EP1753847B1 - Lubricating grease having a high water-resistance - Google Patents

Description

The present invention relates to grease having high water resistance.

Greases are known per se and are widely used.
Greases, hereinafter also referred to as "fats", are solid to semi-liquid substances which are formed by dispersion of a thickening agent in a liquid lubricant. Other additives (additives) that impart special properties may be included.

The basic consistency of a fat is determined by the combination of base fluid and thickening agent. The base liquid is usually a base oil customary in the lubricant industry, e.g. Mineral oil, synthetic oil or vegetable oil.

As thickening agents are very often, but not exclusively, simple metal soaps used. Furthermore, but more rarely, complex metal soaps, organically modified clay (bentonite) or polyurea are used. Physically, the thickening agents form the solid phase of the dispersion and thus determine, in addition to the base oil, decisively the physical / mechanical properties of the grease, such as low-temperature behavior, water resistance, dropping point or oil separation behavior.
The different combinations of base oil and thickening agent are known to the expert and determine the range of application of the grease in technical application.

Recently, more polymers are used in addition to the known thickening agents. These cause in addition to an increase in the viscosity of Base oil (effect as a thickener) often also a change in the structure of the inorganic thickener (effect as a structure modifier).
The effect of polymers as thickeners or viscosity index improvers has long been established in the lubricant industry in base oils, for example mineral oils, synthetic oils or vegetable oils, and is the state of the art. However, the use of polymers and their action in fats is relatively new and has been proven only with a few examples from the literature.

US 3,476,532, Hartman, Nov. 4, 1969 describes metal-containing complexes of oxidized polyethylene containing functional oxygen groups, eg carbonyl, carboxyl, or hydroxy groups. The material can be used to make grease-like compositions. The composition consists of a mixture of oxidized polyethylene and a complexing agent selected from at least divalent metal salts, fatty acids and metal complexes.

U.S. 3,705,853, Fau et al., Sept. 23, 1970 describes a grease consisting of a paraffinic mineral oil, a calcium complex soap thickener and an organic terpolymer consisting of 65% ethylene, 5% ester comonomer and 0.01-3% acidic comonomer with a melt index between 0.5 and 200. The fats have better water resistance, measured by the water wash test according to ASTM D 1264.

U.S. 4,877,557, Kaneshige et al., Oct. 31, 1989 describes a lubricant composition containing a synthetic lubricating oil, a wear protection additive and a liquid, modified copolymer of ethylene and alpha-olefin having a number average molecular weight between 300 and 12,000 g / mol.

U.S. 5,116,522, Brown et al, Aug. 23, 1989 describes a lubricant composition consisting of ethylene copolymers, a lubricating oil, a thickener and a viscosity index improver. In this case, the ethylene copolymer is a polymer of isobutylene or a copolymer of ethylene, butylene, or isobutylene with a C3 to C30 olefin. As the viscosity index improver, copolymers consisting of 60-90% of ethylene and 40-10% of vinyl acetate, alkyl acrylates or alkyl methacrylates are used. The composition has very good high temperature adhesion and low temperature softening.

EP 806,469 and U.S. 5,858,934, Wiggins et al, May 8, 1996 describe an improved biodegradable grease composition from a natural base or synthetic triglyceride based base oil, a performance additive consisting of an alkylphenol, a benzotriazole or an aromatic amine, and a thickening agent comprising the reaction product of a metal based material and a carboxylic acid or its ester. In addition, the grease may also contain viscosity modifier, pour point improver or the combination of both.
The nature of the viscosity modifier or pour point improver will not be discussed.

US 6,300,288, Curtis et al., March 31, 1994 describes a grease consisting of an oil having a viscosity typical for a lubricant, an acid functional modified polymer consisting of an α-olefin / diene copolymer or a hydrogenated α-olefin / diene copolymer, a metallic species capable of interacting with the acid functionality of the polymer to achieve an association between the acid groups, and a co-thickener. The grease has improved rheological properties. The co-thickener and the metallic species can together form a thickened, overbased material, in the special case an overbased carboxylate. US 2,577,706 discloses a lubricant containing a major portion of a grease consisting essentially of a lubricating oil, the organic acid alkali metal salt as a thickener, and a small amount of polymeric compound sufficient to enhance the emulsification of the grease in water; Compound saponifiable repeat units selected from carboxyl and carboxylic acid ester groups, of which 10% to 60% are saponified by metals selected from alkali and alkaline earth metals.

In general, the use of non-functionalized, purely polyolefinic polymers is adequately described in the literature, for example for polyisobutylenes (PIBs) in Tribol. Lubrication piercing. (1995), 42 (2), 92-96 and for linear, branched and partially branched polyethylenes; isotactic polypropylenes, poly-1-butenes and poly (4-methyl-1-pentenes) in J. Synth. Lubric. 4 (1987 ).

The use of reactively modified copolymers based on olefin copolymers (OCPs) has hitherto been restricted to a few examples and is disclosed, inter alia, in US Pat NLGI Spokesman, Vol. 59, No 10, Feb 1999 described. The use of polyalkyl acrylates and polyalkyl methacrylates (PAMAs) as viscosity index improvers and pour point improvers is known in the literature and in the art ( Wilfried J. Bartz et al, greases, expert Verl., 2000, ISBN 3-8169-1533-7 . Wilfried J. Bartz et al. Additives for lubricants, expert Verl., 1994, ISBN 3-8169-0916-7 ).

According to the prior art set forth above, the addition of polymers to lubricating greases determines certain physical parameters, e.g. improved rheological properties or the water resistance of fats. On the other hand, it should be noted that there is a continuing need to further improve these properties. In particular, it is important to achieve a better property profile. In this case, the improvement of a property, such as the water resistance should not be associated with an excessive deterioration of other properties, such as handleability or homogeneity.

In particular, the greases should have a particularly high water resistance, an excellent consistency and a high homogeneity.

Another object may be seen to provide greases having improved temperature characteristics. In particular, the properties should be improved at low temperatures. Furthermore, the greases should be able to be used over a particularly wide temperature range.

Thus, it was an object of the present invention to provide a grease with a particularly high homogeneity.

Furthermore, the greases should be able to be produced inexpensively. Here, the production should be possible on an industrial scale without the need for new or structurally complex systems.

These and other objects which are not explicitly mentioned, but which are readily derivable or deducible from the contexts discussed hereinbelow, are solved by greases having all the features of patent claim 1. Advantageous modifications of the greases according to the invention are protected in the subclaims referring back to claim 1 , With regard to the method of manufacture and use, claims 10 and 13 provide a solution to the underlying problem.

1. a) 0 bis 40 Gew.-%, bezogen auf das Gewicht der Monomerenzusammensetzungen zur Herstellung der polymeren Strukturverbesserer, mindestens eines (Meth)acrylats der Formel (I)
   
   worin R Wasserstoff oder Methyl darstellt, R¹ einen linearen oder verzweigten Alkylrest mit 1 bis 5 Kohlenstoffatomen bedeutet,
2. b) 40 bis 99,99 Gew.-%, bezogen auf das Gewicht der Monomerenzusammensetzungen zur Herstellung der polymeren Strukturverbesserer, mindestens eines (Meth)acrylats der Formel (II)
   
   worin R Wasserstoff oder Methyl darstellt, R² einen linearen oder verzweigten Alkylrest mit 6 bis 30 Kohlenstoffatomen bedeutet,
3. c) 0,01 bis 5 Gew.-%, bezogen auf das Gewicht der Monomerenzusammensetzungen zur Herstellung der polymeren Strukturverbesserer, Säuregruppen umfassende Monomere, wobei mindestens ein Teil der Monomere gemäß Komponente c) mindestens eine Carboxylgruppe umfasst,
4. d) 0 bis 59,99 Gew.-%, bezogen auf das Gewicht der Monomerenzusammensetzungen zur Herstellung der polymeren Strukturverbesserer, Comonomer besteht, und das Schmierfett 0,1 bis 10 Gew. % polymerer Strukturverbesserer umfasst, gelingt es auf nicht ohne Weiteres vorhersehbare Weise Schmierfette zur Verfügung zu stellen, die verbesserte Eigenschaften aufweisen.

In that a grease comprising at least one thickening agent and at least one lubricating oil contains at least one polymeric structural improver which can be obtained by polymerisation of monomer compositions comprising

1. a) 0 to 40% by weight, based on the weight of the monomer compositions for the preparation of the polymeric structure improvers, of at least one (meth) acrylate of the formula (I)
   
   wherein R is hydrogen or methyl, R ^{1 is} a linear or branched alkyl radical having 1 to 5 carbon atoms,
2. b) from 40 to 99.99% by weight, based on the weight of the monomer compositions for the preparation of the polymeric structure improvers, of at least one (meth) acrylate of the formula (II)
   
   where R is hydrogen or methyl, R ^{2 is} a linear or branched alkyl radical having 6 to 30 carbon atoms,
3. c) from 0.01 to 5% by weight, based on the weight of the monomer compositions for the preparation of the polymeric structure improvers, of monomers comprising acid groups, where at least a portion of the monomers according to component c) comprises at least one carboxyl group,
4. d) 0 to 59.99 wt .-%, based on the weight of the monomer compositions for the preparation of the polymeric structure improver, comonomer, and the grease comprises 0.1 to 10 wt.% Of polymeric structure improvers, it is possible in a not easily predictable manner To provide greases having improved properties.

• ➢ Die erfindungsgemäßen Schmierfette weisen eine sehr hohe Wasserresistenz auf.
• ➢ Die erfindungsgemäßen Schmierfette zeigen eine gute Homogenität. Hierbei ist die Konsistenz des Schmierfetts in einem weiten Bereich einstellbar.
• ➢ Die erfindungsgemäßen Schmierfette weisen sehr gute Temperatureigenschaften auf. So können die erfindungsgemäßen Schmierfette über einen besonders breiten Temperaturbereich eingesetzt werden. Darüber hinaus sind die Eigenschaften bei tiefen Temperaturen hervorragend.
• ➢ Des Weiteren können die erfindungsgemäßen Schmierfette nachträglich durch Modifikation von bekannten Schmierfetten hergestellt werden, wobei einem bekannten Fett ein polymerer Strukturverbesserer zugegeben wird. Hierdurch können insbesondere hohe Lagerkosten vermieden werden. Des Weiteren kann auf Kundenwünsche schnell reagiert werden. Hierbei verändert sich die Konsistenz des Schmierfetts nur geringfügig, wohingegen die Wasserresistenz stark zunimmt.
• ➢ Die Schmierfette der vorliegenden Erfindung können besonders leicht und einfach hergestellt werden. Hierbei können übliche, großtechnische Anlagen eingesetzt werden.
• ➢ Des Weiteren können in den Verfahren zur Herstellung der Schmierfette insbesondere kommerziell erhältliche Komponenten eingesetzt werden.

At the same time can be achieved by the greases of the invention a number of other benefits. These include:

• ➢ The greases of the invention have a very high water resistance.
• ➢ The greases according to the invention show good homogeneity. Here, the consistency of the grease is adjustable in a wide range.
• ➢ The lubricating greases according to the invention have very good temperature properties. Thus, the greases according to the invention can be used over a particularly wide temperature range. In addition, the properties are excellent at low temperatures.
• ➢ Furthermore, the greases according to the invention can be prepared subsequently by modification of known greases, wherein a polymeric structure improver is added to a known grease. As a result, in particular high storage costs can be avoided. Furthermore, it can react quickly to customer requests. Here, the consistency of the grease changes only slightly, whereas the water resistance increases greatly.
• ➢ The greases of the present invention can be produced particularly easily and simply. Here, conventional, large-scale systems can be used.
• ➢ In addition, commercially available components can be used in particular in the processes for producing the lubricating greases.

The greases of the invention include polymeric structural improvers. These polymers generally result in an improvement in water resistance. It is believed that these polymers physico-chemical interaction with the thickening agents, for example the Soap molecules enter, without this being a limitation.

worin R Wasserstoff oder Methyl darstellt, R¹ einen linearen oder verzweigten Alkylrest mit 1 bis 5 Kohlenstoffatomen bedeutet.Mixtures from which the polymeric structure improvers are obtainable may contain 0 to 40% by weight, especially 0.5 to 20% by weight, based on the weight of the monomer compositions for the preparation of the polymeric structure improvers, of at least one (meth) acrylate of the formula (I) included

wherein R represents hydrogen or methyl, R ^{1 represents} a linear or branched alkyl radical having 1 to 5 carbon atoms.

The term (meth) acrylates include methacrylates and acrylates as well as mixtures of both. These monomers are well known. Here, the alkyl radical may be linear, cyclic or branched.

Examples of component a) include (meth) acrylates derived from saturated alcohols, such as methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n Butyl (meth) acrylate, tert-butyl (meth) acrylate and pentyl (meth) acrylate;
Cycloalkyl (meth) acrylates such as cyclopentyl (meth) acrylate;
(Meth) acrylates derived from unsaturated alcohols, such as 2-propynyl (meth) acrylate, allyl (meth) acrylate and vinyl (meth) acrylate.

worin R Wasserstoff oder Methyl darstellt, R² einen linearen oder verzweigten Alkylrest mit 6 bis 30 Kohlenstoffatomen bedeutet.As a further constituent, the compositions to be polymerized for the preparation of preferred polymeric structural improvers contain from 40 to 99.99% by weight, in particular 55 to 95% by weight, based on the weight of the monomer compositions for the preparation of the polymeric structure improvers, of at least one (meth) acrylate of the formula (II)

wherein R represents hydrogen or methyl, R ^{2 represents} a linear or branched alkyl radical having 6 to 30 carbon atoms.

These include, among others
(Meth) acrylates derived from saturated alcohols, such as hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (meth) acrylate, 2-tert-butylheptyl (meth) acrylate, octyl (meth) acrylate, 3-iso-propylheptyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, 5-methylundecyl (meth) acrylate, dodecyl (meth) acrylate, 2-methyldodecyl (meth) acrylate, Tridecyl (meth) acrylate, 5-methyltridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, 2-methylhexadecyl (meth) acrylate, heptadecyl (meth) acrylate, 5-iso Propylheptadecyl (meth) acrylate, 4-tert-butyloctadecyl (meth) acrylate, 5-ethyloctadecyl (meth) acrylate, 3-iso-propyloctadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth ) acrylate, cetyleicosyl (meth) acrylate, stearyl eicosyl (meth) acrylate, docosyl (meth) acrylate and / or eicosyl tetratriacontyl (meth) acrylate;
Cycloalkyl (meth) acrylates such as 2,4,5-tri-t-butyl-3-vinylcyclohexyl (meth) acrylate, 2,3,4,5-tetra-t-butylcyclohexyl (meth) acrylate;
(Meth) acrylates derived from unsaturated alcohols, such as. For example, oleyl (meth) acrylate;
Cycloalkyl (meth) acrylates, such as 3-vinylcyclohexyl (meth) acrylate, cyclohexyl (meth) acrylate, bornyl (meth) acrylate.

The (meth) acrylates with a long-chain alcohol radical, in particular the compounds according to component (b), can be, for example, by Reacting of (meth) acrylates and / or the corresponding acids with long-chain fatty alcohols obtained, which generally produces a mixture of esters, such as (meth) acrylates with different long-chain alcohol residues. These fatty alcohols include Oxo Alcohol® 7911 and Oxo Alcohol® 7900, Oxo Alcohol® 1100 from Monsanto; Alphanol® 79 from ICI; Nafol® 1620, Alfol® 610 and Alfol® 810 from Sasol; Epal® 610 and Epal® 810 from Ethyl Corporation; Linevol® 79, Linevol® 911 and Dobanol® 25L from Shell AG; Lial 125 from Sasol; Dehydad® and Lorol® grades from Cognis.

According to a particular aspect of the present invention, the mixture for preparing preferred polymeric structural improvers comprises at least 60% by weight, preferably at least 70% by weight, based on the weight of the monomer compositions for the preparation of the polymeric structure improvers, of monomers of formula (II).

In general, the methacrylates are preferred over the acrylates.

According to a particular aspect of the present invention, preference is given to using mixtures of long-chain alkyl (meth) acrylates according to component b), the mixtures comprising at least one (meth) acrylate having 6 to 15 carbon atoms in the alcohol radical and at least one (meth) acrylate having 16 to 30 Have carbon atoms in the alcohol radical. Preferably, the proportion of the (meth) acrylates having 6 to 15 carbon atoms in the alcohol moiety is in the range of 20 to 95 wt .-%, based on the weight of the monomer composition for the preparation of the polymeric structure improvers. The proportion of (meth) acrylates having 16 to 30 carbon atoms in the alcohol residue is preferably in the range of 0.5 to 60 wt .-%, based on the weight of the monomer composition for the preparation of the polymeric structure improvers.

Component c) of the composition to be used for the preparation of preferred polymeric structure improvers comprises, in particular, monomers comprising acid groups or salts thereof.

Preferred salts are, in particular, the alkali metal salts, such as, for example, the lithium, sodium and / or potassium salts; the alkaline earth metal salts, such as the calcium and / or barium salts, as well as the aluminum salts and the ammonium salts.

The proportion of components c) is generally 0.01 to 5 wt .-%, preferably 0.1 to 5 wt .-% and particularly preferably 0.5 to 5 wt .-%, based on the weight of the monomer compositions for the preparation the polymeric structural improver.

worin R³ und R⁴ unabhängig ausgewählt sind aus der Gruppe bestehend aus Wasserstoff, Halogene, CN, lineare oder verzweigte Alkylgruppen mit 1 bis 20, vorzugsweise 1 bis 6 und besonders bevorzugt 1 bis 4 Kohlenstoffatomen, welche mit 1 bis (2n+1) Halogenatomen substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Alkylgruppe ist (beispielsweise CF₃), α, β-ungesättigte lineare oder verzweigte Alkenyl- oder Alkynylgruppen mit 2 bis 10, vorzugsweise von 2 bis 6 und besonders bevorzugt von 2 bis 4 Kohlenstoffatomen, welche mit 1 bis (2n-1) Halogenatomen, vorzugsweise Chlor, substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Alkylgruppe, beispielsweise CH₂=CCl-, ist, Cycloalkylgruppen mit 3 bis 8 Kohlenstoffatomen, welche mit 1 bis (2n-1) Halogenatomen, vorzugsweise Chlor, substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Cycloalkylgruppe ist; Arylgruppen mit 6 bis 24 Kohlenstoffatomen, welche mit 1 bis (2n-1) Halogenatomen, vorzugsweise Chlor, und/oder Alkylgruppen mit 1 bis 6 Kohlenstoffatomen substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Arylgruppe ist; COOR⁷, worin R⁷ unabhängig Wasserstoff, ein Alkalimetall, ein Erdalkalimetall und/oder Aluminium, eine Ammoniumgruppe mit bis zu 20 Kohlenstoffatomen oder eine Alkylgruppe mit 1 bis 40 Kohlenstoffatomen ist;
R⁵ und R⁶ unabhängig ausgewählt aus der Gruppe bestehend aus Wasserstoff, Halogen (vorzugsweise Fluor oder Chlor), Alkylgruppen mit 1 bis 6 Kohlenstoffatomen und COOR⁷, worin R⁷ unabhängig Wasserstoff, ein Alkalimetall, eine Ammoniumgruppe mit bis zu 20 Kohlenstoffatomen oder eine Alkylgruppe mit 1 bis 40 Kohlenstoffatomen ist worin R⁷ Wasserstoff, ein ein Alkalimetall, ein Erdalkalimetall und/oder Aluminium oder eine Alkylgruppe mit 1 bis 40 Kohlenstoffatomen ist, sind, oder R⁵ und R⁶ können zusammen eine Gruppe der Formel (CH₂)_n' bilden, welche mit 1 bis 2n' Halogenatomen oder C₁ bis C₄ Alkylgruppen substituiert sein kann, oder der Formel C(=O)-Y-C(=O) bilden, wobei n' von 2 bis 6, vorzugsweise 3 oder 4 ist und Y NR⁸, S oder O, vorzugsweise O sein kann, wobei R⁸ Wasserstoff, lineare oder verzweigte Alkyl-oder Arylgruppen mit 1 bis 20 Kohlenstoffatomen ist; wobei zumindest 2 der Reste R³, R⁴, R⁵ und R⁶ Wasserstoff oder Halogen sind und mindestens einer der Reste R³, R⁴, R⁵ und R⁶ mindestens eine Gruppe der Formel -COOM, , worin M Wasserstoff darstellt, umfasst.Acid group-containing monomers are known in the art. These can often be represented by the formula (III)

in which R ³ and R ^{4 are} independently selected from the group consisting of hydrogen, halogens, CN, linear or branched alkyl groups having 1 to 20, preferably 1 to 6 and particularly preferably 1 to 4 carbon atoms, which have 1 to (2n + 1) Halogen atoms, where n is the number of carbon atoms of the alkyl group (for example CF ₃ ), α, β-unsaturated linear or branched alkenyl or alkynyl groups having 2 to 10, preferably from 2 to 6 and particularly preferably from 2 to 4 carbon atoms which may be substituted with 1 to (2n-1) halogen atoms, preferably chlorine, where n is the number of carbon atoms of the alkyl group, for example CH ₂ = CCl-, cycloalkyl groups having 3 to 8 carbon atoms, which are substituted with 1 to (2n 1) halogen atoms, preferably chlorine, may be substituted, where n is the number of carbon atoms of the Cycloalkyl group; Aryl groups of 6 to 24 carbon atoms which may be substituted with 1 to (2n-1) halogen atoms, preferably chlorine, and / or alkyl groups of 1 to 6 carbon atoms, where n is the number of carbon atoms of the aryl group; COOR ⁷ , wherein R ^{7 is} independently hydrogen, an alkali metal, an alkaline earth metal and / or aluminum, an ammonium group having up to 20 carbon atoms or an alkyl group having 1 to 40 carbon atoms;
R ⁵ and R ^{6 are} independently selected from the group consisting of hydrogen, halogen (preferably fluoro or chloro), alkyl groups of 1 to 6 carbon atoms, and COOR ⁷ wherein R ^{7 is} independently hydrogen, an alkali metal, an ammonium group of up to 20 carbon atoms, or a Wherein R ^{7 is} hydrogen, an alkali metal, an alkaline earth metal and / or aluminum or an alkyl group having from 1 to 40 carbon atoms, or R ⁵ and R ⁶ may together represent a group of the formula (CH ₂ ) _{n '} , which may be substituted by 1 to 2n' halogen atoms or C ₁ to C ₄ alkyl groups, or of the formula C (= O) -YC (= O), where n 'is from 2 to 6, preferably 3 or 4 and Y may be NR ⁸ , S or O, preferably O, wherein R ^{8 is} hydrogen, linear or branched alkyl or aryl groups of 1 to 20 carbon atoms; where at least 2 of the radicals R ³ , R ⁴ , R ⁵ and R ^{6 are} hydrogen or halogen and at least one of the radicals R ³ , R ⁴ , R ⁵ and R ^{6 is} at least one group of the formula -COOM, in which M is hydrogen, includes.

These compounds can generally be copolymerized with the monomers according to component a), b) and d). These include, inter alia, ethylenically unsaturated compounds such as vinylsulfonic acid, vinylphosphonic acid, acrylic acid, methacrylic acid, fumaric acid, monoesters of fumaric acid, wherein the alcohol radical may generally comprise 1 to 30 carbon atoms, maleic acid, monoesters of maleic acid, the alcohol radical being generally 1 to 30 Carbon atoms, vinyl benzoic acid and sulfonated styrenes such as styrenesulfonic acid. Furthermore, the from salts derived from these acids, in particular the alkali metal, alkaline earth metal and / or aluminum salts.

Component d) of the composition to be used for the preparation of preferred polymeric structure improvers comprises, in particular, ethylenically unsaturated monomers which can be copolymerized with the monomers according to components a) to c).

worin R^1* und R^2* unabhängig ausgewählt sind aus der Gruppe bestehend aus Wasserstoff, Halogene, CN, lineare oder verzweigte Alkylgruppen mit 1 bis 20, vorzugsweise 1 bis 6 und besonders bevorzugt 1 bis 4 Kohlenstoffatomen, welche mit 1 bis (2n+1) Halogenatomen substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Alkylgruppe ist (beispielsweise CF₃), α, β-ungesättigte lineare oder verzweigte Alkenyl- oder Alkynylgruppen mit 2 bis 10, vorzugsweise von 2 bis 6 und besonders bevorzugt von 2 bis 4 Kohlenstoffatomen, welche mit 1 bis (2n-1) Halogenatomen, vorzugsweise Chlor, substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Alkylgruppe, beispielsweise CH₂=CCl-, ist, Cycloalkylgruppen mit 3 bis 8 Kohlenstoffatomen, welche mit 1 bis (2n-1) Halogenatomen, vorzugsweise Chlor, substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Cycloalkylgruppe ist; Arylgruppen mit 6 bis 24 Kohlenstoffatomen, welche mit 1 bis (2n-1) Halogenatomen, vorzugsweise Chlor, und/oder Alkylgruppen mit 1 bis 6 Kohlenstoffatomen substituiert sein können, wobei n die Zahl der Kohlenstoffatome der Arylgruppe ist; COOR^9*, worin R^9* eine Alkylgruppe mit 1 bis 40 Kohlenstoffatomen ist; C(=Y*)R^5*, C(=Y*)NR^6*R^7*, Y*C(=Y*)R^5*, SOR^5*, SO₂R^5*, OSO₂R^5*, NR^8*SO₂R^5*, PR^5* ₂, P(=Y*)R^5* ₂, Y*PR^5* ₂, Y*P(=Y*)R^5* ₂, NR^8* ₂ welche mit einer zusätzlichen R^8*-, Aryl- oder Heterocyclyl-Gruppe quaternärisiert sein kann, wobei Y* NR^8*, S oder O, vorzugsweise O sein kann; R^5* eine Alkylgruppe mit 1 bis 20 Kohlenstoffatomen, eine Alkylthio mit 1 bis 20 Kohlenstoffatomen, OR^10* (R^10* ist Wasserstoff oder ein Alkalimetall), Alkoxy von 1 bis 20 Kohlenstoffatomen, Aryloxy oder Heterocyklyloxy ist; R^6* und R^7* unabhängig Wasserstoff oder eine Alkylgruppe mit 1 bis 20 Kohlenstoffatomen sind, oder R^6* und R^7* können zusammen eine Alkylengruppe mit 2 bis 7 vorzugsweise 2 bis 5 Kohlenstoffatomen bilden, wobei sie einen 3 bis 8-gliedrigen, vorzugsweise 3 bis 6-gliedrigen Ring bilden, und R^8* Wasserstoff, lineare oder verzweigte Alkyl- oder Arylgruppen mit 1 bis 20 Kohlenstoffatomen sind;
R^3* und R^4* unabhängig ausgewählt aus der Gruppe bestehend aus Wasserstoff, Halogen (vorzugsweise Fluor oder Chlor), Alkylgruppen mit 1 bis 6 Kohlenstoffatomen und COOR^9*, worin R^9* eine Alkylgruppe mit 1 bis 40 Kohlenstoffatomen ist, sind, oder R^3* und R^4* können zusammen eine Gruppe der Formel (CH₂)_n' bilden, welche mit 1 bis 2n' Halogenatomen oder C₁ bis C₄ Alkylgruppen substituiert sein kann, oder der Formel C(=O)-Y*-C(=O) bilden, wobei n' von 2 bis 6, vorzugsweise 3 oder 4 ist und Y* wie zuvor definiert ist; und wobei zumindest 2 der Reste R^1*, R^2*, R^3* und R^4* Wasserstoff oder Halogen sind.However, comonomers are particularly suitable for the polymerization according to the present invention, which correspond to the formula:

wherein R ^{1 *} and R ^{2 * are} independently selected from the group consisting of hydrogen, halogens, CN, linear or branched alkyl groups having 1 to 20, preferably 1 to 6 and particularly preferably 1 to 4 carbon atoms, which are substituted with 1 to (2n + 1) halogen atoms may be substituted, wherein n is the number of carbon atoms of the alkyl group (for example CF ₃ ), α, β-unsaturated linear or branched alkenyl or alkynyl groups having 2 to 10, preferably from 2 to 6 and particularly preferably from 2 to 4 carbon atoms, which may be substituted with 1 to (2n-1) halogen atoms, preferably chlorine, wherein n is the number of carbon atoms of the alkyl group, for example CH ₂ = CCl-, cycloalkyl groups having 3 to 8 carbon atoms, which is 1 to (2n-1) halogen atoms, preferably chlorine, may be substituted, wherein n is the number of carbon atoms of the cycloalkyl group; Aryl groups of 6 to 24 carbon atoms which may be substituted with 1 to (2n-1) halogen atoms, preferably chlorine, and / or alkyl groups of 1 to 6 carbon atoms, where n is the number of carbon atoms of the aryl group; COOR ^{9 *} , where R ^{9 * is} an alkyl group with 1 to 40 carbon atoms; C (= Y *) R ^{5 *} , C (= Y *) NR ^{6 *} R ^{7 *} , Y * C (= Y *) R ^{5 *} , SOR ^{5 *} , SO ₂ R ^{5 *} , OSO ₂ R ^{5 *} , NR ^{8 *} SO ₂ R ^{5 *} , PR ^{5 *} ₂ , P (= Y *) R ^{5 *} ₂ , Y * PR ^{5 *} ₂ , Y * P (= Y *) R ^{5 *} ₂ , NR ^{8 *} ₂ which may be quaternized with an additional R ^{8 *} , aryl or heterocyclyl group, where Y * NR ^{8 *} , S or O, preferably O; R ^{5 * is} an alkyl group having 1 to 20 carbon atoms, an alkylthio having 1 to 20 carbon atoms, OR ^{10 *} (R ^{10 *} is hydrogen or an alkali metal), alkoxy of 1 to 20 carbon atoms, aryloxy or heterocyclyloxy; R ^{6 *} and R ^{7 * are} independently hydrogen or an alkyl group having 1 to 20 carbon atoms, or R ^{6 *} and R ^{7 *} may together form an alkylene group having 2 to 7, preferably 2 to 5, carbon atoms, having a 3 to 8 membered one , preferably 3 to 6 membered ring, and R ^{8 * are} hydrogen, linear or branched alkyl or aryl groups of 1 to 20 carbon atoms;
R ^{3 *} and R ^{4 * are} independently selected from the group consisting of hydrogen, halogen (preferably fluoro or chloro), alkyl groups of 1 to 6 carbon atoms, and COOR ^{9 *} where R ^{9 * is} an alkyl group of 1 to 40 carbon atoms; or R ^{3 *} and R ^{4 *} may together form a group of the formula (CH ₂ ) _{n '} , which may be substituted by 1 to 2n' halogen atoms or C ₁ to C ₄ alkyl groups, or the formula C (= O) -Y Form * -C (= O) where n 'is from 2 to 6, preferably 3 or 4, and Y * is as previously defined; and wherein at least 2 of the radicals R ^{1 *} , R ^{2 *} , R ^{3 *} and R ^{4 * are} hydrogen or halogen.

• Aryl(meth)acrylate, wie Benzylmethacrylat oder
• Phenylmethacrylat, wobei die Arylreste jeweils unsubstituiert oder bis zu vierfach substituiert sein können;
• Methacrylate von halogenierten Alkoholen, wie
• 2,3-Dibromopropylmethacrylat,
• 4-Bromophenylmethacrylat,
• 1,3-Dichloro-2-propylmethacrylat,
• 2-Bromoethylmethacrylat,
• 2-Iodoethylmethacrylat,
• Chloromethylmethacrylat;
• Vinylhalogenide, wie beispielsweise Vinylchlorid, Vinylfluorid, Vinylidenchlorid und Vinylidenfluorid;
• Vinylester, wie Vinylacetat;
• Styrol, substituierte Styrole mit einem Alkylsubstituenten in der Seitenkette, wie z. B. α-Methylstyrol und α-Ethylstyrol, substituierte Styrole mit einem Alkylsubstitutenten am Ring, wie Vinyltuluol und p-Methylstyrol, halogenierte Styrole, wie beispielsweise Monochlorstyrole, Dichlorstyrole, Tribromstyrole und Tetrabromstyrole;
• Heterocyclische Vinylverbindungen, wie 2-Vinylpyridin, 3-Vinylpyridin, 2-Methyl-5-vinylpyridin, 3-Ethyl-4-vinylpyridin, 2,3-Dimethyl-5-vinylpyridin, Vinylpyrimidin, Vinylpiperidin, 9-Vinylcarbazol, 3-Vinylcarbazol, 4-Vinylcarbazol, 1-Vinylimidazol, 2-Methyl-1-vinylimidazol, N-Vinylpyrrolidon, 2-Vinylpyrrolidon, N-Vinylpyrrolidin, 3-Vinylpyrrolidin, N-Vinylcaprolactam, N-Vinylbutyrolactam, Vinyloxolan, Vinylfuran, Vinylthiophen, Vinylthiolan, Vinylthiazole und hydrierte Vinylthiazole, Vinyloxazole und hydrierte Vinyloxazole;
• Vinyl- und Isoprenylether;
• Maleinsäurederivate, wie beispielsweise die Diester der Maleinsäure, wobei der Alkoholrest im allgemeinen 1 bis 30 Kohlenstoffatome umfassen kann, Maleinsäureanhydrid, Methylmaleinsäureanhydrid, Maleinimid, Methylmaleinimid;
• Fumarsäurederivate, wie beispielsweise die Diester der Fumarsäure, wobei der Alkoholrest im allgemeinen 1 bis 30 Kohlenstoffatome umfassen kann;
• Diene wie beispielsweise Divinylbenzol.

These include:

• Aryl (meth) acrylates, such as benzyl methacrylate or
• Phenyl methacrylate, wherein the aryl radicals may each be unsubstituted or substituted up to four times;
• Methacrylates of halogenated alcohols, such as
• 2,3-Dibromopropylmethacrylat,
• 4-Bromophenylmethacrylat,
• 1,3-dichloro-2-propyl,
• 2-Bromoethylmethacrylat,
• 2-Iodoethylmethacrylat,
• Chloromethylmethacrylat;
• Vinyl halides such as vinyl chloride, vinyl fluoride, vinylidene chloride and vinylidene fluoride;
• Vinyl esters, such as vinyl acetate;
• Styrene, substituted styrenes having an alkyl substituent in the side chain, such as. Α-methylstyrene and α-ethylstyrene, substituted styrenes having an alkyl substituent on the ring such as vinyltoluene and p-methylstyrene, halogenated styrenes such as monochlorostyrenes, dichlorostyrenes, tribromostyrenes and tetrabromostyrenes;
• Heterocyclic vinyl compounds, such as 2-vinylpyridine, 3-vinylpyridine, 2-methyl-5-vinylpyridine, 3-ethyl-4-vinylpyridine, 2,3-dimethyl-5-vinylpyridine, vinylpyrimidine, vinylpiperidine, 9-vinylcarbazole, 3-vinylcarbazole, 4-vinylcarbazole, 1-vinylimidazole, 2-methyl-1-vinylimidazole, N-vinylpyrrolidone, 2-vinylpyrrolidone, N-vinylpyrrolidine, 3-vinylpyrrolidine, N-vinylcaprolactam, N-vinylbutyrolactam, vinyloxolane, vinylfuran, vinylthiophene, vinylthiolane, vinylthiazoles and hydrogenated vinylthiazoles, vinyloxazoles and hydrogenated vinyloxazoles;
• Vinyl and isoprenyl ethers;
• Maleic acid derivatives, such as the diesters of maleic acid, wherein the alcohol residue may generally comprise from 1 to 30 carbon atoms, maleic anhydride, methylmaleic anhydride, maleimide, methylmaleimide;
• Fumaric acid derivatives, such as the diesters of fumaric acid, wherein the alcohol residue may generally comprise from 1 to 30 carbon atoms;
• Dienes such as divinylbenzene.

worin R unabhängig Wasserstoff oder Methyl, R⁹ unabhängig eine 2 bis 1000 Kohlenstoffatome umfassende Gruppe mit mindestens einem Heteroatom, X unabhängig ein Schwefel- oder Sauerstoffatom oder eine Gruppe der Formel NR¹⁰, worin R¹⁰ unabhängig Wasserstoff oder eine Gruppe mit 1 bis 20 Kohlenstoffatomen und n eine ganze Zahl größer oder gleich 3 darstellt.With particular preference the compositions for preparing preferred structure improvers comprise comonomers according to component d) which can be represented by the formula (IV),

wherein R is independently hydrogen or methyl, R ^{9 is} independently a 2 to 1000 carbon group comprising at least one heteroatom, X is independently a sulfur or oxygen atom or a group of formula NR ¹⁰ , wherein R ^{10 is} independently hydrogen or a group of 1 to 20 carbon atoms and n represents an integer greater than or equal to 3.

The radical R ⁹ represents a group comprising 2 to 1000, in particular 2 to 100, preferably 2 to 20 carbon atoms. The term "2 to 1000 carbon group" denotes radicals of organic compounds having 2 to 1000 carbon atoms. It includes aromatic and heteroaromatic groups as well as alkyl, cycloalkyl, alkoxy, cycloalkoxy, alkenyl, alkanoyl, alkoxycarbonyl and heteroaliphatic groups. The groups mentioned can be branched or unbranched. Furthermore, these groups may have conventional substituents. Substituents are, for example, linear and branched alkyl groups having 1 to 6 carbon atoms, such as, for example, methyl, ethyl, propyl, butyl, pentyl, 2-methylbutyl or hexyl; Cycloalkyl groups such as cyclopentyl and cyclohexyl; aromatic groups, such as phenyl or naphthyl; Amino groups, ether groups, ester groups and halides.

According to the invention, aromatic groups are radicals of mononuclear or polynuclear aromatic compounds having preferably 6 to 20, in particular 6 to 12, carbon atoms. Heteroaromatic groups denote aryl radicals in which at least one CH group has been replaced by N and / or at least two adjacent CH groups have been replaced by S, NH or O, heteroaromatic groups having from 3 to 19 carbon atoms.

Preferred aromatic or heteroaromatic groups according to the invention are derived from benzene, naphthalene, biphenyl, diphenyl ether, diphenylmethane, diphenyldimethylmethane, bisphenone, diphenylsulfone, thiophene, furan, pyrrole, thiazole, oxazole, imidazole, isothiazole, isoxazole, pyrazole, 1,3,4-oxadiazole , 2,5-diphenyl-1,3,4-oxadiazole, 1,3,4-thiadiazole, 1,3,4-triazole, 2,5-diphenyl-1,3,4-triazole, 1,2,5 -Triphenyl-1,3,4-triazole, 1,2,4-oxadiazole, 1,2,4-thiadiazole, 1,2,4-triazole, 1,2,3-triazole, 1,2,3,4 Tetrazole, benzo [b] thiophene, benzo [b] furan, indole, benzo [c] thiophene, benzo [c] furan, isoindole, benzoxazole, benzothiazole, benzimidazole, benzisoxazole, benzisothiazole, benzopyrazole, benzothiadiazole, benzotriazole, dibenzofuran, dibenzothiophene , Carbazole, pyridine, bipyridine, pyrazine, pyrazole, pyrimidine, pyridazine, 1,3,5-triazine, 1,2,4-triazine, 1,2,4,5-triazine, tetrazine, quinoline, isoquinoline, quinoxaline, quinazoline , Cinnoline, 1,8-naphthyridine, 1,5-naphthyridine, 1,6-naphthyridine, 1,7-naphthyridine, phthalazine , Pyridopyrimidine, purine, pteridine or quinolizine, 4H-quinolizine, diphenyl ether, anthracene, benzopyrrole, benzooxathiadiazole, benzooxadiazole, benzopyridine, benzopyrazine, benzopyrazidine, benzopyrimidine, benzotriazine, indolizine, pyridopyridine, imidazopyrimidine, pyrazinopyrimidine, carbazole, aciridine, phenazine, benzoquinoline, phenoxazine , Phenothiazine, acridizine, benzopteridine, phenanthroline and phenanthrene, which may optionally be substituted.

The preferred alkyl groups include the methyl, ethyl, propyl, isopropyl, 1-butyl, 2-butyl, 2-methylpropyl, tert-butyl, pentyl, 2-methylbutyl, 1,1- Dimethylpropyl, hexyl, heptyl, octyl, 1,1,3,3-tetramethylbutyl, nonyl, 1-decyl, 2-decyl, undecyl, dodecyl, pentadecyl and the eicosyl group.

Preferred cycloalkyl groups include the cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups, optionally substituted with branched or unbranched alkyl groups.

Preferred alkenyl groups include the vinyl, allyl, 2-methyl-2-propene, 2-butenyl, 2-pentenyl, 2-decenyl and 2-eicosenyl groups.

The preferred alkynyl groups include the ethynyl, propargyl, 2-methyl-2-propyne, 2-butynyl, 2-pentynyl and 2-decynyl groups.

Preferred alkanoyl groups include the formyl, acetyl, propionyl, 2-methylpropionyl, butyryl, valeroyl, pivaloyl, hexanoyl, decanoyl and dodecanoyl groups.

The preferred alkoxycarbonyl groups include the methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, tert-butoxycarbonyl, hexyloxycarbonyl, 2-methylhexyloxycarbonyl, decyloxycarbonyl or dodecyloxycarbonyl group.

The preferred alkoxy groups include alkoxy groups whose hydrocarbon radical is one of the aforementioned preferred alkyl groups.

Preferred cycloalkoxy groups include cycloalkoxy groups whose hydrocarbon radical is one of the aforementioned preferred cycloalkyl groups.

The preferred heteroatoms contained in R ¹⁰ include, among others, oxygen, nitrogen, sulfur, boron, silicon and phosphorus.

According to a particular embodiment of the present invention, the radical R ⁸ in formula (IV) has at least one group of the formula -OH or -NR ¹⁰ R ¹⁰ , in which R ¹⁰ independently comprises hydrogen or a group having 1 to 20 carbon atoms.

Preferably, the group X in formula (IV) can be represented by the formula NH.

The number ratio of heteroatoms to carbon atoms in the radical R ^{9 of} the formula (IV) can be within a wide range. This ratio is preferably in the range from 1: 1 to 1:10, in particular 1: 1 to 1: 5 and particularly preferably 1: 2 to 1: 4.

The residue R ^{9 of} the formula (IV) comprises 2 to 1000 carbon atoms. In a particular aspect, R ^{9 has} at most 10 carbon atoms.

The particularly preferred comonomers include, inter alia, hydroxyalkyl (meth) acrylates, such as
3-hydroxypropyl methacrylate,
3,4-dihydroxybutyl,
2-hydroxyethyl methacrylate,
2-hydroxypropyl methacrylate,
2,5-dimethyl-1,6-hexanediol (meth) acrylate,
1,10-decanediol (meth) acrylate;
carbonyl-containing methacrylates, such as
2-carboxyethyl methacrylate,
Carboxymethylmethacrylat,
oxazolidinylethyl,
N- (methacryloyloxy) formamide,
Acetonylmethacrylat,
N-methacryloylmorpholine,
N-methacryloyl-2-pyrrolidinone,
N- (2-methacryloyloxyethyl) -2-pyrrolidinone,
N- (3-methacryloyloxypropyl) -2-pyrrolidinone,
N- (2-Methacryloyloxypentadecyl) -2-pyrrolidinone,
N- (3-Methacryloyloxyheptadecyl) -2-pyrrolidinone,
Glycol dimethacrylates, such as 1,4-butanediol methacrylate, 2-butoxyethyl methacrylate, 2-ethoxyethoxymethyl methacrylate,
2-ethoxyethyl;
Methacrylates of ether alcohols, such as
tetrahydrofurfuryl,
Vinyloxyethoxyethylmethacrylat,
methoxyethoxyethyl,
1-Butoxypropylmethacrylat,
1-methyl- (2-vinyloxy) ethyl methacrylate,
Cyclohexyloxymethylmethacrylat,
Methoxymethoxyethylmethacrylat,
Benzyloxymethyl methacrylate,
furfuryl,
2-butoxyethyl methacrylate,
2-Ethoxyethoxymethylmethacrylat,
2-ethoxyethyl methacrylate,
Allyloxymethylmethacrylat,
1-ethoxybutyl methacrylate,
methoxymethyl,
1-ethoxyethyl methacrylate,
Ethoxymethyl methacrylate and ethoxylated (meth) acrylates which preferably have 1 to 20, in particular 2 to 8, ethoxy groups;
Aminoalkyl (meth) acrylates and aminoalkyl (meth) acrylatamides, such as
N- (3-dimethylaminopropyl) methacrylamide,
dimethylaminopropyl,
3-Diethylaminopentylmethacrylat,
3-Dibutylaminohexadecyl (meth) acrylate;
Nitriles of (meth) acrylic acid and other nitrogen-containing methacrylates, such as
N- (methacryloyloxyethyl) diisobutylketimin,
N- (methacryloyloxyethyl) dihexadecylketimin,
methacryloylamidoacetonitrile,
2-Methacryloyloxyethylmethylcyanamid,
cyanomethyl;
heterocyclic (meth) acrylates, such as 2- (1-imidazolyl) ethyl (meth) acrylate,
2- (4-morpholinyl) ethyl (meth) acrylate and 1- (2-methacryloyloxyethyl) -2-pyrrolidone;
Oxiranyl methacrylates, as
2,3-epoxybutyl methacrylate,
3,4-epoxybutyl,
10,11-epoxyundecyl methacrylate,
2,3-epoxycyclohexyl methacrylate,
10,11-Epoxyhexadecylmethacrylat ;;
glycidyl methacrylate;
Sulfur-containing methacrylates, such as
Ethylsulfinylethylmethacrylat,
4-Thiocyanatobutylmethacrylat,
Ethylsulfonylethylmethacrylat,
Thiocyanatomethylmethacrylat,
Methylsulfinylmethylmethacrylat,
sulfide bis (methacryloyloxyethyl);
Phosphorus, boron and / or silicon-containing methacrylates, such as
2- (Dimethylphosphato) propyl methacrylate,
2- (Ethylenphosphito) propyl methacrylate,
Dimethylphosphinomethylmethacrylat,
Dimethylphosphonoethylmethacrylat,
Diethylmethacryloylphosphonat,
Dipropylmethacryloyl phosphate, 2- (dibutylphosphono) ethyl methacrylate,
2,3-Butylenmethacryloylethylborat,
Methyldiethoxymethacryloylethoxysilan,
Diethylphosphatoethylmethacrylat.

These monomers can be used singly or as a mixture.

The ethoxylated (meth) acrylates can be obtained, for example, by transesterification of alkyl (meth) acrylates with ethoxylated alcohols, which more preferably have from 1 to 20, in particular from 2 to 8, ethoxy groups. The hydrophobic radical of the ethoxylated alcohols may preferably comprise 1 to 40, in particular 4 to 22, carbon atoms, it being possible to use both linear and branched alcohol radicals. According to a further preferred embodiment, the ethoxylated (meth) acrylates have an OH end group.

Examples of commercially available ethoxylates which can be used for the preparation of ethoxylated (meth) acrylates are ethers of the Lutensol® A brands, in particular Lutensol® A 3 N, Lutensol® A 4 N, Lutensol® A 7 N and Lutensol® A 8 N, ethers of the Lutensol® TO brands, in particular Lutensol® TO 2, Lutensol® TO 3, Lutensol® TO 5, Lutensol® TO 6, Lutensol® TO 65, Lutensol® TO 69, Lutensol® TO 7, Lutensol® TO 79 , Lutensol® 8 and Lutensol® 89, ethers of the Lutensol® AO brands, in particular Lutensol® AO 3, Lutensol® AO 4, Lutensol® AO 5, Lutensol® AO 6, Lutensol® AO 7, Lutensol® AO 79, Lutensol® AO 8 and Lutensol® AO 89, ethers of the Lutensol® ON brands, in particular Lutensol® ON 30, Lutensol® ON 50, Lutensol® ON 60, Lutensol® ON 65, Lutensol® ON 66, Lutensol® ON 70, Lutensol® ON 79 and Lutensol® ON 80, ethers of the Lutensol® XL brands, in particular Lutensol® XL 300, Lutensol® XL 400, Lutensol® XL 500, Lutensol® XL 600, Lutensol® XL 700, Lutensol® XL 800 , Lutensol® XL 900 and Lutensol® XL 1000, ethers of the Lutensol® AP brands, in particular Lutensol® AP 6, Lutensol® AP 7, Lutensol® AP 8, Lutensol® AP 9, Lutensol® AP 10, Lutensol® AP 14 and Lutensol® AP 20, ethers of the IMBENTIN® brands, in particular the IMBENTIN® AG brands, the IMBENTIN® U brands, the IMBENTIN® C brands, the IMBENTIN® T brands, the IMBENTIN® OA Brands, the IMBENTIN®-POA brands, the IMBENTIN®-N brands and the IMBENTIN®-O brands, as well as ethers of the Marlipal® brands, in particular Marlipal® 1/7, Marlipal® 1012/6, Marlipal® 1618 / 1, Marlipal® 24/20, Marlipal® 24/30, Marlipal® 24/40, Marlipal® O13 / 20, Marlipal® O13 / 30, Marlipal® O13 / 40, Marlipal® O25 / 30, Marlipal® O25 / 70, Marlipal® O45 / 30, Marlipal® O45 / 40, Marlipal® O45 / 50, Marlipal® O45 / 70 and Marlipal® O45 / 80.

Of these, aminoalkyl (meth) acrylates and aminoalkyl (meth) acrylamides, for example, N- (3-dimethylaminopropyl) methacrylamide (DMAPMAM), and hydroxyalkyl (meth) acrylates, for example, 2-hydroxyethyl methacrylate (HEMA) are particularly preferred.

Very particularly preferred mixtures for the preparation of the polymeric structure improvers comprise methyl methacrylate, butyl methacrylate, lauryl methacrylate, stearyl methacrylate and / or styrene.

These components can be used individually or as mixtures.

The preferred polymeric structural improvers generally have a molecular weight in the range of 10,000 to 1,000,000 g / mol, preferably in the range of 15 * 10 ³ to 500 * 10 ³ g / mol, and more preferably in the range of 20 * 10 ³ to 300 * 10 ³ g / mol, without this being a limitation. These values are based on the weight average molecular weight of the polydisperse polymers in the composition. This size can be determined by gel permeation chromatography in a known manner.

The preparation of the polymeric structural improvers from the compositions described above is known per se. Thus, these polymers can be carried out in particular by radical polymerization, as well as related processes, such as ATRP (= atom transfer radical polymerization) or RAFT (= reversible addition fragmentation chain transfer).

The usual free-radical polymerization is set forth, inter alia, in Ullmanns Encyclopedia of Industrial Chemistry, Sixth Edition. In general, a polymerization initiator is used for this purpose.

These include, among others, the azo initiators well known in the art, such as AIBN and 1,1-azobiscyclohexanecarbonitrile, and peroxy compounds such as methyl ethyl ketone peroxide, acetylacetone peroxide, dilauryl peroxide, tert-butyl per-2-ethylhexanoate, ketone peroxide, tert-butyl peroctoate, methyl isobutyl ketone peroxide, cyclohexanone peroxide, Dibenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, 2,5-bis (2-ethylhexanoylperoxy) -2,5-dimethylhexane, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxy-3,5,5 trimethylhexanoate, dicumyl peroxide, 1,1-bis (tert-butylperoxy) cyclohexane, 1,1-bis (tert-butylperoxy) 3,3,5-trimethylcyclohexane, cumyl hydroperoxide, tert-butyl hydroperoxide, bis (4-tert. Butylcyclohexyl) peroxydicarbonate, mixtures of two or more of the aforementioned compounds with one another and mixtures of the abovementioned compounds with unspecified compounds which can also form radicals.

The ATRP method is known per se. It is believed that this is a "living" radical polymerization without any limitation to the description of the mechanism. In these methods, a transition metal compound is reacted with a compound having a transferable atomic group. Here, the transferable atomic group is transferred to the transition metal compound, whereby the metal is oxidized. This reaction forms a radical that adds to ethylenic groups. However, the transfer of the atomic group to the transition metal compound is reversible so that the atomic group is re-transferred to the growing polymer chain, forming a controlled polymerization system. Accordingly, the structure of the polymer, the molecular weight and the molecular weight distribution can be controlled.

This reaction is, for example, of JS. Wang, et al., J. Am. Chem. Soc., Vol.117, p.5614-5615 (1995 ), from Matyjaszewski, Macromolecules, vol.28, p.7901-7910 (1995) s. In addition, the patent applications disclose WO 96/30421 . WO 97/47661 . WO 97/18247 . WO 98/40415 and WO 99/10387 Variants of the previously discussed ATRP.

Furthermore, the polymers according to the invention can also be obtained, for example, by RAFT methods. This method is for example in WO 98/01478 which is expressly referred to for purposes of the disclosure.

The polymerization can be carried out at atmospheric pressure, lower or higher pressure. The polymerization temperature is not critical. In general, however, it is in the range of -20 ° - 200 ° C, preferably 0 ° - 130 ° C and particularly preferably 60 ° - 120 ° C.

The polymerization can be carried out with or without solvent. The term of the solvent is to be understood here broadly.

Preferably, the polymerization is carried out in a nonpolar solvent. These include hydrocarbon solvents such as aromatic solvents such as toluene, benzene and xylene, saturated hydrocarbons such as cyclohexane, heptane, octane, nonane, decane, dodecane, which may also be branched. These solvents can be used individually or as a mixture. Particularly preferred solvents are mineral oils, natural oils and synthetic oils and mixtures thereof. Of these, mineral oils are most preferred.

In a preferred embodiment, the polymeric structural improvers may be random copolymers.

The polymeric structural improver is present in the grease in an amount in the range of 0.1 to 10 wt.%, More preferably 0.5 to 5 wt.%, Based on the total weight.

The lubricating oils contained in the lubricating greases of the invention include, in particular, mineral oils, synthetic oils and natural oils.

Mineral oils are known per se and commercially available. They are generally obtained from petroleum or crude oil by distillation and / or refining and, if appropriate, further purification and refining processes, the term "mineral oil" in particular falling to the relatively high-boiling fractions of crude oil or crude oil. In general, the boiling point of mineral oil is higher than 200 ° C, preferably higher than 300 ° C, at 5000 Pa. The production by smoldering of shale oil, coking of hard coal, distillation under exclusion of lignite and hydration of coal or lignite is also possible. To a small extent, mineral oils are also produced from raw materials of plant origin (eg from jojoba, rapeseed) or animal (eg claw oil) of origin. Accordingly, mineral oils, depending on the origin of different proportions of aromatic, cyclic, branched and linear hydrocarbons.

In general, a distinction is made between paraffin-based, naphthenic and aromatic fractions in crude oils or mineral oils, the terms paraffin-based fraction being longer-chain or highly branched isoalkanes and naphthenic fraction being cycloalkanes. In addition, mineral oils, depending on their origin and refinement, have different proportions of n-alkanes, isoalkanes with a low degree of branching, so-called monomethyl-branched paraffins, and compounds with heteroatoms, in particular O, N and / or S, which are attributed to polar properties , However, the assignment is difficult because individual alkane molecules have both long-chain branched groups and cycloalkane groups and may have aromatic moieties. For the purposes of the present invention, the assignment can be made, for example, according to DIN 51 378. Polar proportions may also be determined according to ASTM D 2007.

The proportion of n-alkanes in preferred mineral oils is less than 3 wt .-%, the proportion of O, N and / or S-containing compounds less than 6 wt .-%. The proportion of aromatics and monomethyl branched paraffins is generally in the range of 0 to 40 wt .-%. According to an interesting aspect, mineral oil mainly comprises naphthenic and paraffinic alkanes, which generally have more than 13, preferably more than 18 and most preferably more than 20 carbon atoms. The proportion of these compounds is generally ≥ 60 wt .-%, preferably ≥ 80 wt .-%, without this being a restriction. A preferred mineral oil contains from 0.5 to 30% by weight of aromatic fractions, from 15 to 40% by weight of naphthenic fractions, from 35 to 80% by weight of paraffinic fractions, up to 3% by weight of n-alkanes and 0.05% to 5 wt .-% polar compounds, each based on the total weight of the mineral oil.

• n-Alkane mit ca. 18 bis 31 C-Atome: $$\mathrm{0,7}-\mathrm{1,0}\mathrm{}\%,$$
  
• gering verzweigte Alkane mit 18 bis 31 C-Atome: $$\mathrm{1,0}-\mathrm{8,0}\mathrm{}\%,$$
  
• Aromaten mit 14 bis 32 C-Atomen: $$\mathrm{0,4}-\mathrm{10,7}\mathrm{}\%,$$
  
• Iso- und Cyclo-Alkane mit 20 bis 32 C-Atomen: $$\mathrm{60,7}-\mathrm{82,4}\mathrm{}\%,$$
  
• polare Verbindungen: $$\mathrm{0,1}-\mathrm{0,8}\mathrm{}\%,$$
  
• Verlust: $$\mathrm{6,7}-\mathrm{19,4}\mathrm{}\%.$$
  

An analysis of particularly preferred mineral oils, which was carried out by means of conventional methods, such as urea separation and liquid chromatography on silica gel, shows, for example, the following constituents, the percentages being based on the total weight of the particular mineral oil used:

• n-alkanes with about 18 to 31 C atoms: $$0.7-1.0\mathrm{}\%.$$
  
• low branched alkanes with 18 to 31 C atoms: $$1.0-8.0\mathrm{}\%.$$
  
• Aromatics with 14 to 32 C atoms: $$0.4-10.7\mathrm{}\%.$$
  
• Iso- and cycloalkanes with 20 to 32 carbon atoms: $$60.7-82.4\mathrm{}\%.$$
  
• polar compounds: $$0.1-0.8\mathrm{}\%.$$
  
• Loss: $$6.7-19.4\mathrm{}\%,$$
  

Valuable information regarding the analysis of mineral oils and an enumeration of mineral oils which have a different composition can be found, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 5 ^th Edition on CD-ROM, 1997, keyword "lubricants and related products".

Synthetic oils include, but are not limited to, organic esters such as diesters and polyesters, polyalkylene glycols, polyethers, synthetic hydrocarbons, especially polyolefins, of which polyalphaolefins (PAO) are preferred, silicone oils and perfluoroalkyl ethers. They are usually slightly more expensive than the mineral oils, but have advantages in terms of their performance.

Natural oils are animal or vegetable oils, such as claw oils or jojoba oils.

These lubricating oils can also be used as mixtures and are often commercially available.

Preferably, the grease comprises 69.9 to 98.9 wt .-%, in particular 75 to 95 wt .-% lubricating oil, based on the total weight.

The thickening agents contained in the lubricating greases according to the invention are known per se in the art and can be obtained commercially. These are among others in Ullmann's Encyclopedia of Industrial Chemistry, Sixth Edition, Vol. 20, 200, Wiley, ISBN 3-527-30385-5 , in T. Mang and W. Dresel, Lubricants and Lubrication, 2001, Wiley, ISBN 3-527-29536-4 , and Wilfried J. Bartz et al, greases, expert Verl., 2000, ISBN 3-8169-1533-7 , These include in particular soap thickeners, inorganic thickeners and polymeric thickeners.

The soap thickeners generally comprise at least one metal component and at least one carboxylic acid anion component.

The usual metal components include in particular the alkali metals such as lithium, sodium and potassium, the alkaline earth metals such as calcium or barium and aluminum.

The carboxylic acid anion component generally comprises anions derived from long chain carboxylic acids, many of which have from 6 to 30 carbon atoms. These include, in particular, stearic acid, 12-hydroxystearic acid, octadecanoic acid, eicosanoic acid and hexadecanoic acid.

Further, the carboxylic acid anion component may include anions derived from short chain carboxylic acids having 1 to 6 carbon atoms or from aromatic carboxylic acids. These include in particular acetic acid, propanoic acid and butanoic acid and benzoic acid.

The soap thickeners can be used as such in the process to produce a dispersion comprising a fatty structure. Furthermore, these can also be prepared in situ from the corresponding acids or their derivatives, for example their esters, as well as basic metal compounds.

The preferred acids have been previously set forth. With regard to the esters, it should be noted that esters having a short-chain alcohol radical with 1 to 6 Carbon atoms, for example the methyl, ethyl, propyl and / or butyl esters are preferred.

The preferred basic compounds include, in particular, the oxides, hydroxides and carbonates of the abovementioned metals.

Preferred soap thickeners include lithium 12-hydroxystearate, lithium complex soaps, aluminum complex soaps, and calcium complex soaps.

Furthermore, the basic compounds for the preparation of the soaps can be added in an excess or deficiency, resulting in under- or overbased compounds.

In addition, inorganic thickening agents can be used. These include in particular organophilic clays, which may be derived from bentonite, and silica gel.

In addition, polymeric thickeners can be used. These include polyureas as well as thermoplastic powders such as polytetrafluoroethylene and fluoroethylene propylene.

The lubricating grease preferably comprises 0.01 to 30% by weight, more preferably 0.2 to 15% by weight and most preferably 0.5 to 10% by weight of thickener, based on the total weight.

The weight ratio of lubricating oil to thickener in the grease is generally in the range of 100: 1 to 100: 30, preferably 100: 2 to 100: 25, especially 100: 5 to 100: 15.

Furthermore, the grease according to the invention may contain further additives and additives.

These additives include, but are not limited to, viscosity index improvers, antioxidants, antiaging agents, anti-wear agents, corrosion inhibitors, detergents, dispersants, EP additives, friction modifiers, dyes, fragrances, metal deactivators, and / or demulsifiers.

Preferably, a lubricating grease according to the invention has a water resistance of 1 to 50%, particularly preferably in the range of 5 to 35%. The cone penetration of preferred greases is in the range of 175 to 385 dmm, more preferably in the range of 220 dmm to 340 dmm.

The water resistance can be determined according to ASTM D 4049. The cone penetration can be measured according to ASTM D 1403.

According to a particular aspect of the present invention, special greases can be used at very low temperatures. Preferably, the greases can be used below a temperature of 0 ° C, more preferably of -10 ° C. Furthermore, preferred lubricating greases can also be used at high temperatures of at least 50.degree. C., particularly preferably at least 90.degree.

The production of greases according to the invention can be carried out according to the usual methods, which can be taken from the aforementioned prior art.

In general, in a structure-forming phase, the grease structure or grease matrix is generated by physico-chemical processes. Various processes take place, such as the aggregation of thickener crystallites, the formation of soap micelles by incorporation and adsorption of base oil molecules, the melting of the soap micelles (= heating above the melting point of the soap molecules) and finally the recrystallization of the soap molecules (= targeted cooling).

In many cases, a metal soap is produced from precursors in a first stage. In the reaction phase, metal soap molecules are generated by reaction of the corresponding starting materials in the base oil. The metal soap molecules are present as fine crystals. This level is optional as it is not necessary by choosing appropriate precursors.

The addition of the polymeric structure improvers can be done before, during or after the patterning phase. For example, the polymeric structure improver may first be prepared in a mineral oil. Subsequently, a thickener, or precursors for the preparation of the thickener, are added to the resulting mixture.

Furthermore, the polymeric structural improver may be added after the patterning phase, for example, to a grease. Preferably, the polymeric structural enhancer is added in a liquid at 25 ° C composition of a dispersion having a fatty structure.

The term "fat structure" is known in the art, and this structure may be termed spongy. This structure of the dispersion can be detected for example by microscopic images, wherein the lubricating oil is kept in a thickener.

The composition can be both a dispersion and a solution. Accordingly, these compositions have at least one liquid medium.

Particularly preferred media include, in particular lubricating oils, which can also be used for the preparation of the dispersion, which comprises at least one thickener and at least one lubricating oil.

Liquid media for dispersing or dissolving the polymeric structural improvers described above are known per se, which media should be compatible with the dispersion comprising at least one thickener and at least one lubricating oil. Compatibility here means the miscibility of the medium with the dispersion, which comprises at least one thickener and at least one lubricating oil.

According to a particular aspect of the present invention, the composition having at least one polymeric structural improver liquid at 25 ° C has a viscosity at 25 ° C in the range of 0.01 mm ² / s to 100000 mm ² / s, preferably 0.1 mm ² / s up to 20000 mm ² / s and more preferably from 1 mm ² / s to 10000 mm ² / s according to DIN 51562 on.

The concentration of the polymeric structure improver in the liquid composition at 25 ° C is preferably in the range of 1 to 99% by weight, more preferably in the range of 5 to 89% by weight, and most preferably in the range of 10 to 80% by weight. %, based on the total weight of the composition.

The ratio of the weight of the dispersion to the weight of the 25 ° C liquid composition comprising at least one polymeric structure improver is preferably in the range of 100: 1 to 1: 1, more preferably in the range of 50: 1 to 5: 1 and most preferably in the range of 25: 1 to 10: 1.

The composition which is liquid at 25 ° C. can be added inter alia during a mechanical phase following the structure-forming phase.

Furthermore, the liquid composition at 25 ° C can be added to a finished grease after the mechanical phase. By this particular aspect of the present invention, for example, a large amount of a simple grease can be prepared, which can then be adapted in a further step to the particular needs of the end customer by the addition of the liquid at 25 ° C composition, which may contain other additives , As a result, a particularly economical production of small amounts of special greases is possible.

According to a particular embodiment of the present invention, the water resistance can be improved by at least 30%, more preferably by at least 50% and most preferably by at least 70%, based on the water resistance of the dispersion to which the liquid composition at 25 ° C is added become.

According to a particular aspect of the present invention, the dispersion comprising the fatty structure and the composition which is liquid at 25 ° C. are substantially biodegradable. Preferably, this is measured according to RAL-ZU 64.

The addition of the composition comprising the fat structure at 25 ° C. can be carried out by generally known methods. These include, but are not limited to, stirring, mixing, kneading, rolling and / or homogenizing.

The temperature at which the dispersion comprising the fat structure at 25 ° C. is added is not critical per se. At a high temperature, the liquid composition at 25 ° C is often easier to incorporate in the dispersion. However, the fat structure must be stable at the addition temperature.

Preferably, the composition which is liquid at 25 ° C is added at a temperature to the dispersion comprising the fatty structure which is below the dropping point of the dispersion prior to the addition of the liquid composition. The dropping point can be determined according to ASTM D 2265.

The composition which is liquid at 25 ° C. is particularly preferably added at a temperature to the dispersion comprising fatty structure, which is at least 40 ° C., very particularly preferably at least 60 ° C., below the dropping point of the dispersion before the addition of the liquid composition.

According to one preferred variant of the process according to the invention, the composition which is liquid at 25 ° C. can be added at a temperature in the range from 0 ° C. to 75 ° C., in particular in the range from 25 ° C. to 70 ° C.

In the following, the invention will be explained in more detail by means of examples and comparative examples, without the invention being restricted to these examples.

The following abbreviations are used below.
KV 100, KV 40 = kinematic viscosity, measured according to DIN 51562 at 100 ° C and 40 ° C

Typically, the polymer solutions described in the example are measured in a 150 N measuring oil, the data in () shows the polymer concentration used.
[η] denotes the intrinsic viscosity, measured according to DIN ISO 16281, Part 6.

Production Example 1 Preparation of PAMA / methacrylic acid polymers

In a 2 liter four-necked flask equipped with stirrer, thermometer and reflux condenser, 6.1 g of methacrylic acid and 603.9 g of a C10-C18 alkyl methacrylate are dissolved in 499 g of 100 N oil, eg 100 SN from Kuwait Petroleum. The solution is rendered inert by adding 10 g of dry ice and then the temperature is increased to 82 ° C. After reaching the temperature, the polymerization is started by adding 0.73 g of initiator (tert-butylper-2-ethylhexyl-hexanoate). After 4 hours of reaction time, 1.21 g of initiator and after a further 4 hours 111 g of 100 N oil is added. The resulting polymer solution is about 50%.
KV 100 (2% in 150 N oil): 10.11 mm ² / s
KV 40 (2% in 150 N oil): 58.43 mm ² / s
[η] 136 cm ³ / g

Production Example 2 Preparation of a PAMA polymer without acid function

Preparation analogous to Example 1
Batch polymerisation, 82 ° C, 55% in 100 N oil
495.0 g of 100 N oil
605.0 g of C12-C18 alkyl methacrylate
0.73 g initiator (0.12%)
Postfeed step (after 4 h): 1.21 g initiator (0.20%)
Dilute to 50% with 110.0 g of 100 N oil
KV 100 (2% in 150 N oil): 9,98 mm ² / s
KV 40 (2% in 150 N oil): 55.58 mm ² / s
[η] 127 cm ³ / g

Production Example 3 Production of a NLGI Grade 2 Li soap soap (EG 2768)

In a 6 l grease autoclave kettle, equipped with an oil-jacket heater and a mechanical planetary mixer 272 g hydrogenated castor oil (HCO, 181.6 mg KOH / g), 40 g of lithium hydroxide, 32 g Vanlube NA (a diphenylamine from Vanderbilt, Shell, 32 g of Lubad 199 (a calcium salicylate from Shell), and 1440 g of Shell oil HVI 650 and 1330 g of Shell oil HVI 160. The kettle is closed and left for one hour at 100 ° C / 100 U / The resulting reaction water is then drained off and the mixture is heated to 210 ° C. After reaching the peak temperature, the mixture is cooled to 165 ° C. at 200 rpm at a rate of 1 ° C./min 100 rpm further cooled to a temperature of 50 ° C. The kettle is opened and the resulting fat is homogenized at least twice by a three-roll mill and filled into a bucket.

Physical data:

Cone penetration (IP 50) unworked: 285 dmm, after 60 movements 288 dmm (NLGI grade 2), after 100060 movements: 317 dmm.
Drop point (ASTM D566): 197.7 ° C
Water Wash Out (ASTM D 1264): 7.5%
Water Spray Off (ASTM D 4049): 33.8%

example 1

In a mixer (Kenwood Chef) were 990 g of the obtainable according to Preparation Example 3 grease EG 2768, the classification NLGI grade 2 based on Li soaps with 10 g of a solution containing 50 wt .-% of polymers with acid groups, according to the preparation 1 and comprising a lubricating oil, mixed at 60 ° C. The resulting mixture was then homogenized on a three-roll mill (Exact 50 Fa. Exact Apparatebau). The properties of the modified grease were determined below.

In particular, the drop point according to ASTM D 566, the cone penetration according to ASTM D 217 and the water resistance according to ASTM D 4049 were measured. The data obtained are shown in Table 1.

Comparative Example 1

Example 1 was essentially repeated, but no solution was incorporated. The data obtained are shown in Table 1.

Comparative Example 2

Example 1 was substantially repeated except that a solution comprising 50% by weight of polymers without acid groups obtained according to Preparation Example 2 and comprising a lubricating oil was incorporated. The data obtained are shown in Table 1. Table 1 Cone penetration after 60 movements Dropping point water resistance Improvement related to the source fat Ex. 1 291 197 ° C 20% 41% Comp. 1 288 198 ° C 34% - Comp. 2 279 198 ° C 27% 21%

Example 2

In a mixer (Kenwood Chef) were 990 g of F & S Mannheim available grease Farmlub, the classification NLGI grade 2 based on Li soaps with 10 g of a solution containing 50 wt .-% of polymers with acid groups, according to Preparation Example 1 were obtained, and a lubricating oil mixed at 60 ° C. The resulting mixture was then homogenized on a three-roll mill (Exact 50 Fa. Exact Apparatebau). The properties of the modified grease were determined below.

In particular, the drop point according to ASTM D 566, the cone penetration according to ASTM D 217 and the water resistance according to ASTM D 4049 were measured. The data obtained are shown in Table 2.

Comparative Example 3

Example 2 was essentially repeated, but no solution was incorporated. The data obtained are shown in Table 2.

Example 3

Example 2 was substantially repeated, incorporating 40 g of the dispersion comprising 50% by weight of polymers with acid groups obtained according to Preparation Example 1 and a lubricating oil into 960 g of Grease from F & S Mannheim. The data obtained are shown in Table 2.

Comparative Example 4

Example 2 was substantially repeated except that 10 g of a solution comprising 50% by weight of polymers without acid groups obtained in Preparation Example 2 and a lubricating oil was incorporated. The data obtained are shown in Table 2.

Comparative Example 5

Example 3 was substantially repeated except that 20 g of a solution comprising 50% by weight of polymers without acid groups obtained according to Preparation Example 2 and a lubricating oil were incorporated in 980 g of F & S grease. The data obtained are shown in Table 2. Table 2 Cone penetration after 60 movements Dropping point water resistance Improvement related to the source fat Ex. 2 291 182 ° C 20% 68% Comp. 3 251 186 ° C 62% - Ex. 3 294 185 ° C 11% 82% Comp. 4 - 188 ° C 40% 35% Comp. 5 - 183 ° C 28% 55%

Claims (13)

1. Lubricating grease comprising at least one thickener and at least one lubricant oil, characterized in that the lubricating grease comprises at least one polymeric structure improver which can be obtained by polymerizing monomer compositions which consist of

   a) from 0 to 40% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of at least one (meth)acrylate of the formula (I)

   

   where R is hydrogen or methyl, R¹ is a linear or branched alkyl radical having from 1 to 5 carbon atoms,

   b) from 40 to 99.99% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of at least one (meth)acrylate of the formula (II)

   

   where R is hydrogen or methyl, R² is a linear or branched alkyl radical having from 6 to 30 carbon atoms,

   c) from 0.01 to 5% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of monomers comprising acid groups, wherein at least some of the monomers as per component c) comprise at least one carboxyl group,

   d) from 0 to 59.99% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of comonomer; and the lubricating grease comprises from 0.1 to 10% by weight of polymeric structure improvers.
2. Lubricating grease according to Claim 1, characterized in that component c) comprises at least one monomer which is selected from the group consisting of methacrylic acid and/or acrylic acid.
3. Lubricating grease according to one of the preceding claims, characterized in that the polymeric structure improver has a weight-average molecular weight in the range from 15 000 g/mol to 1 000 000 g/mol.
4. Lubricating grease according to one of the preceding claims, characterized in that the thickener is a soap thickener, an inorganic thickener and/or a polymeric organic thickener.
5. Lubricating grease according to one of the preceding claims, characterized in that the lubricating grease comprises additives.
6. Lubricating grease according to one of the preceding claims, characterized in that the lubricating grease has a water resistance of from 1 to 50%, measured in accordance with ASTM D 4049.
7. Lubricating grease according to one of the preceding claims, characterized in that the lubricating grease has a cone penetration in the range from 175 dmm to 385 dmm, measured in accordance with ASTM D 1403.
8. Lubricating grease according to one of the preceding claims, characterized in that the lubricating grease comprises from 1 to 30% by weight of thickener.
9. Lubricating grease according to one of the preceding claims, characterized in that the lubricating grease comprises from 69.9 to 98.9% by weight of lubricant oil.
10. Process for producing lubricating grease by preparing a mixture which comprises at least one thickener, at least one lubricant oil and a polymeric structure improver which can be obtained by polymerizing monomer compositions which consist of

    a) from 0 to 40% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of one or more ethylenically unsaturated ester compounds of the formula (I)

    

    where R is hydrogen or methyl, R¹ is a linear or branched alkyl radical having from 1 to 5 carbon atoms,

    b) from 40 to 99.99% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of one or more ethylenically unsaturated ester compounds of the formula (II)

    

    where R is hydrogen or methyl, R² is a linear or branched alkyl radical having from 6 to 30 carbon atoms,

    c) from 0.01 to 5% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of monomers comprising acid groups, wherein at least some of the monomers as per component c) comprise at least one carboxyl group,

    d) from 0 to 59.99% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improvers, of comonomer; and the lubricating grease comprises from 0.1 to 10% by weight of polymeric structure improvers.
11. Process according to Claim 10, characterized in that the polymeric structure improver is added to a dispersion which has grease structure and comprises at least one thickener and at least one lubricant oil.
12. Process according to Claim 10 or 11, characterized in that the polymeric structure improver is added in a composition, liquid at 25°C, of the dispersion.
13. Use of a polymer which can be obtained by polymerizing monomer compositions which consist of

    a) from 0 to 40% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improver, of one or more ethylenically unsaturated ester compounds of the formula (I)

    

    where R is hydrogen or methyl, R¹ is a linear or branched alkyl radical having from 1 to 5 carbon atoms,

    b) from 40 to 99.99% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improver, of one or more ethylenically unsaturated ester compounds of the formula (II)

    

    where R is hydrogen or methyl, R² is a linear or branched alkyl radical having from 6 to 30 carbon atoms,

    c) from 0.01 to 5% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improver, of monomers comprising acid groups, wherein at least some of the monomers as per component c) comprise at least one carboxyl group,

    d) from 0 to 59.99% by weight, based on the weight of the monomer compositions for preparing the polymeric structure improver, of comonomer

    as a structure improver in lubricating greases; and wherein the lubricating grease comprises from 0.1 to 10% by weight of polymeric structure improvers.