound A3 only, so that the same composition is obtained grossly as in Example B3B.

Polyurethane B4A

Example B4A is repeated in the same apparatus according to the method described in Example B1A with the following raw materials: 1683 g of PEG 6000, 27.4 g of hexamethylene diisocyanate and 45.7 g of stearyl isocyanate. The torque after 6 hours is 95 Ncm. Polyurethane B4B

The polyurethane described in Example B4A is prepared with the difference that 90 g of compound A4 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B4C

For comparison, the polyurethane of example B4A is mixed with compound A4 so that the same composition is obtained grossly as in example B4B.

Polyurethane B5A

Example B5A is repeated in the same apparatus according to the method described in Example B2A with the following raw materials: 1683 g of PEG 6000, 124 g of isophorone diisocyanate and 33.0 g of n-dodecanol. The torque after 6 hours is 97 cm.

Polyurethane B5B

The polyurethane described in Example B5A is prepared with the difference that 90 g of compound A5 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B5C

For comparison, the polyurethane of example B5A is mixed with the compound A5 so that the same composition is obtained grossly as in example B5B.

Polyurethane B6A

Example B6A is repeated in the same apparatus according to the method described in example B1A with the following raw materials: 1683 g of PEG 6000, 36.5 g of tolylene diisocyanate and 59.0 g of stearyl isocyanate. The torque after 6 hours is 88 Ncm. Polyurethane B6B

The polyurethane described in Example B6A is prepared with the difference that 90 g of the compound A6 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B6C

For comparison, the polyurethane of example B6A is mixed with compound A6 so that the same composition is obtained grossly as in example B6B.

Polyurethane B7A

Example B7A is repeated in the same apparatus according to the method described in Example B2A with the following raw materials: 1683 g of PEG 6000, 82.6 g of isophorone diisocyanate and 28.1 g of n-decanol. The torque after 6 hours is 98 Ncm.

Polyurethane B7B

The polyurethane described in Example B7A is prepared with the difference that 90 g of compound A7 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B7C

For comparison, the polyurethane of example B7A is mixed with compound A7 so that the same composition is obtained grossly as in example B7B.

Polyurethane B8A

Example B8A is repeated in the same apparatus according to the method described in example B1A with the following raw materials: 1450 g PEG 6000, 295 g PEG 3000, 51.5 g tetramethylxylylene diisocyanate and 59.0 g stearyl isocyanate. The torque after 6 hours is 89 Ncm. Polyurethane B8B

The polyurethane described in Example B8A is prepared with the difference that 90 g of compound A8 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B8C

For comparison, the polyurethane of example B8A is mixed with compound A8 so that the same composition is obtained grossly as in example B8B.

Polyurethane B9A

Example B9A is repeated in the same apparatus according to the method described in Example B2A with the following raw materials: 1683 g of PEG 6000, 93.2 g of isophorone diisocyanate and 31.6 g of n-decanol. The torque after 6 hours is 92 Ncm.

Polyurethane B9B

The polyurethane described in Example B9A is produced with the difference that 90 g of compound A9 are added at a torque of 70 Ncm. The torque increases only insignificantly on.

Polyurethane B9C

For comparison, the polyurethane of example B9A is mixed with compound A9 so that the same composition is obtained grossly as in example B9B.

Polyurethane BlOA

The example BlOA is repeated in the same apparatus according to the method described in Example B2A with the following raw materials: 1683 g of PEG 6000, 93.2 g of isophorone diisocyanate and 31.6 g of n-decanol. The torque after 6 hours is 90 Ncm. Polyurethane blOB

The polyurethane described in the example BlOA is produced with the difference that 90 g of the compound AlO are added at a torque of 65 Ncm. The torque continues to increase by 5 units to 70 Ncm.

Polyurethane BlOC

For comparison, the polyurethane of example BlOA is mixed with the compound AlO, so that the same composition is obtained grossly as in example BlOB.

Formulation of polyurethanes

Examples FlA-FlOC

With good mixing, the respectively required amount of water and optionally the emulsifier having the structure trimethylhexanol (SO) i- (EO) ₁₀ -OH are added to the 80 ^° C. polyurethane and stirring is continued until a homogeneous solution results. The viscosities of the solutions thus obtained are measured after 24 hours of service life. The measurement is carried out with the rheometer RS1 from Thermo Electron with the cone / plate measuring system HC35 according to DIN 5318 at 23 ° C. and a shear rate of 10.3 sec ^-1 . The measured values are listed in the following table.

Table 2: Formulations of polyurethane thickeners

Without the addition of a compound of the general formula (I), the solutions have a significantly higher viscosity than when adding such a compound. In particular, in the case of partial, chemical incorporation of a compound of the general formula (I), the viscosity is lowered to about half.

Application examples

The following examples with the dispersions Acronal 290 D (manufacturer BASF) and Mowilit LDM 7416 (manufacturer Celanese) show that the addition of the viscosity-lowering component during the reaction does not affect the thickening effect of the polyurethane component in the application ultimately.

2.5 g of the listed thickener formulations of the pseudoplastic thickener (Table No. 3) or 0.9 g of the listed thickener formulations of the Newtonian thickener (Table No. 4) are admixed with 100 g of the approximately 22 ° C. dispersion Mixing homogenized at 1000 rpm with the Dispermate VMA Fa. Getzmann. The viscosities of the solutions thus obtained are determined after a service life of 24 hours. The measurement is made with the rheometer RSl Fa. Thermo Electron with the cone / plate measuring system HC35 according to DIN 5318 at 23 ⁰ C and a shear rate of 10.3 sec ^'1. The measured values are listed in the following tables.

Table No. 3: Application of a Pseudoplastic Thickener

Table 4: Application of a Newtonian thickener

By the examples listed in Tables 3 and 4 it can be shown that by partial incorporation of a compound of general formula (I) in the thickener molecule with Newtonian as well as pseudoplastic properties, the viscosity of the thickener preparations can be greatly reduced without the Thickening properties are thereby adversely affected.

Claims

Claims:

1. polyurethane thickener, obtained by a Ver ^¬ drive containing the implementation of

A) at least one alcohol component with

B) at least one isocyanate component,

which is characterized in that, prior to the complete reaction of the isocyanate component B), a compound C) of the general formula (I)

PJ-O- (SO) _a - (EO) _b - (PO) c- (BO) _d - (DTO) _e (TTO) _f -R ²

(D wherein the substituents and indices mean:

R ¹ , R ² = independently of one another a hydrogen radical, an optionally substituted and / or multiple bonds and / or hetero atoms containing aliphatic, cycloaliphatic

C ₆ - to C ₂ 2 "hydrocarbon radical, an optionally substituted and / or heteroatoms containing aromatic radical having 6 to 20 carbon atoms, with the proviso that at least one of the radicals is a opposite

Isocyanate groups is or contains reactive hydrogen atom

SO = styrene oxide residue,

EO = ethylene oxide radical, PO = propylene oxide radical,

BO = butylene oxide radical,

DTO = dodecene oxide,

TTO = tetradecenoxide, a = 0 to 3, b = 3 to 30, c = 0 to 5, d = 0 to 5, e = 0 to 5, f = 0 to 5,

with the proviso that (a + c + d + e + f) is £ b, and the reaction is continued until substantially no more NCO groups are present.

2. polyurethane thickener according to claim 1, character- ized in that in the preparation of a

Compound C) of the general formula (I) is used, in the

R ¹ = an optionally substituted and / or multiple bonds and / or hetero atoms containing aliphatic, cycloaliphatic hydrocarbon radical having 8 to 18 carbon atoms, and

R ² = hydrogen, a = 0 to 1, b = 5 to 15, c = 0 to 2, d = 0 to 2, e = 0 to 2 and f = 0.

3. polyurethane thickener according to claim 1, character- ized in that in the manufacture of a

Compound C) of the general formula (I) is used, in the

R ¹ = an optionally substituted and / or multiple bonds and / or heteroatoms retaining aliphatic, cycloaliphatic

Hydrocarbon radical with 8 to 18 C atoms

is.

4. polyurethane thickener according to claim 1, characterized in that in the preparation of a compound C) of the general formula (I) is used, in the

R ¹ = an optionally substituted and / or heteroatoms containing aromatic radical having 10 to 16 carbon atoms

is.

5. polyurethane thickener according to claim 1, characterized in that in the preparation of a compound C) of the general formula (I) is used, in the

R ² = a hydrogen radical, an optionally substituted and / or multiple bonds and / or heteroatoms containing aliphatic shear, cycloaliphatic hydrocarbon radical having 8 to 18 carbon atoms

is.

6. polyurethane thickener according to claim 1, characterized in that in the preparation of a compound C) of the general formula (I) is used, in the R ² = an optionally substituted and / or heteroatoms containing aromatic radical having 10 to 16 carbon atoms

is.

7. polyurethane thickener according to claim 1, since ^¬ characterized in that in the preparation of a compound C) of the general formula (I) is used, in the

R ¹ = a hydrogen radical, an optionally sub ^¬ stituted and / or multiple bonds, and / or heteroatom-containing of aliphatic, cycloaliphatic hydrocarbon radical having 8 to 18 carbon atoms, a ge ^¬ optionally substituted and / or heteroatom-containing aromatic radical having from 10 to 16 C atoms, and R ² = hydrogen

is.

8. Preparations containing a) from 10 to 50% by weight of a polyurethane thickener according to one of claims 1 to 5, b) from 0 to 50% by weight of an organic solvent, c) from 0 to 50% by weight an organic auxiliary surfactant; d) ad 100% by weight of water.

9. Use of polyurethane thickeners according to one of claims 1 to 7 for the adjustment of a) Newtonian, b) pseudoplastic and c) high-shear properties in aqueous systems.

10. Use of polyurethane thickeners according to any one of claims 1 to 7 for thickening defoamer emulsions.