EP2714871A1

EP2714871A1 - Lubricant composition with phosphorus-functionalized polymers

Info

Publication number: EP2714871A1
Application number: EP12716392.1A
Authority: EP
Inventors: Boris Eisenberg; Ellen Suchert
Original assignee: Evonik Oil Additives GmbH
Current assignee: Evonik Oil Additives GmbH
Priority date: 2011-05-24
Filing date: 2012-04-19
Publication date: 2014-04-09
Anticipated expiration: 2032-04-19
Also published as: US9914896B2; EP2714871B1; BR112013029905A2; SG194799A1; CA2837001A1; JP2014518925A; CA2837001C; CN103443257A; US20140135242A1; KR20140032388A; WO2012159828A1; DE102011076364A1

Abstract

The present invention relates to a lubricant composition comprising at least one polyalkyl (meth)acrylate, comprising repeating units derived from (meth)acrylates having 6 to 22 carbon atoms in the alcohol residue, the polyalkyl (meth)acrylate comprising repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom. The present invention further describes a polyalkyl (meth)acrylate which is suitable for a lubricant composition of this kind, and also describes the use of a polyalkyl (meth)acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom, for the purpose of reducing friction.

Description

LUBRICANT COMPOSITION WITH PHOSPHOROUS-FUNCTIONALIZED POLYMERS

The present invention relates to a lubricant composition with phosphate-functionalized polymers, phosphate-functionalized polyalkyl (meth) acrylates, and the use of a polyalkyl (meth) acrylate to reduce friction.

Known is the wear-reducing effect of low molecular weight

(Thio) phosphate esters in lubricants. So they are used as standard in wear protection packages. These additives are going through

Increased temperature or by plastic deformation (pressure) activated and form a separating and lubricious layer on the metal surface.

US Pat. No. 3,484,504 describes reaction products of a basic, nitrogen-containing polymer and a (thio) phosphoric acid partial ester and their use as lubricating oil additive. Examples of the nitrogen-containing monomer are e.g. N, N-dimethylaminoethyl (meth) acrylate or morpholinoethyl (meth) acrylate.

Other comonomers may u.a. C2-C18 acrylates or methacrylates,

Styrene monomers, vinyl esters, allyl esters and vinyl ethers.

The documents DE 69431710 A and EP 0 686 690 A describe lubricant compositions for transmissions with improved

Schlammdispergiereigenschaften. The improved slurry dispersion is achieved by the interaction of a phosphorus-containing compound (e.g., phosphate ester, phosphonate ester) and a nitrogen-containing oil solvent

Copolymer. The nitrogen-containing monomer here is, for example, N, N-dialkylaminoalkyl (meth) acrylate. Suitable comonomers are C ₄ acrylates or C2

Methacrylates listed.

The publications WO 2003/089554 and US 6,586,375 describe

Lubricating compositions containing a salt of a nitrogen-containing poly (meth) acrylate and a phosphoric acid partial ester. Here are the improved effects on dispersibility, Vl-effect and wear-reducing properties in lubricating oil compositions claimed for engines and transmissions. Nitrogen-containing monomers used here were N-vinylpyrrolidone and Ν, Ν-dimethylaminopropylmethacrylamide.

Comonomers are here u.a. C1 -C30 acrylates or methacrylates. The document US 2006/0135380 describes a method for lubricating a gearbox with the aim of getting transmission fatigue under control. Used here are the compositions of WO 2003/089554 and the

US 6,586,375.

It is thus known from the prior art that the use of salts of phosphoric acid partial esters and a nitrogen-containing polymer to improved effects in the sludge dispersion (DE 69431710, EP 0686690) and the anti-wear properties, the dispersion behavior and the viscosity-temperature behavior of engines and gear oils ( WO 2003/089554,

US 6,586,375) leads. The lubricant compositions set out above already lead to a usable property profile. However, there is a continuing need to improve this property profile.

In view of the prior art, it is now the object of the present

Invention to provide lubricant compositions that go beyond the prior art.

In particular, the lubricant compositions should have a high

Have wear protection, at the same time an excellent

Friction behavior should be provided.

In addition, it is an object of the present invention to provide wear-inhibiting polymers for a lubricant composition

provide, which can be used in larger quantities in industrial hydraulic oils, without this to a great extent adverse effects occur. Further, the lubricant compositions are said to have increased hydrolytic stability to provide an extended temperature range under stable conditions for the use of lubricant compositions.

Another object of the invention was to

To provide lubricant compositions and friction-reducing polymers as additives that can be produced easily and inexpensively, in particular, commercially available components should be used.

Here, the production should be possible on an industrial scale without the need for new or structurally complex systems. Furthermore, the additive should lead to an improvement in fuel consumption, without affecting the environmental compatibility of the lubricant composition.

These and other objects which are not explicitly mentioned, but which can be readily deduced or deduced from the contexts discussed hereinbelow, are solved by a lubricant composition having all the features of patent claim 1. Advantageous modifications of the lubricant composition according to the invention are provided in the subclaims 2 to 1 1 under protection.

The subject of the present invention is accordingly a

A lubricant composition containing at least one polyalkyl (meth) acrylate comprising repeat units derived from (meth) acrylates having 6 to 22

Carbon atoms are derived in the alcohol radical, which is characterized in that the polyalkyl (meth) acrylate comprises repeating units of

ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom are derived.

This succeeds in an unpredictable way one

To provide lubricant composition with an improved property profile. Among others, the following advantages can be achieved by the lubricant composition according to the invention:

In particular, the present invention can be used

Lubricating compositions surprisingly improved wear protection, with a simultaneously excellent friction behavior. In particular embodiments of the present invention, the

Friction behavior can be increased together with the wear protection. This is particularly surprising since usually the addition of an additive to the

Wear reduction leads to a simultaneous deterioration of the coefficient of friction.

Surprisingly, it is possible by the invention

Lubricating compositions to achieve increased hydrolysis and temperature stability compared to the lubricant compositions of the prior art comprising salts of phosphoric acid partial esters and a nitrogen-containing polymer.

Another advantage here is that the wear-reducing properties and the viscosity index-improving effect of the invention used

Polyalkyl (meth) acrylate (PAMAs) comprising repeating units having at least one covalently bonded phosphorus atom in one component.

By virtue of this covalent bond, improved hydrolytic stability of the lubricant composition, in particular at thermal hot spots, is achieved, which leads to improved wear protection over time.

Furthermore, polymers with a wear-reducing effect for a

Provided lubricant composition, which show no dispersibility, but rather are demulsible (water-separating), so that they can be used in larger quantities in industrial hydraulic oils.

Moreover, the present invention provides lubricant compositions that can be produced easily and inexpensively, in particular commercially available components can be used. Here, the production can be done on an industrial scale, without the need for new or structurally complex systems are needed.

Furthermore, the lubricant composition can lead to an improvement in fuel consumption, with no adverse effects on the environmental compatibility are connected.

The present invention describes a lubricant composition.

Lubricating compositions, in particular lubricating oils serve for

Reduction of friction and wear, as well as for power transmission, cooling, vibration damping, sealing effect and corrosion protection. In this case, it is customary to distinguish transmission oils from other lubricating oils which can be used, for example, to lubricate engines. These differences usually show up, in particular, in the added additives, with gear oils having much higher levels of wear protection and extreme pressure additives in comparison to engine oils. According to a particular aspect of the present invention, the lubricant composition can be used as hydraulic oil.

The lubricant composition of the present invention contains at least one polyalkyl (meth) acrylate comprising repeating units derived from (meth) acrylates having 6 to 22 carbon atoms in the alcohol residue, wherein the

Polyalkyl (meth) acrylate comprises repeating units of ethylenically unsaturated monomers having at least one covalently bonded

Are derived phosphorus atom.

Polyalkyl (meth) acrylates are polymers, by the polymerization of

Alkyl (meth) acrylates can be obtained. The term (meth) acrylates include methacrylates and acrylates as well as mixtures of both. These monomers are well known.

Polyalkyl (meth) acrylates preferably comprise at least 40%, more preferably at least 60%, more preferably at least 80%, and most preferably at least 90%, of repeating units derived from alkyl (meth) acrylates are. According to a particular aspect of the present invention are

Polyalkyl (meth) acrylates preferably comprising at least 20 wt .-%, more preferably at least 40 wt .-%, particularly preferably at least 60 wt .-% and most preferably at least 80 wt .-% repeating units of alkyl (meth ) acrylates having 6 to 22 carbon atoms in

Alcohol are derived.

Of particular interest are, inter alia, polyalkyl (meth) acrylates comprising repeating units derived from (meth) acrylates having 6 to 22 carbon atoms in the alcohol radical, and repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded one

Phosphorus atom are derived, preferably a weight average

Molecular weight M _w in the range of 5000 to 10,000,000 g / mol, preferably 10,000 to 600,000 g / mol and most preferably 15,000 to 80,000.

The number-average molecular weight M _n may preferably be in the range of 1,000 to 500,000 g / mol, more preferably 7,500 to 500,000 g / mol, and all

particularly preferably from 10,000 to 80,000 g / mol.

In addition, polyalkyl (meth) acrylates, whose

Polydispersity index M _w / M _n in the range of 1.1 to 5.0, more preferably in the range of 1.4 to 4.5, and most preferably in the range of 1.6 to 3.0.

The number average and weight average molecular weights can be determined by known methods, for example, gel permeation chromatography (GPC), preferably using a PMMA standard.

Preferably, the molecular weight of the polymer may be carried out prior to derivatization thereof with a phosphorus compound.

Preferred polyalkyl (meth) acrylates comprise a) from 0 to 40% by weight, in particular from 1 to 25% by weight and more preferably from 2 to 15% by weight, of recurring units derived from (meth) acrylates of the formula (I) wherein R is hydrogen or methyl and R ^{1 is} an alkyl radical having 1 to 5 carbon atoms,

20 to 99.9% by weight, preferably 50 to 99.9% by weight, in particular at least 70% by weight and particularly preferably at least 80% by weight of repeat units derived from (meth) acrylates of the formula (II)

where R is hydrogen or methyl and R ^{2 is} an alkyl radical having 6 to 22 carbon atoms,

0 to 20% by weight, preferably 0.1 to 20% by weight, preferably 0.5 to 15% by weight and particularly preferably 1 to 10% by weight of repeat units derived from (meth) acrylates of the formula (III) are derived

wherein R represents hydrogen or methyl and R ^{3 represents} an alkyl radical having 23 to 4000 carbon atoms, and

0.1 to 22% by weight, preferably 1 to 18% by weight, preferably 2 to 15% by weight and more preferably 4 to 12% by weight of repeat units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom are derived.

The polyalkyl (meth) acrylates can preferably be obtained by free-radical polymerization. Accordingly, the proportion by weight of the respective repeating units which comprise these polymers results from the proportions by weight of corresponding monomers used to prepare the polymers.

Examples of (meth) acrylates of the formula (I) include linear and branched (meth) acrylates which are 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; and

Cycloalkyl (meth) acrylates, such as cyclopentyl (meth) acrylate.

The (meth) acrylates of the formula (II) include, in particular, linear and branched (meth) acrylates. which are 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, 2-methylpentadecyl (meth) acrylate, 2-ethyltetradecyl (meth) acrylate, 2-propyl tridecyl (meth) acrylate, 2-butyl dodecyl (meth) acrylate, 2-methylhexadecyl (meth) acrylate, 2-pentyldodecyl (meth) acrylate,

2-hexyldecyl (meth) acrylate, 2-hexylundecyl (meth) acrylate, n-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,

Docosyl (meth) acrylate;

(Meth) acrylates derived from unsaturated alcohols, such as. B.

Oleyl (meth) acrylate; and Cycloalkyl (meth) acrylates, such as cyclohexyl (meth) acrylate, 3-vinylcyclohexyl (meth) acrylate, bornyl (meth) acrylate, 2,4,5-tri-t-butyl-3-vinylcyclohexyl (neth) acrylate, 2, 3,4,5-tetra-t-butylcyclohexyl (Kunneth) acrylate.

Examples of monomers of the formula (III) include linear and branched (meth) acrylates derived from saturated alcohols, such as

Cetyleicosyl (meth) acrylate, Stearyleicosyl (meth) acrylate and / or

Eicosyltetratriacontyl (meth) acrylate; Cycloalkyl (meth) acrylates, such as 2,3,4,5-tetra-t-hexylcyclohexyl (meth) acrylate.

According to a particular embodiment of the present invention, the monomers of the formula (III) include so-called polyolefin-based macromonomers with (meth) acrylate groups which are described, inter alia, in DE 10 2007 032 120 A1, filed on July 9, 2007 with the German Patent Office with the application number DE102007032120.3; and DE 10 2007 046 223 A1 filed on 26.09.2007 with the German Patent Office with the application number DE 102007046223.0; wherein the disclosures of these references, in particular the therein described (meth) acrylates having at least 23 carbon atoms in the radical for purposes of disclosure in the present application are incorporated by reference thereto.

Polyolefin-based macromonomers are known in the art. These

Repeating units comprise at least one group derived from polyolefins. Polyolefins are known in the art, these by

Polymerization of alkenes and / or alkadienes selected from the elements

Carbon and hydrogen, for example, C2-Cio alkenes such as ethylene, propylene, n-butene, isobutene, norbornene and / or C ₄ -Cio alkadienes such as butadiene, isoprene, norbornadiene, can be obtained. The recurring units derived from polyolefin-based macromonomers preferably comprise at least 70% by weight and more preferably at least 80% by weight and most preferably at least 90% by weight of groups derived from alkenes and / or alkadienes Weight of repeating units derived from polyolefin-based macromonomers. In this case, the polyolefinic groups may in particular also be hydrogenated. In addition to the For groups derived from alkenes and / or alkadienes, repeat units derived from polyolefin-based macromonomers may include other groups. These include low levels of copolymerizable

Monomers. These monomers are known per se and include, inter alia, alkyl (meth) acrylates, styrenic monomers, fumarates, maleates, vinyl esters and / or

Vinyl ethers. The proportion of these groups based on copolymerizable monomers is preferably at most 30% by weight, particularly preferably at most 15% by weight, based on the weight of repeating units derived from polyolefin-based macromonomers. In addition, the repeating units derived from polyolefin-based macromonomers may include initial groups and / or end groups which serve to functionalize or derive from the preparation of polyolefin-based macromonomers

Repeat units are conditional. The proportion of these initial groups and / or end groups is preferably at most 30 wt .-%, particularly preferably at most 15 wt .-%, based on the weight of the polyolefin-based

Macromonomers derived repeating units.

Preferably, the number average molecular weight of

Repeating units derived from polyolefin-based macromonomers in the range of 500 to 50,000 g / mol, more preferably 700 to 10,000 g / mol, in particular 1500 to 4900 g / mol and most preferably 2000 to 3000 g / mol.

These values are obtained in the case of preparation of the comb polymers

Copolymerization of Low Molecular and Macromolecular Monomers via the Properties of the Macromolecular Monomers. In the case of polymer-analogous reactions, this property results, for example, from the macroalcohols and / or macroamines used, taking into account the reacted repeating units of the main chain. In the case of graft copolymerizations, the proportion of polyolefins which have not been incorporated into the main chain can be used to deduce the molecular weight distribution of the polyolefin. The repeating units derived from polyolefin-based macromonomers preferably have a low melting temperature, wherein this is measured by DSC. The melting temperature of the recurring units derived from the polyolefin-based macromonomers is preferably less than or equal to -10 ° C., particularly preferably less than or equal to -20 ° C., particularly preferably less than or equal to -40 ° C. Most preferably, none

Melting temperature according to DSC in the repeating units derived from the polyolefin-based macromonomers are measured.

In addition, the monomers of the formula (III) include, in particular, long-chain branched (meth) acrylates which are described, inter alia, in US Pat. No. 6,746,993 filed on August 7, 2002 with the US Patent Office (USPTO) with the application number 10 / 212,784; and US 2004/077509 filed on 01.08.2003 at the US Patent Office (USPTO) with application number 10 / 632,108;

wherein the disclosures of these references, in particular the therein described (meth) acrylates having at least 23 carbon atoms in the radical for purposes of disclosure in the present application are incorporated by reference thereto.

Alkyl (meth) acrylates with a long-chain alcohol radical, in particular the components (II) and (III), can be obtained, for example, by reacting (meth) acrylates and / or the corresponding acids with long-chain fatty alcohols, in which case a mixture of esters, such as For example, (meth) acrylates with different long-chain alcohol radicals formed. These fatty alcohols include Oxo Alcohol® 791 1, Oxo Alcohol® 7900, Oxo Alcohol® 1 100; Alfol® 610, Alfol® 810, Lial® 125 and Nafol® grades (Sasol); C13-C15 alcohol (BASF); Epal® 610 and Epal® 810 (Afton); Linevol® 79, Linevol® 91 1 and Neodol® 25 (Shell); Dehydad®, Hydrenol® and Lorol® types (Cognis); Acropol® 35 and Exxal® 10 (Exxon Chemicals); Kalcol® 2465 (Kao Chemicals).

The polyalkyl (meth) acrylate comprises repeat units derived from ethylenically unsaturated monomers having at least one covalently bonded one

Are derived phosphorus atom.

In a preferred embodiment of the invention, the polyalkyl (meth) acrylate to be used according to the invention may be reacted with repeating units derived from derived ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom, preferably 0.05 to 1, 5 wt .-%, preferably 0.2 to 0.9 wt .-%, particularly preferably 0.3 to 0.8 wt. % of phosphorus atoms, based on the weight of the polyalkyl (meth) acrylate. These

Polyalkyl (meth) acrylate comprising repeating units derived from (meth) acrylates having 6 to 22 carbon atoms in the alcohol radical are novel and thus also subject of this invention.

Ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom, from which the repeating units of the polyalkyl (meth) acrylate are derived, are known per se. These include, among others

2- (Dimethylphosphato) propyl (meth) acrylate,

2- (Ethylenphosphito) propyl (meth) acrylate,

Dimethylphosphinomethyl (meth) acrylate,

Dimethylphosphonoethyl (meth) acrylate,

Diethyl (meth) acryloylphosphonat,

Dipropyl (meth) acryloyl phosphate,

2- (dibutylphosphono) ethyl (meth) acrylate, and

Diethylphosphatoethyl (meth) acrylate.

It can be provided here that the polyalkyl (meth) acrylate of this preferred embodiment of the invention comprises repeating units derived from phosphorus derivatives of a polar ethylenically unsaturated monomer.

The term "polar ethylenically unsaturated monomer" indicates that the monomer can be radically polymerized, and the term "polar" expresses that the monomer is particularly polar even after reaction with a phosphorus derivative in the vicinity of the reaction site include, in particular, resulting hydroxy groups, which are obtained in the reaction of epoxides.

Further, it may be provided that the polar ethylenically unsaturated monomer from which the phosphorus derivative is derived is a (meth) acrylate having an epoxy group. The phosphorus derivatives of a polar ethylenically unsaturated monomer include, among others

2- (Dimethylphosphato) -3-hydroxy-propyl (meth) acrylate,

2- (ethylenephosphito) -3-hydroxypropyl (meth) acrylate,

3- (meth) acryloyloxy-2-hydroxy-propyl diethyl phosphonate,

3- (meth) acryloyloxy-2-hydroxypropyl dipropyl phosphonate,

3- (Dimethylphosphato) -2-hydroxy-propyl (meth) acrylate,

3- (Ethylenphosphito) -2-hydroxy-propyl (meth) acrylate,

2- (meth) acryloyloxy-3-hydroxypropyl diethyl phosphonate,

2- (meth) acryloyloxy-3-hydroxypropyl dipropyl phosphonate,

2- (dibutylphosphono) -3-hydroxy-propyl (meth) acrylate, and

Diethyl phosphatoethyl (meth) acrylate.

Furthermore, for the preparation of the polyalkyl (meth) acrylates to be used according to the invention, the monomer mixture may comprise monomers which can be copolymerized with the monomers described above. These include, inter alia, aryl (meth) acrylates, such as benzyl methacrylate or phenyl methacrylate, wherein the

Aryl radicals may each be unsubstituted or substituted up to four times;

Styrenic monomers, such as styrene, substituted styrenes with a

Alkyl substituents in the side chain, substituted styrenes with a

Alkyl substituents on the ring such as vinyltoluene and p-methylstyrene, halogenated styrenes such as monochlorostyrenes, dichlorostyrenes, tribromostyrenes and

tetrabromostyrenes;

Itaconic acid and itaconic acid derivatives such as itaconic acid monoester, itaconic diester and itaconic anhydride;

Fumaric acid and fumaric acid derivatives such as fumaric acid monoesters, fumaric diesters and fumaric anhydride;

Vinyl and isoprenyl ethers, for example alkyl vinyl ethers, in particular

Methyl vinyl ether, ethyl vinyl ether and dodecyl vinyl ether;

Vinyl esters, for example vinyl acetate; 1-alkenes, especially 1-butene, 1-pentene, 1-hexene, 1-heptane, 1-octene, 1 -none, 1-decene, 1-undencene, 1-dodecene, 1-tridecene, 1-tetradecene and 1-pentadecene.

According to a particular embodiment, in particular dispersing monomers can be used. Dispersing monomers have long been used for functionalizing polymeric additives in lubricating oils and are therefore known to the person skilled in the art (compare RM Mortier, ST Orszulik (eds.): "Chemistry and Technology of Lubricants", Blackie Academic & Professional, London, 2 ^nd ed 1997). Appropriately, in particular heterocyclic vinyl compounds and / or ethylenically unsaturated, polar ester or amide compounds of the formula (IV)

where R is hydrogen or methyl, X is oxygen, sulfur or an amino group of the formula -NH- or -NR ^a -, in which R ^{a is} an alkyl radical having 1 to 10, preferably 1 to 4, carbon atoms, R ^{2 is} a 2 to 50, in particular from 2 to 30, preferably 2 to 20 carbon atoms comprising radical having at least one, preferably at least two heteroatoms, depicting, are used as d isperg ierende monomers.

Examples of dispersing monomers of the formula (IV) include

Aminoalkyl (meth) acrylates, aminoalkyl (meth) acrylamides, hydroxyalkyl (meth) acrylates, heterocyclic (meth) acrylates and / or carbonyl-containing (meth) acrylates. The hydroxyalkyl (meth) acrylates include, inter alia

2-hydroxypropyl (meth) acrylate,

3,4-dihydroxybutyl (meth) acrylate,

2-hydroxyethyl (meth) acrylate,

3-hydroxypropyl (meth) acrylate, 2,5-dimethyl-1,6-hexanediol (neth) acrylate and

1, 10-decanediol (meth) acrylate.

Carbonyl-containing (meth) acrylates include, for example

2-carboxyethyl (meth) acrylate,

Carboxymethyl (meth) acrylate,

N- (methacryloyloxy) formamide,

Acetonyl (meth) acrylate,

Succinic acid mono-2- (meth) acryloyloxyethyl,

N- (meth) acryloylmorpholine,

N- (meth) acryloyl-2-pyrrolidinone,

N- (2- (meth) acryloyloxyethyl) -2-pyrrolidinone,

N- (3- (meth) acryloyloxypropyl) -2-pyrrolidinone,

N- (2- (meth) acryloyloxypentadecyl) -2-pyrrolidinone,

2-acetoacetoxyethyl (meth) acrylate,

N- (3- (meth) acryloyloxyheptadecyl) -2-pyrrolidinone and

N- (2- (meth) acryloyloxyethyl) ethyleneurea.

The heterocyclic (meth) acrylates include, among others

2- (1-imidazolyl) ethyl (meth) acrylate,

Oxazolidinylethyl (meth) acrylate,

2- (4-morpholinyl) ethyl (meth) acrylate

1- (2-methacryloyloxyethyl) -2-pyrrolidone,

N-methacryloylmorpholine,

N-methacryloyl-2-pyrrolidinone,

N- (2-methacryloyloxyethyl) -2-pyrrolidinone,

N- (3-methacryloyloxypropyl) -2-pyrrolidinone.

The aminoalkyl (meth) acrylates include in particular

N, N-dimethylaminoethyl (meth) acrylate,

N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopentyl (Kunneth) acrylate,

N, N-acrylate Dibutylaminohexadecyl (Kunneth).

Furthermore, aminoalkyl (neth) acrylannides can be used as dispersing monomers, such as N, N-dimethylaminopropyl (meth) acrylamide. Among the preferred heterocyclic vinyl compounds include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 3-ethyl-4-vinylpyridine, 2,3-dimethyl-5-vinylpyridine, vinylpyrimidine, vinylpiperidine,

9-vinylcarbazole, 3-vinylcarbazole, 4-vinylcarbazole, 1-vinylimidazole, N-vinylimidazole, 2-methyl-1-vinylimidazole, N-vinylpyrrolidone, N-vinylpyrrolidine, 3-vinylpyrrolidine, N-vinylcaprolactam, N-vinylbutyrolactam, vinyloxolane, Vinylfuran, vinylthiophene, vinylthiolane, vinylthiazoles and hydrogenated vinylthiazoles, vinyloxazoles and hydrogenated vinyloxazoles.

The particularly preferred dispersing monomers include, in particular, ethylenically unsaturated compounds which comprise at least one nitrogen atom, these particularly preferably being selected from the heterocyclic vinyl compounds and / or aminoalkyl (meth) acrylates set out above,

Aminoalkyl (meth) acrylamides and / or heterocyclic (meth) acrylates are selected.

The proportion of comonomers can be varied depending on the purpose and property profile of the polymer. In general, this proportion can be in the range from 0 to 30 wt .-%, preferably 0.01 to 20 wt .-% and particularly preferably 0.1 to 10 wt .-%.

The aforementioned ethylenically unsaturated monomers can be used individually or as mixtures. It is also possible, the

Monomer composition during the polymerization of the main chain to vary to defined structures, such as block copolymers or

Graft polymers. According to a particular aspect of the present invention, the present polyalkyl (meth) acrylates are designed as random copolymers in which the distribution of the two monomers in the chain is random. As a result, surprising advantages can be achieved, which are reflected in particular in better rheology values.

The preparation of the polyalkyl (meth) acrylates from those described above

Zusannnnensetzungen is known per se. Thus, these polymers can in particular by radical polymerization, and related processes, such as ATRP (= atom transfer radical polymerization), RAFT (= reversible addition

Fragmentation Chain Transfer) or NMP (= Nitroxide Mediated

Polymerization) can be obtained.

The ATRP method is known per se. This reaction will be

For example, from J-S. Wang, et al., J. Am. Chem. Soc., Vol. 17, p.5614-5615 (1995), by Matyjaszewski, Macromolecules, vol.28, p.7901-7910 (1995). In addition, patent applications WO 96/30421, WO 97/47661, WO 97/18247, WO 98/40415 and WO 99/10387 disclose variants of the ATRPs discussed above. 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 and WO 2004/083169, which is expressly referred to for purposes of the disclosure.

Furthermore, the polymers according to the invention are obtainable by NMP processes (nitroxide mediated polymerization), which are described, inter alia, in US Pat. No. 4,581,429.

Comprehensively, and in particular with further references, these methods are described inter alia in K. Matyjaszewski, T.P. Davis, Handbook of Radical Polymerization, Wiley Interscience, Hoboken 2002, which is expressly incorporated by reference for purposes of the disclosure.

The free-radical polymerization of the ethylenically unsaturated compounds can be carried out in a manner known per se. The usual free-radical polymerization is set forth, inter alia, in Ullmanns Encyclopedia of Industrial Chemistry, Sixth Edition. In the present invention, the polymerization is started by using at least one polymerization initiator for the radical polymerization. These include, inter alia, the azo initiators well known in the art, such as 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile) and 1,1-azobiscyclohexanecarbonitrile, organic peroxides such as dicumyl peroxide,

Diacyl peroxides, such as dilauroyl peroxide, peroxydicarbonates, such as

Diisopropyl peroxydicarbonate, peresters, such as tert. Butyl peroxy-2-ethylhexanoate, and the like.

For the purposes of the present invention very particularly suitable

Polymerization initiators include in particular the following compounds:

Methyl ethyl ketone peroxide, acetyl acetone peroxide, dilauroyl peroxide, tert-butyl per-2-ethylhexanoate, ketone peroxide, tert-butyl peroctoate, methyl isobutyl ketone peroxide, cyclohexanone peroxide, dibenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxy isopropyl carbonate, 2,5-bis- (2-ethylhexanoyl-peroxy) 2,5-dimethylhexane, tert-butyl peroxy-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, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), 1,1-azobiscyclohexanecarbonitrile, diisopropyl peroxydicarbonate, tert. Amyl peroxypivalate, di (2,4-dichlorobenzoyl) peroxide, tert. Butyl peroxypivalate, 2,2'-azobis (2-amidinopropane) dihydrochloride, di- (3,5,5-trimethylhexanoyl) peroxide, dioctanoyl peroxide, didecanoyl peroxide, 2,2'-azobis (N, N ') dimethyleneisobutyramidine) di (2-methylbenzoyl) peroxide, dimethyl 2,2'-azobisisobutyrate, 2,2'azobis (2-methylbutyronitrile), 2,5-dimethyl-2,5-di- (2-ethylhexanoylperoxy) hexane, 4,4'-azobis (cyanopentanoic) di (4-methylbenzoyl) peroxide, dibenzoyl peroxide, tert.

Amyl peroxy-2-ethylhexanoate, tert. Butyl peroxy-2-ethylhexanoate, tert. Butylperoxy- isobutyrate and mixtures of the aforementioned polymerization initiators.

According to the invention, polymerization initiators having a half-life of 1 hour at a temperature in the range from 25 ° C. to 200 ° C., preferably in the range from 50 ° C. to 150 ° C., in particular in the range from 50 ° C. to 100 ° C., are very particularly preferred , Furthermore, peroxidic polymerization initiators, especially tert-butyl peroctoate, particularly suitable for the present purposes.

The process can be carried out either in the presence or absence of a chain transfer agent. As chain transfer agents, also called molecular weight regulators, it is possible to use typical species described for free-radical polymerizations, as are known to the person skilled in the art.

The sulfur-free molecular weight regulators include, but are not limited to, dimeric α-methylstyrene (2,4-diphenyl-4-methyl-1-pentene), enol ethers of aliphatic and / or cycloaliphatic aldehydes, terpenes, β-terpinene, terpinolene, 1, 4-cyclohexadiene, 1, 4-dihydronaphthalene, 1, 4,5,8-tetrahydronaphthalene, 2,5-dihydrofuran, 2,5-dimethylfuran and / or 3, 6-dihydro-2H-pyran, preferably is dimer a methyl styrene.

As sulfur-containing molecular weight regulators may preferably

Mercapto compounds, dialkyl sulfides, dialkyl disulfides and / or diaryl sulfides are used. The following polymerization regulators are given by way of example: di-n-butyl sulfide, di-n-octyl sulfide, diphenyl sulfide, thiodiglycol, ethylthioethanol, diisopropyl disulfide, di-n-butyl disulfide, di-n-hexyl disulfide, diacetyl disulfide,

Diethanol sulfide, di-t-butyl trisulfide and dimethyl sulfoxide. Preferred as

Molecular weight regulators used compounds are mercapto compounds, dialkyl sulfides, dialkyl disulfides and / or diaryl sulfides. Examples of these

Compounds are ethyl thioglycolate, 2-ethylhexyl thioglycolate,

Pentaerythritol tetrathioglycolate, cysteine, 2-mercaptoethanol, 1, 3-mercaptopropanol, 3-mercaptopropan-1, 2-diol, 1, 4-mercaptobutanol, mercaptoacetic acid, 3-mercaptopropionic acid, thioglycolic acid, mercaptosuccinic acid, thioglycerol, thioacetic acid, thiourea and alkylmercaptans such as Butylmercaptan, n-hexylmercaptan, t-dodecylmercaptan or n-dodecylmercaptan. Particularly preferably used polymerization regulators are mercaptoalcohols and

Mercaptocarboxylic. In the context of the present invention, the

Use of n-dodecylmercaptan and tert-dodecylmercaptan as

Chain transfer agent very particularly preferred. In a particular aspect, the repeating units derived from phosphorus derivatives of a polar ethylenically unsaturated monomer can be produced in the polyalkyl (meth) acrylate by a polymer analogous reaction according to the preparation of a polyalkyl (meth) acrylate set forth above.

Accordingly, first, a polymer having reactive polar units can be prepared wherein the reactive units are reacted with a phosphorus compound of the kind set forth above. The reactive polar units include in particular anhydride or epoxide units.

The reaction of the reactive polar units contained in the polymer, preferably the anhydride or epoxide groups with phosphorus compounds, can usually take place between 25 ° C. and 110 ° C. The phosphorus compound may preferably be in equimolar amount to the reactive polar groups,

preferably the anhydride or epoxide groups are added.

According to a particular aspect of the present invention, it can be provided in the lubricant composition usable according to the invention that the content of polyalkyl (meth) acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom is in the range from 0.1 to 40 Wt .-%, preferably in the range of 0.5 to 30 and particularly preferably in the range of 2 to 15 wt .-%, based on the weight of the lubricant composition.

In a preferred embodiment of the present invention can be used

Lubricant composition is provided that the

Lubricating composition is a phosphorus compound having a

Molecular weight of at most 1000 g / mol, preferably at most 800 g / mol, more preferably at most 600 g / mol.

Here, it is particularly preferable that the phosphorus compound having a molecular weight of at most 1000 g / mol is a phosphoric acid ester

Phosphorsäurethioester, a metal dithiophosphate, a phosphite, a phosphonate, a phosphine or a mixture of these compounds. Examples of preferred phosphorus compounds include

Trialkyl phosphates, triaryl phosphates, e.g. Tricresyl phosphate and especially amine-neutralized mono- and dialkylphosphoric acid esters. These are obtained by reacting phosphoric acid pentaoxide with alcohols, with the remaining

Acid groups in the molecule, which have not reacted despite the excess of the alcohol have been neutralized with long-chain amines. The alkyl and / or aryl groups preferably comprise 1 to 40, preferably 3 to 30 and more preferably 4 to 20 carbon atoms. Alkyl groups of the long-chain amines, with which remaining acid groups of the phosphoric acid derivatives can be reacted, preferably comprise 4 to 40, preferably 6 to 30 and particularly preferably 8 to 20

Carbon atoms.

Thiophosphates are generally obtained by reaction of

Phosphorus pentasulfide with appropriate alcohols. The remaining one

Thiophosphoric acid group is then either with a long-chain amine (= ashless thiophosphate) or a metal salt, for example. Zinc sulfate / hydroxide or molybdenum sulfate / hydroxide reacted. The resulting ash-forming

Zinc-containing wear protection additives are generally referred to as

Zinc dialkyldithiophosphate, short ZnDDP designated.

These additives are available either as individual components or in the form of

Preparations (i.e., mixture with other additives such as antioxidants or detergents) are commercially available, e.g. NA-LUBE AW 61 10 from KING-Industries (wear protection additive) or Additin RC 9200 from Rheinchemie (additive package).

In addition, it is particularly preferred that the weight ratio of polyalkyl (meth) acrylate with repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom to phosphorus compound having a molecular weight of at most 1000 g / mol in the range of 10000: 1 to 1: 10,000, preferably in the range of 500: 1 to 1: 200, and especially preferably in the range of 100: 1 to 1: 1.

Furthermore, it can be used in the invention

Lubricant composition provided that the content of Phosphorus compound having a molecular weight of at most 1000 g / mol in the range of 0.01 to 10 wt .-%, preferably in the range of 0.05 to 8 and particularly preferably in the range of 0.1 to 4, based on the weight of

Lubricant composition is. In addition to the polymers set forth above have the

Lubricating composition of the present invention at least one

Lubricating oil, also called base oil. The lubricating oils include, in particular, mineral oils, synthetic oils and natural oils.

Mineral oils are known per se and commercially available. You will be in

Generally obtained from petroleum or crude oil by distillation and / or refining and optionally further purification and refining processes, wherein the term mineral oil in particular the higher-boiling fractions of crude oil or petroleum fall. 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 air from brown coal and hydrogenation of hard coal or lignite is also possible. Accordingly, mineral oils, depending on the origin of different proportions of aromatic, cyclic, branched and linear hydrocarbons.

In general, one differentiates paraffin-based, naphthenic and aromatic components in crude oils or mineral oils, the terms paraffin-based fraction for longer-chain or highly branched iso-alkanes and naphthenic fraction for

Cycloalkanes are available. In addition, mineral oils, depending on their origin and processing different proportions of n-alkanes, iso-alkanes with a low degree of branching, so-called monomethyl branched paraffins, and compounds with heteroatoms, in particular O, N and / or S, which are polar

Attributes are awarded. The assignment is difficult, however, since individual alkane molecules have long-chain branched groups as well

Cycloalkane and aromatic moieties may have. 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 greater than or equal to 60 wt .-%, preferably greater than or equal to 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.

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%,

low branched alkanes with 18 to 31 C atoms:

1, 0 - 8.0%,

Aromatics with 14 to 32 C atoms:

0.4-10.7%,

Iso- and cycloalkanes with 20 to 32 carbon atoms:

60.7- 82.4%,

polar compounds:

0.1 - 0.8%,

Loss:

6.9 - 19.4%. An improved class of mineral oils (reduced sulfur content, reduced nitrogen content, higher viscosity index, lower pour point) is due to Hydrogen treatment of mineral oils given (hydro isomerization, hydro

Cracking, hydro treatment, hydro finishing). In this case, essentially all aromatic components are reduced in hydrogen presence and naphthenic components are built up.

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 T. Mang, W. Dresel (eds.): "Lubricants and Lubrication", Wiley-VCH, Weinheim 2001; RM Mortier, ST. Orszulik (eds.): "Chemistry and Technology of Lubricants", Blackie Academic & Professional, London, 2 ^nd ed. 1997; or J. Bartz: "Additives for Lubricants", Expert-Verlag, Renningen-Malmsheim 1994. 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 can be used

Origin from gas to liquid (GTL), coal to liquid (CTL) or biomass to liquid (BTL) processes. 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.

Base oils for lubricating oil formulations are grouped according to API (American Petroleum Institute). Mineral oils are divided into Group I (not

Hydrogen-treated) and, depending on the degree of saturation, sulfur content and viscosity index, in Groups II and III (both hydrogen-treated). PAOs are group IV. All other base oils are group V

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

A preferred embodiment of the present invention can be used

Lubricating composition provides that the lubricant composition preferably at least 40 wt .-%, particularly preferably at least 50 wt .-%, especially preferably comprises at least 60% by weight of a base oil. Particularly preferred as the base oil may be a Group I oil, Group II oil, Group III oil or a Polyalphaolefin or a mixture of these oils.

In addition to the components set out above, an inventive

Lubricant composition contain other additives and additives. These include, but are not limited to antiwear AW and extreme pressure EPs such as zinc bis (amyldithiocarbamate) or methylene bis (di-n-butyldithiocarbamate); Sulfur compounds with elemental sulfur and H ₂ S sulphurised hydrocarbons (diisobutylene, terpene);

sulphurised glycerides and fatty acid esters; VI improvers; dispersant;

defoamers; Corrosion inhibitors; Antioxidant and Reibwertveränderer.

Furthermore, it is a particular aspect of the present invention that a

Polyalkyl (meth) acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom, to reduce friction used.

The invention will be explained in more detail below with reference to examples, without this being intended to limit it.

Examples and Comparative Examples:

A possible embodiment of the invention is illustrated in the lower example, without diminishing or limiting the breadth of the invention.

Synthesis according to the invention:

In a reaction flask equipped with heater, internal temperature control, stirrer, nitrogen inlet and condenser, there were added 12.5 g of polymerization oil, 11.18 g of lauryl methacrylate (LMA), 0.51 g of glycidyl methacrylate (GMA) and 0.1 g submitted n-dodecylmercaptan (nDDM) and heated to 100 ° C while introducing nitrogen. After reaching the reaction temperature, the reaction was started by adding 0.1 1 g of tBPO (tert-butyl perbenzoate). At the same time, a mixture consisting of 237.55 g of LMA, 10.23 g of GMA, 2.23 g of nDDM and 0.63 g of tBPO was added uniformly over 3.5 hours. After every 2 and 4 Hours after the end of the feed, another 0.53 g of tBPO was added and stirring was continued for 18 hours. It is then cooled to 30 ° C, 166.07 g

Dilution oil added and 16.61 g DBP (di-n-butyl phosphate) was added dropwise. The mixture was stirred for 1 hour at 30 ° C, then heated to 40 ° C and held at 40 ° C for a further 3 hours. To a complete

The reaction was then heated to 100 ° C and stirred for 12 hours. This gave rise to repeating units derived from phosphorus derivatives of a polar ethylenically unsaturated monomer, the content of these repeating units being about 9.6% by weight. The polymer described above comprised LMA-co-GMA / DBP = 90.4%. 3.9 / 5.7% by weight

Synthesis Comparative Example 1

In a reaction flask equipped with Heater, internal temperature control, stirrer, nitrogen inlet and condenser, 1.124 g

Polymerization oil, 169.41 g LMA (lauryl methacrylate), 54.73 g SMA

(Alkyl methacrylate having 16 to 18 C atoms in the alkyl group), 1.30 g of DPMA (alkyl methacrylate having 12 to 15 C atoms in the alkyl group), 35.18 g

Submitted methyl methacrylate (MMA) and 1, 95 g of nDDM and heated to 1 10 ° C while introducing nitrogen. After reaching the reaction temperature, 0.13 g of a 25% strength solution of tBPO in oil was metered in uniformly over 1 h. Thereafter, 0.65 g of a 25% solution of tBPO was added in a second hour and 1.82 g of the 25% solution of tBPO was added in a third hour. One hour after completion of the feed 0.52 g of tBPO were added and then stirred at 1 10 ° C for 2 h.

The polymer described above comprised LMA-co-SMA-DPMA-MMA = 65-21-0.5-13.5% by weight Synthesis Comparative Example 2

In a reaction flask equipped with heater, internal temperature control, stirrer, nitrogen inlet and condenser, 171.4 g of polymerization oil, 17.8 g of LMA, 1.2 g of DMAEMA and 0.13 g of nDDM were charged and 100 ° while introducing nitrogen C heated up. After reaching the reaction temperature, the reaction was started by adding 0.17 g of tBPO, at the same time a mixture consisting of 357.3 g of LMA, 23.7 g of GMA, 2.67 g of nDDM and 0.95 g of tBPO

evenly dosed within 3.2 hours. 2 and 4 hours after the end of the feed, another 0.80 g of tBPO was added and the mixture was stirred for a further 18 hours.

Subsequently, 228.6 g of diluent oil was added.

After cooling to 40 ° C, 6.0 g of non-neutralized NA-LUBE AW-61 10 are added. After stirring for a further 45 minutes, 6.0 g of the non-neutralized NA-LUBE AW-61 10 (mixture of mono- and di-alkylphosphate with an average of 1.5 acid groups per molecule were repeated.) The alkyl groups are 80% octyl and 20% % Decyl groups). Subsequently, the temperature was gradually increased. After 90 min at 50 ° C. After a further 60 minutes at 60 ° C and then after a further 60 minutes at 70 ° C. At this temperature for a further 15 h was stirred. The polymer described above comprised LMA-co-DMAEMA = 93.8 - 6.2% by weight

Synthesis Comparative Example 3

In a reaction flask equipped with heater, internal temperature control, stirrer, nitrogen inlet and condenser were added 21.6 g of polymerization oil, 241.8 g of LMA, 19.7 g of MOEMA (2-morpholinoethyl methacrylate), 0.5 g of DPMA, 0.5 g SMA and 3.9 g of nDDM and heated to 1 10 ° C while introducing nitrogen. After reaching the reaction temperature, 0.26 g of a 10% solution of tBPO in oil was added uniformly over 1 h. Thereafter, for another hour, 1.31 g of a 10% solution of tBPO and 3.66 in the third hour g of this 10% solution of tBPO added. One and two hours after

Feed ends were added in each case 0.53 g of tBPO and then stirred at 1 10 ° C for 15 h. Thereafter, 236.2 g of diluent oil were added and stirred for an additional hour. 50 g of this polymer solution was transferred to a 100 ml beaker. at

Room temperature are added with stirring (magnetic stirrer with hot plate), 1, 98 g DBP (dibutyl phosphate). This mixture is heated to 60 ° C and stirred for a further 20 min at this temperature.

The polymer described above comprised LMA-co-DPMA-SMA MOEMA = 92.1 -0.2-0.2-7.5 wt%

Methods for Characterizing the Inventive Polymers: a) MTM Measurement (Mini Traction Machine) Friction Value Measurement

Friction measurements were taken on a Mini Traction Machine from PCS

Instruments under the following conditions:

The graphical evaluation of the coefficient of friction measurements is shown in diagram 2. A quantifiable result, where the friction reduction in a number can be expressed, is obtained by integration of the coefficient of friction curves in the range 5 - 2500 mm / s sliding speed. The surface area corresponds to the "total friction" in the entire velocity range investigated The smaller the surface area, the greater the friction-reducing effect of the investigated polymer The determined surface contents are summarized in Table 2. b) Wear test on the 4-bowl apparatus

The shell four-ball apparatus (VKA) is a standardized in DIN 51 350 Part 1 tester for determining the welding and Gutkraft (DIN 51 350 parts 2 and 3) and various friction and wear characteristics of lubricants (DIN 51 350 Part 3 and 5). In the standard test, a rotating ball bearing ball is pressed under load on three similar but stationary balls. The test bench is mainly used in the lubricant industry and is there routinely for

Product development and quality control.

The wear is determined by optical measurement of the resulting dome. From the individual measured calotte diameters, the mean value is formed for the load stage (300N). The final result is the mean

(multiplied by the magnification correction factor of the eyepiece).

Characterization: a) Wear behavior in the VKA test

The polymer according to the invention and those of Comparative Examples 1 and 3 were made into a 13.35% solution in 100N oil (KV100 = 5.30 mm ² / s, 750 ppm phosphorus in solution) and double-weighted at 300N load stage. Table 1: Results of the VKA wear test

When comparing the two polymers, the polymer according to the invention shows a clear improvement in the wear behavior compared to the polymer

Reference polymer. b) friction coefficient measurement

For the friction value measurement, both the polymer according to the invention and the reference polymers 1 and 3 in a mixture of APE Core 80N: APE Core 150N = 70:30 were adjusted to a KV100 of 9.50 mm ² / s. In addition, both were

Measure polymers in the same oil mixture but with the addition of 0.9% by weight of a commercially available, ashless phosphorus-containing wear protection package (AW additive). Table 2: Quantitative evaluation of the coefficients of friction

As can be seen from the measurement of the comparative example, the addition of a wear protection additive usually deteriorates the friction coefficient. By contrast, in the case of the polymer according to the invention, a significant improvement is achieved.

The lubricant composition of the invention is characterized by

defining characterizing features of the appended claims.

Claims

claims

A lubricant composition containing at least one

Polyalkyl (meth) acrylate comprising repeat units derived from

(Meth) acrylates having 6 to 22 carbon atoms in the alcohol radical are derived, characterized in that the polyalkyl (meth) acrylate

Repeating units comprising ethylenically unsaturated

Monomers are derived with at least one covalently bonded phosphorus atom.

A lubricant composition according to claim 1, characterized

characterized in that the lubricant composition is a

Phosphorus compound having a molecular weight of at most 1000 g / mol.

A lubricant composition according to claim 2, characterized

characterized in that the phosphorus compound having a molecular weight of at most 1000 g / mol is a phosphoric acid ester

Phosphoric acid thioester, a metal dithiophosphate, a phosphite

Phosphonate, a phosphine or a mixture of these compounds.

A lubricant composition according to claim 2 or 3, characterized in that the weight ratio of polyalkyl (meth) acrylate with repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom to phosphorus compound having a molecular weight of at most 1000 g / mol in the range of 10000: 1 to 1: 10000.

Lubricating composition according to at least one of

preceding claims 2 to 4, characterized in that the content of phosphorus compound having a molecular weight of at most 1000 g / mol in the range of 0.01 to 10 wt .-%, based on the weight of the lubricant composition. Lubricating composition according to at least one of the preceding claims, characterized in that the

Polyalkyl (meth) acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom comprises from 0.2 to 0.9% by weight of phosphorus atoms, based on the weight of the polyalkyl (meth) acrylate.

Lubricating composition according to at least one of

previous claims, characterized in that the content of polyalkyl (meth) acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom in the range of 0.1 to 40 wt .-%, based on the weight of Lubricant composition is.

Lubricating composition according to at least one of

previous claims, characterized in that the

Polyalkyl (meth) acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom is a random copolymer.

Lubricating composition according to at least one of

previous claims, characterized in that the

Polyalkyl (meth) acrylate having repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom, a weight average molecular weight M _w in the range of 10,000 to 600,000 g / mol.

0. Lubricating composition according to at least one of

previous claims, characterized in that the

Lubricating composition comprises at least 50 wt .-% of a base oil.

1 . A lubricant composition according to claim 10, characterized

in that the base oil is a Group I oil, Group II oil, Group III oil or a polyalphaolefin or a mixture of these oils.

12. Polyalkyl (meth) acrylate suitable for a lubricant composition according to any one of claims 1 to 1 1, comprising

Repeating units derived from (meth) acrylates having 6 to 22

Carbon atoms are derived in the alcohol radical, characterized in that the polyalkyl (meth) acrylate comprises repeating units derived from ethylenically unsaturated monomers having at least one covalently bonded phosphorus atom, and the content of

Phosphorus, based on the weight of the polyalkyl (meth) acrylate, in the range of 0.2 to 0.9 wt .-% is. 13. Polyalkyl (meth) acrylate according to claim 12, characterized in that the polyalkyl (meth) acrylate comprises repeating units derived from

Derived from phosphorus derivatives of a polar ethylenically unsaturated monomer.

14. Polyalkyl (meth) acrylate according to at least one of the preceding

Claims, characterized in that the polar ethylenically unsaturated

Monomer, from which the phosphorus derivative is derived, is a (meth) acrylate having an epoxy group.

15. Polyalkyl (meth) acrylate according to at least one of the preceding

Claims, characterized in that the polyalkyl (meth) acrylate a) comprises 0 to 40 wt .-% of repeating units derived from (meth) acrylates of the formula (I)

wherein R is hydrogen or methyl and R is an alkyl radical having 1 to 5

Carbon atoms, b) comprises from 20 to 99.9% by weight of repeating units derived from

(Meth) acrylates of the formula (II) are derived where R is hydrogen or methyl and R ^{2 is} an alkyl radical having 6 to 22 carbon atoms,

) Comprises 0 to 20% by weight of repeating units derived from (meth) acrylates of the formula (III)

0.1 to 22% by weight of repeating units derived from ethylenic

unsaturated monomers having at least one covalently bound

Are derived from phosphorus atom.

Use of a polyalkyl (meth) acrylate according to any one of the preceding claims 12 to 15 for reducing friction.