EP1134274B1 - Use of carboxylic acids and derivatives thereof as solvent for hydroxyl groups carrying polymers - Google Patents

Abstract

Lubricity additive for fuel oil contains: (A) 10-95 wt.% oil-soluble amphiphilic aliphatic or aromatic amide, (thio)carboxylic, imine and/or (thio)ether compound(s); and (B) 5-90 wt.% copolymer (weight average molecular weight 500-100000 g/mole; hydroxyl (OH) number 10-350 mg KOH/g) of olefinically unsaturated compounds including 5-80 mole-% OH compound(s) and 20-95 mole-% compound(s) with an NOTLESS 6 carbon hydrocarbon chain. Lubricity additive for fuel oil contains: (A) 10-95 wt.% oil-soluble amphiphilic aliphatic or aromatic amide or (thio)carboxylic compound(s) of formula R<1)<C(O)XR<2>)y (I) and/or imine or (thio)ether compound(s) of formula R<1>XR<2> (II); and (B) 5-90 wt.% copolymer(s) with a weight average molecular weight (Mw) of 500-100000 g/mole and hydroxyl (OH) number of 10-350 mg KOH/g, comprising units of (B.1) 5-80 mole % olefinically unsaturated compound(s) with free OH group(s), (B.2) 20-95 mole-% olefinically unsaturated compound(s) with a hydrocarbon chain containing NOTLESS 6 carbon (C) atoms and (B.3) 0-40 mole % comonomer(s) selected from (meth)acrylic acid and esters, vinyl esters and ethers and alkenes. R<1> = 1-50 C (hydroxy)alkyl, alkenyl or aryl; X = NH, NR<3>, O or S; y = 1, 2, 3 or 4; R<2> = hydrogen (H) or 2-10 C hydroxyalkyl; R<3> = N, 2-10 C hydroxyalkyl and/or 1-20 C alkyl; or XR<2> = NR<41>R<42>; R<41> = -(R<43>-NR<44>)m-R<45>; R<42> = -(R<43>-NR<44>)n-R<45>; R<43> = 2-10 C alkylene; R<44> = H, methyl, 2-10 C alkyl, R<1>-CO- or alkoxy; R<45> = H or R<1>-CO-; m, n = 0-20. Independent claims are also included for: (a) fuel oil, comprising a middle distillate containing ≤ 0.05 wt.% sulfur, and 0.001-2 wt.% of the additive; and (b) mixtures of the additive with flow enhancers, comb polymers and/or paraffin dispersants.

Description

The present invention relates to the use of long-chain carboxylic acids and / or derivatives thereof as solvents for hydroxyl-containing polymers.

Mineral oils and mineral oil distillates used as fuel oils generally contain 0.5% by weight and more sulfur which causes the formation of sulfur dioxide upon combustion. In order to reduce the resulting environmental impact, the sulfur content of fuel oils is lowered further and further. The introduction of diesel fuel standard EN 590 currently requires a maximum sulfur content of 350 ppm in Germany. In Scandinavia fuel oils of less than 50 ppm and in exceptional cases less than 10 ppm of sulfur are used. These fuel oils are usually prepared by hydrogenating the fractions obtained from the petroleum by distillation. In the desulfurization but other substances are removed, which give the fuel oils a natural lubricating effect. These substances include polyaromatic and polar compounds.

However, it has now been shown that the friction and wear-reducing properties of fuel oils deteriorate with increasing degree of desulfurization. Often, these properties are so poor that on the lubricated by the fuel materials, such as the distributor injection pumps of diesel engines after a short time must be expected with feeding phenomena. The maximum value set for the 95% distillation point of maximum 360 ° C according to EN 590 since the year 2000 and the further reduction of the 95% distillation point to below 350 ° C and partly below 330 ° C, which has meanwhile been carried out in Scandinavia, further aggravates this problem.

The prior art therefore describes approaches which are intended to provide a solution to this problem (so-called lubricity additives).

EP-A-0 680 506 discloses the use of esters of mono- or polybasic carboxylic acids with mono- or polyhydric alcohols as lubricity-improving additive to fuel oils.

EP-A-0 802 961 discloses fuel oils which contain at least one hydroxyamine to improve their lubricity.

WO 99/36489 discloses the use of mixtures of monomeric and polymeric fatty acids to improve the lubricity of low sulfur middle distillates.

EP-A-0 743 974 discloses the use of mixtures of lubricity additives (esters of polyhydric alcohols and carboxylic acids having 10 to 25 C atoms or dicarboxylic acids) and flow improvers of ethylene / unsaturated ester copolymers for synergistically improving the lubricating effect of highly desulfurized oils ,

EP-A-0 807 676 discloses an additive to fuel oil which increases its lubricity and which comprises, in addition to a carboxylic acid amide, a cold flow improver and an ashless dispersant.

• a) die Ether der Formel 1 entsprechen
  
          R-O-R'     (1),
  
  worin R für lineare oder verzweigte Alkyl- oder Alkenylgruppen mit 4 bis 30 Kohlenstoffatomen und R' für lineare oder verzweigte Alkyl- oder Alkenylgruppen mit 1 bis 30 Kohlenstoffatomen steht
• b) die Ester sich von ein- oder mehrwertigen Carbonsäuren mit 4 bis 30 Kohlenstoffatomen (Säurerest) und von ein- oder mehrwertigen Alkoholen mit 1 bis 30 Kohlenstoffatomen (Alkoholrest) ableiten, oder
• c) die Ether und/oder Ester cyclisch sind, wobei die Ringgröße von 6 bis 30 Kohlenstoffatomen beträgt.

EP-A-0 900 836 discloses an additive for improving the flowability of paraffinic mineral oils and mineral oil distillates containing a mixture of at least one ethylene-vinyl ester co- or terpolymer and at least one paraffin dispersant, characterized in that said mixture is ether and / or ester as a solubilizer contains, wherein

• a) the ethers of formula 1 correspond
  
  RO-R '(1),
  
  wherein R is linear or branched alkyl or alkenyl groups having 4 to 30 carbon atoms and R 'is linear or branched alkyl or alkenyl groups having 1 to 30 carbon atoms
• b) the esters are derived from mono- or polybasic carboxylic acids having 4 to 30 carbon atoms (acid radical) and mono- or polyhydric alcohols having 1 to 30 carbon atoms (alcohol radical), or
• c) the ethers and / or esters are cyclic, the ring size being from 6 to 30 carbon atoms.

Another object of the invention is a process for improving the flowability of mineral oils and mineral oil distillates, characterized in that they are added to the inventive additive.

• A) 10 bis 90 Gew.-% wenigstens eines Copolymers, enthaltend Struktureinheiten, die sich aus Ethylen ableiten und Struktureinheiten, die sich aus olefinisch ungesättigten, hydroxylgruppenhaltigen Verbindungen ableiten, und
• B) 90 bis 10 Gew.-% wenigstens eines Copolymers, enthaltend Struktureinheiten, die sich aus Ethylen ableiten und Struktureinheiten, die sich aus Vinylester, olefinisch ungesättigtem Ether oder Acrylsäureester ableiten.

EP-A-0 960 908 discloses mixtures containing

• A) 10 to 90 wt .-% of at least one copolymer containing structural units derived from ethylene and structural units derived from olefinically unsaturated, hydroxyl-containing compounds, and
• B) 90 to 10 wt .-% of at least one copolymer containing structural units derived from ethylene and structural units derived from vinyl ester, olefinically unsaturated ether or acrylic acid ester.

WO 99/27037 discloses polyalkyl (meth) acrylates (PAMA) functionalized with oxygen containing polar groups and having unexpectedly good CFPP enhancing activity. These are PAMA with hydroxyl-containing and / or ether-containing comonomers such as, for example, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, 2- [2- (2-ethoxyethoxy) ethoxy] -ethyl methacrylate, 2-ethoxyethyl methacrylate, 2-methoxyethyl methacrylate, Methacrylic acid esters of ethoxylated tridecyl alcohol, methacrylic acid esters of methoxypolyethylene glycol, and the corresponding acrylate esters such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate.

The polymeric additives of the prior art, which simultaneously improve the cold flow properties and the lubricity of low-sulfur fuel oils, often have the disadvantage that they must be used as a solution or dispersion in suitable solvents due to their higher viscosity to improve their handling. However, the use of solvents requires increased metering rates and thus the transport of larger amounts of substance.

The object underlying the present invention was thus to find additive compositions which improve the cold flow and lubricating properties of fuel oils and are also effective in small amounts of additive.

Surprisingly, it has been found that oil-soluble amphiphiles are very suitable as solvents for hydroxyl-containing copolymers. In addition, lower dosing rates are required than can be expected from the effectiveness of the components.

worin R¹ einen Alkyl-, Alkenyl-, Hydroxyalkyl- oder aromatischen Rest mit 1 bis 50 Kohlenstoffatomen, X NH, NR³, O oder S, y = 1, 2, 3 oder 4, R² Wasserstoff oder einen Hydroxylgruppen tragenden Alkylrest mit 2 bis 10 Kohlenstoffatomen und R³ einen Stickstoff und/oder Hydroxylgruppen tragenden Alkylrest mit 2 bis 10 Kohlenstoffatomen oder einen C₁-C₂₀-Alkylrest bedeutet, oder XR² gleich NR⁴¹R⁴² bedeutet, worin R⁴¹ ein Rest der Formel 3a

        -(R⁴³-NR⁴⁴)_m-R⁴⁵     (3a)

und R⁴² ein Rest der Formel 3b

        -(R⁴³-NR⁴⁴)_n-R⁴⁵     (3b)

ist, R⁴³ für eine C₂- bis C-₁₀-Alkylengruppe steht, R⁴⁴ Wasserstoff, Methyl, C₂-bis C₁₀-Alkyl, einen Rest der Formel 3c

        R¹-CO-     (3c)

oder einen Alkoxyrest, und R⁴⁵ Wasserstoff oder einen Rest der Formel 3c bedeutet, und m und n jeweils unabhängig voneinander eine ganze Zahl von 0 bis 20 bedeuten,
als Lösungsmittel für Copolymere, welche

• B1) 5 bis 80 mol-% Struktureinheiten, die sich von olefinisch ungesättigten Verbindungen ableiten, welche mindestens eine freie Hydroxylgruppe aufweisen, und
• B2) 20 bis 95 mol-% Struktureinheiten, die sich von olefinisch ungesättigten Verbindungen ableiten, welche einen Kohlenwasserstoffrest mit mindestens 6 Kohlenstoffatomen tragen, sowie gegebenenfalls
• B3) 0 bis 40 mol-% weiterer Struktureinheiten ausgewählt aus der Gruppe bestehend aus (Meth)acrylsäure, (Meth)acrylaten, Vinylestern, Vinylethern und Alkenen, mit der Maßgabe, dass die unter B3) genannten Struktureinheiten von den unter a) und b) genannten Struktureinheiten verschieden sind,

und das Copolymer eine mittlere Molekülmasse Mw von 500 bis 100.000 g/mol und eine OH-Zahl zwischen 10 und 350 mg KOH/g aufweist, und wobei die Menge des Copolymers zwischen 5 und 90 Gew.% bezogen auf das Gewicht der Lösung beträgt.The invention relates to the use of an oil-soluble amphiphile of the formula 1

wherein R ^{1 is} an alkyl, alkenyl, hydroxyalkyl or aromatic radical having 1 to 50 carbon atoms, X is NH, NR ³ , O or S, y = 1, 2, 3 or 4, R ^{2 is} hydrogen or a hydroxyl-bearing alkyl radical 2 to 10 carbon atoms and R ^{3 is} a nitrogen and / or hydroxyl-bearing alkyl radical having 2 to 10 carbon atoms or a C ₁ -C ₂₀ alkyl radical, or XR ² is NR ⁴¹ R ⁴² , where R ^{41 is} a radical of the formula 3a

- (R ⁴³ -NR ⁴⁴ ) _m -R ⁴⁵ (3a)

and R ^{42 is} a radical of formula 3b

- (R ⁴³ -NR ⁴⁴ ) _n -R ⁴⁵ (3b)

R ^{43 is} a C ₂ to C ₁₀ alkylene group, R ^{44 is} hydrogen, methyl, C _{2 to} C ₁₀ alkyl, a radical of the formula 3c

R ¹ -CO- (3c)

or an alkoxy radical, and R ^{45 is} hydrogen or a radical of the formula 3c, and m and n are each independently an integer from 0 to 20,
as a solvent for copolymers which

• B1) from 5 to 80 mol% of structural units derived from olefinically unsaturated compounds having at least one free hydroxyl group, and
• B2) 20 to 95 mol% of structural units derived from olefinically unsaturated compounds which carry a hydrocarbon radical having at least 6 carbon atoms, and optionally
• B3) 0 to 40 mol% of further structural units selected from the group consisting of (meth) acrylic acid, (meth) acrylates, vinyl esters, vinyl ethers and alkenes, with the proviso that the structural units mentioned under B3) of the under a) and b ) are different structural units,

and the copolymer has an average molecular weight Mw of 500 to 100,000 g / mol and an OH number of between 10 and 350 mg KOH / g, and wherein the amount of the copolymer is between 5 and 90 wt% based on the weight of the solution.

The oil-soluble amphiphile (component A) preferably comprises a radical R ¹ having 5 to 40, in particular 12 to 26 carbon atoms. R ¹ is particularly preferably linear or branched and contains 1 to 3 double bonds in the case of linear radicals. The radical R ² preferably has 2 to 8, in particular 2 to 6 carbon atoms and may be interrupted by nitrogen and / or oxygen atoms. In a further preferred embodiment, the sum of the carbon atoms of R ¹ and R ^{2 is} at least 10, in particular at least 15 and at most 35, in particular at most 28 C atoms. In another preferred embodiment, component A carries from 2 to 5 hydroxyl groups, each carbon atom carrying no more than one hydroxyl group.
In a preferred embodiment of the invention, X in formula 1 has the meaning oxygen. These are, in particular, fatty acids and esters between carboxylic acids and dihydric or polyhydric alcohols. Preferred esters contain at least 10, in particular at least 12 carbon atoms. It is also preferred that the esters contain free hydroxyl groups, so the esterification of the polyol with the carboxylic acid is therefore not complete. Suitable polyols are, for example, ethylene glycol, diethylene glycol and higher alkoxylation products, glycerol, trimethylolpropane, pentaerythritol and also sugar derivatives. Other heteroatoms containing polyols such as triethanolamine are suitable.

In a further preferred embodiment of the invention, component A is fatty acids having 10 to 22 C atoms. These can be saturated or unsaturated.

Preferred as component A are straight-chain saturated fatty acids containing up to 18 carbon atoms, such as caprylic acid (octanoic acid), capric acid (decanoic acid), lauric acid (dodecanoic acid), myristic acid (tetradecanoic acid), palmitic acid (hexadecanoic acid), stearic acid (octadecanoic acid) and in particular unsaturated fatty acids, such as Oleic acid (octadecenoic acid), linoleic acid, linolenic acid and mixtures thereof, such as Rapeseed oil acid, soybean fatty acid, sunflower fatty acid, peanut fatty acid and tall oil fatty acid. Furthermore, dimer and oligomer fatty acids, such as those resulting from the oligomerization of unsaturated fatty acids, may be present. Preferably, at least 50%, in particular more than 70%, especially more than 90%, of the fatty acids have at least one double bond.

Also preferred are oil-soluble partial esters of these fatty acids with polyols such as ethylene glycol, diethylene glycol and higher oligomers of alkylene oxides and glycerol, pentaerythritol, sorbitol, diethanolamine, triethanolamine and alkoxylated polyamines. Especially preferred is glycerol monooleate. Particularly preferred are esters which carry at least two free OH groups and an alkyl radical having at least 8 C atoms. The esters preferably have OH numbers between 10 and 200 mg KOH / g, preferably 20 to 150 mg KOH / g.
If X is a nitrogen-containing radical, then reaction products of ethanolamine, diethanolamine, hydroxypropylamine, dihydroxypropylamine, n-methylethanolamine, diglycolamine and 2-amino-2-methylpropanol are suitable. The reaction is preferably carried out by amidation, whereby the resulting amides carry free OH groups. Examples which may be mentioned are fatty acid monoethanolamides, diethanolamides and -N-methylethanolamides. R ³ is preferably methyl and ethyl.

worin R¹ die oben angegebene Bedeutung hat, R⁴¹ einen Rest der Formel 3a

        -(R⁴³-NR⁴⁴)_m-R⁴⁵     (3a)

und R⁴² einen Rest der Formel 3b

        -(R⁴³-NR⁴⁴)_n-R⁴⁵     (3b)

bedeutet, R⁴³ für eine C₂- bis C₁₀-Alkylengruppe steht, R⁴⁴ Wasserstoff, Methyl, C₂- bis C₂₀-Alkyl, einen Rest der Formel 3c

oder einen Alkoxyrest, und R⁴⁵ H oder einen Rest der Formel 3c bedeutet, und m und n jeweils unabhängig voneinander eine ganze Zahl von 0 bis 20 bedeuten, wobei vorzugsweise

• a) m und n nicht gleichzeitig null bedeuten, und
• b) die Summe aus m und n mindestens 1 und höchstens 20 ist.

R⁴³ steht vorzugsweise für einen C₂- bis C₈-, insbesondere für einen C₂- bis C₄-Rest. Das Polyamin, von dem sich die aus R⁴¹, R⁴² und dem sie verbindenden Stickstoffatom gebildete Struktureinheit ableitet, ist vorzugsweise Ethylendiamin, Diethylentriamin, Triethylentetramin, Tetraethylenpentamin oder ein höheres Homologes des Aziridins wie Polyethylenimin, sowie deren Mischungen. Teile der Aminogruppe können alkyliert sein. Ebenfalls geeignet sind Sternamine und Dendrimere. Darunter versteht man Polyamine mit im allgemeinen 2-10 Stickstoffatomen, die über -CH₂-CH₂-Gruppen miteinander verbunden sind und die in randständiger Position mit Acyl- oder Alkylresten abgesättigt sind.
R⁴⁴ steht vorzugsweise für Wasserstoff, einen Acylrest oder für eine Alkoxygruppe der Formel -(OCH₂CH₂)_n-, wobei n eine ganze Zahl zwischen 1 und 10 bedeutet, sowie deren Mischungen.Component A may contain compounds of formula 3.

wherein R ^{1 has} the meaning given above, R ^{41 is} a radical of the formula 3a

- (R ⁴³ -NR ⁴⁴ ) _m -R ⁴⁵ (3a)

and R ^{42 is} a radical of formula 3b

- (R ⁴³ -NR ⁴⁴ ) _n -R ⁴⁵ (3b)

R ^{43 is} a C ₂ - to C ₁₀ -alkylene group, R ^{44 is} hydrogen, methyl, C ₂ - to C ₂₀ -alkyl, a radical of the formula 3c

or an alkoxy radical, and R ^{45 is} H or a radical of the formula 3c, and m and n are each independently an integer from 0 to 20, preferably

• a) m and n do not simultaneously mean zero, and
• b) the sum of m and n is at least 1 and at most 20.

R ⁴³ preferably represents a C ₂ - to C ₈ -, in particular a C ₂ - to C ₄ radical. The polyamine from which the structural unit formed from R ⁴¹ , R ⁴² and the nitrogen atom connecting them is derived is preferably ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or a higher homologue of the aziridine such as polyethyleneimine, and mixtures thereof. Parts of the amino group may be alkylated. Also suitable are star amines and dendrimers. This refers to polyamines having generally 2-10 nitrogen atoms which are connected to each other via -CH ₂ -CH ₂ groups and which are saturated in marginal position with acyl or alkyl radicals.
R ⁴⁴ is preferably hydrogen, an acyl radical or an alkoxy group of the formula - (OCH ₂ CH ₂ ) _n -, where n is an integer between 1 and 10, and mixtures thereof.

worin
R⁴⁶ die Bedeutung von R¹,
R⁴⁷ die Bedeutung von R¹ oder H oder -[CH₂-CH₂-O-]_p-H und
R⁴⁸ die Bedeutung von R² haben können und
p eine ganze Zahl von 1 bis 10 bedeuten,
mit der Maßgabe, dass mindestens einer der Reste R⁴⁶, R⁴⁷ und R⁴⁸ eine OH-Gruppe trägt. Als Beispiel sei y-Hydroxybuttersäuretalgfettamid genannt.
Die Amide werden im allgemeinen durch Kondensation der Polyamine mit den Carbonsäuren oder deren Derivaten wie Estern oder Anhydriden hergestellt. Es werden vorzugsweise 0,2 bis 1,5 mol, insbesondere 0,3 bis 1,2 mol, speziell 1 mol Säure pro Basenäquivalent eingesetzt. Die Kondensation erfolgt bevorzugt bei Temperaturen zwischen 20 und 300°C, insbesondere zwischen 50 und 200°C unter Abdestillieren des Reaktionswassers. Dazu können Lösemittel, bevorzugt aromatische Lösemittel wie Benzol, Toluol, Xylol, Trimethylbenzol und/oder kommerzielle Lösemittelgemische wie z. B. Solvent Naphtha, ^®Shellsol AB, ^®Solvesso 150, ^®Solvesso 200 dem Reaktionsgemisch zugefügt werden. Die Komponente A hat im allgemeinen einen titrierbaren Basenstickstoff von 0,01 - 5 % und eine Säurezahl von weniger als 20 mg KOH/g, vorzugsweise weniger als 10 mg KOH/g.
y nimmt vorzugsweise die Werte 1 oder 2 an. Beispiele bevorzugter Verbindungsgruppen mit y = 2 sind Derivate von Dimerfettsäuren und Alkenylbernsteinsäureanhydriden. Letztere können lineare wie auch verzweigte Alkylreste tragen, d.h. sie können sich von linearen α-Olefinen und/oder von Oligomeren niederer C₃-C₅-Olefine wie Poly(propylen) oder Poly(isobutylen) ableiten.Also suitable as component A are compounds of the formula 3d

wherein
R ^{46 is} the meaning of R ¹ ,
R ^{47 is} the meaning of R ¹ or H or - [CH ₂ -CH ₂ -O-] _p -H and
R ^{48 may have} the meaning of R ² and
p is an integer from 1 to 10,
with the proviso that at least one of R ⁴⁶ , R ⁴⁷ and R ⁴⁸ carries an OH group. An example which may be mentioned is y-hydroxybutyric acid tallow fatty amide.
The amides are generally prepared by condensation of the polyamines with the carboxylic acids or their derivatives such as esters or anhydrides. It is preferably used 0.2 to 1.5 mol, in particular 0.3 to 1.2 mol, especially 1 mol of acid per base equivalent. The condensation is preferably carried out at temperatures between 20 and 300 ° C, in particular between 50 and 200 ° C while distilling off the water of reaction. For this purpose, solvents, preferably aromatic solvents such as benzene, toluene, xylene, trimethylbenzene and / or commercial solvent mixtures such. B. Solvent Naphtha, ^® Shellsol AB, ^® Solvesso 150, ^® Solvesso 200 are added to the reaction mixture. Component A generally has a titratable base nitrogen of 0.01-5% and an acid number of less than 20 mg KOH / g, preferably less than 10 mg KOH / g.
y preferably assumes the values 1 or 2. Examples of preferred compound groups with y = 2 are derivatives of dimer fatty acids and alkenyl succinic anhydrides. The latter can carry linear as well as branched alkyl radicals, ie they can be derived from linear α-olefins and / or from oligomers of lower C ₃ -C ₅ -olefins such as poly (propylene) or poly (isobutylene).

Preferred polyols have 2 to 8 carbon atoms. They preferably carry 2, 3, 4 or 5 hydroxyl groups, but not more than they contain carbon atoms. The carbon chain of the polyols may be straight-chain, branched, saturated or unsaturated and optionally contain heteroatoms. Preferably, it is saturated.

Preferred carboxylic acids, from which the radical R ^{1 is} derived, have 5 to 40, in particular 12 to 30 carbon atoms. Preferably, the carboxylic acid has one or two carboxyl groups. The carbon chain of the carboxylic acids may be straight-chain, branched, saturated or unsaturated. Preferably, more than 50% of the carboxylic acids used (mixtures) contain at least one double bond. Examples of preferred carboxylic acids include caprylic, capric, lauric, myristic, palmitic, stearic, oleic, elaidic, linoleic, linolenic and behenic acids as well as carboxylic acids having heteroatoms such as ricinoleic acid. Furthermore, dimer and trimer fatty acids, as obtainable, for example, by oligomerization of unsaturated fatty acids, and alkenylsuccinic acids can be used.

The copolymer which forms component B of the additive according to the invention contains free OH groups.

In a preferred embodiment of the invention, the copolymer has an OH number of 10 to 300, in particular 20 to 250 mg KOH / g. In a further preferred embodiment, the copolymer has an average molecular weight Mw of 700 to 10,000 g / mol. In a further preferred embodiment the proportion of the structural units (B1) is between 10 and 70 mol%, in particular between 15 and 60 mol%.

The olefinically unsaturated compounds constituting the comonomers (B1) are preferably vinyl esters, acrylic esters, mono- and diesters of ethylenically unsaturated carboxylic acids, methacrylic esters, alkyl vinyl ethers and / or alkenes, the hydroxyalkyl, hydroxyalkenyl, hydroxycycloalkyl or hydroxyaryl radicals wear. These radicals contain at least one hydroxyl group, which may be located anywhere in the radical, but preferably at the chain end (ω-position) or in the para position in ring systems.

The vinyl esters are preferably those of the formula 4

CH ₂ = CH - OCOR ⁴ (4)

wherein R ^{4 is} C ₁ -C ₃₀ -hydroxyalkyl, preferably C ₁ -C ₁₆ -hydroxyalkyl, especially C ₂ -C ₁₂ -hydroxyalkyl, and the corresponding hydroxyoxalkyl radicals. Suitable vinyl esters include 2-hydroxyethyl vinyl ester, α-hydroxypropyl vinyl ester, 3-hydroxypropyl vinyl ester and 4-hydroxybutyl vinyl ester.
The acrylic esters are preferably those of the formula 5

CH ₂ = CR ⁵ - COOR ⁶ (5)

wherein R ^{5 is} hydrogen or methyl and R ^{6 is} C ₁ -C ₃₀ -hydroxyalkyl, preferably C ₁ -C ₁₆ -hydroxyalkyl, especially C ₂ -C ₁₂ -hydroxyalkyl, and the corresponding hydroxyoxalkyl radicals. Suitable acrylic esters include hydroxyethyl acrylate, hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, hydroxyisopropyl acrylate, 4-hydroxybutyl acrylate and glycerol monoacrylate. Equally suitable are the corresponding esters of methacrylic acid, as well as esters of ethylenically unsaturated dicarboxylic acids such as maleic acid, fumaric acid or itaconic acid with diols.

The alkyl vinyl ethers are preferably compounds of the Formula 6

CH ₂ = CH - OR ⁷ (6)

wherein R ^{7 is} C ₁ -C ₃₀ -hydroxyalkyl, preferably C ₁ -C ₁₆ -hydroxyalkyl, especially C ₂ -C ₁₂ -hydroxyalkyl, and the corresponding hydroxyoxalkyl radicals. Suitable alkyl vinyl ethers include 2-hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hexanediol monovinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether and cyclohexanedimethanol monovinyl ether.

The alkenes are preferably monounsaturated hydroxy hydrocarbons having 3 to 30 carbon atoms, especially 4 to 16 carbon atoms and especially 5 to 12 carbon atoms. Suitable alkenes include dimethylvinylcarbinol (= 2-methyl-3-buten-2-ol), allyloxypropanediol, 2-butene-1,4-diol, 1-buten-3-ol, 3-buten-1-ol, 2-butene 1-ol, 1-penten-3-ol, 1-penten-4-ol, 2-methyl-3-buten-1-ol, 1-hexen-3-ol, 5-hexen-1-ol and 7 octene-1,2-diol.

• b1) Vinylester von Carbonsäuren mit mindestens 7 Kohlenstoffatomen, wie z.B. Octylvinylester, 2-Ethylhexylvinylester, Laurinsäurevinylester, Octadecylvinylester, Neononansäurevinylester, Neodecansäurevinylester, Neoundecansäurevinylester.
• b2) (Meth)acrylsäureester mit Alkoholen mit mindestens 6 Kohlenstoffatomen, wie z.B. Octylacrylat, 2-Ethylhexylacrylat, Decylacrylat, Dodecylacrylat, Tetradecylacrylat, Hexadecylacrylat, sowie die entsprechenden Ester der Methacrylsäure und Ester von ethylenisch ungesättigten Dicarbonsäuren wie Maleinsäure, Fumarsäure oder Itaconsäure
• b3) Alkylvinylether, die mindestens einen C₆-Alkylrest tragen, wie z.B. Octadecylvinylether
• b4) Olefine und Vinylaromaten mit Kettenlängen von mindestens 6 Kohlenstoffatomen, wie z.B. 1-Octen, 1-Decen, 1-Dodecen, 1-Tetradecen, 1-Hexadecen, 1-Octdecen, 1-Eicosen, technische ∀-Olefinschnitte, wie C₂₀-C₂₄-∀-Olefin, C₂₄-C₂₈-∀-Olefin, C₃₀₊-∀-Olefin, Styrol, ∀-Methylstyrol, p-Methoxystyrol.

Preferred comonomers (B2) are olefinically unsaturated compounds which carry hydrocarbon radicals having at least 6 C atoms (excluding the olefinic group required for the polymerization). These hydrocarbon radicals can be linear, branched, cyclic and / or aromatic. In addition to hydrocarbon groups, they can also carry minor amounts of further functional groups with heteroatoms, such as nitro, halogen, cyano, amino groups, provided that they do not affect the oil solubility. These are preferably monomers from the following groups:

• b1) vinyl esters of carboxylic acids having at least 7 carbon atoms, such as octylvinyl, 2-ethylhexylvinyl, lauric, octadecyl, neononanoic, vinyl, neodecanoic, vinyl
• b2) (meth) acrylic acid esters with alcohols having at least 6 carbon atoms, such as octyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, dodecyl acrylate, tetradecyl acrylate, hexadecyl acrylate, and the corresponding esters of Methacrylic acid and esters of ethylenically unsaturated dicarboxylic acids such as maleic acid, fumaric acid or itaconic acid
• b3) alkyl vinyl ethers which carry at least one C ₆ -alkyl radical, for example octadecyl vinyl ether
• b4) Olefins and vinylaromatics having chain lengths of at least 6 carbon atoms, such as 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octdecene, 1-eicosene, technical ∀-Olefinschnitte, such as C ₂₀ -C _24- ∀-olefin, C ₂₄ -C ₂₈ ∀-olefin, C ₃₀₊ ∀-olefin, styrene, ∀-methylstyrene, p-methoxystyrene.

Both individual comonomers B2 and mixtures of different comonomers of the individual and / or different monomers b1) to b4) can be used. Particularly preferred comonomers B2 are the abovementioned olefinically unsaturated compounds of groups b1) to b4) having hydrocarbon radicals which comprise at least 8 carbon atoms. Preferably, at least 10 mol%, preferably at least 25 mol%, in particular more than 50 mol% of the monomers B2 bear linear hydrocarbon radicals. The proportion of comonomers B2 in the polymers according to the invention is preferably between 30 and 90 mol%, in particular between 40 and 80 mol%.

• a) Alkylaminoacrylate bzw. -methacrylate, wie z.B. Aminoethylacrylat, Aminopropylacrylat, Amino-n-butylacrylat, N-Methylaminoethylacrylat, N,N-Dimethylaminoethylacrylat, N,N-Diethylaminoethylacrylat,
  N,N-Dimethylaminopropylacrylat, N,N-Diethylaminopropylacrylat sowie die entsprechenden Methacrylate,
• b) Alkylacrylamide und -methacrylamide, wie z.B. Ethylacrylamid, Butylacrylamid, N-Octylacrylamid, N-Propyl-N-methoxyethylacrylamid, N-Acryloylphthalimid, N-Acryloylsuccinimid, N-Methylolacrylamid, sowie die entsprechenden Methacrylamide,
• c) Vinylamide, wie z.B. N-Vinyl-N-methylacetamid, N-Vinylsuccinimid,
• d) Aminoalkylvinylether, wie z.B. Aminopropylvinylether, Diethylaminoethylvinylether, Dimethylaminopropylvinylether,
• e) Allylamin, N-Allyl-N-methylamin, N-Allyl-N-ethylamin, Diallylamin
• f) eine Vinylgruppe tragende Heterozyklen, wie z.B. N-Vinylpyrrolidon, Methylvinylimidazol, 2-Vinylpyridin, 4-Vinylpyridin, 2-Methyl-5-vinylpyridin, Vinylcarbazol, Vinylimidazol, N-Vinyl-2-piperidon, N-Vinylcaprolactem.

As further comonomers B3 optionally up to 40 mol% of acrylic acid or methacrylic acid, acrylates such as methacrylate, ethyl acrylate, butyl acrylate, and the corresponding methacrylic esters, vinyl esters such as vinyl acetate, vinyl propionate, hexylvinyl, olefins such as ethylene, propene, butene, isobutene, pentene, hexene , 4-methylpentene, diisobutylene, norbornene. Likewise, nitrogen-containing monomers such as

• a) alkylaminoacrylates or methacrylates, such as, for example, aminoethyl acrylate, aminopropyl acrylate, amino-n-butyl acrylate, N-methylaminoethyl acrylate, N, N-dimethylaminoethyl acrylate, N, N-diethylaminoethyl acrylate,
  N, N-dimethylaminopropyl acrylate, N, N-diethylaminopropyl acrylate and the corresponding methacrylates,
• b) alkylacrylamides and -methacrylamides, such as ethylacrylamide, butylacrylamide, N-octylacrylamide, N-propyl-N-methoxyethylacrylamide, N-acryloylphthalimide, N-acryloylsuccinimide, N-methylolacrylamide, and the corresponding methacrylamides,
• c) vinylamides, such as N-vinyl-N-methylacetamide, N-vinylsuccinimide,
• d) aminoalkyl vinyl ethers, such as, for example, aminopropyl vinyl ether, diethylaminoethyl vinyl ether, dimethylaminopropyl vinyl ether,
• e) allylamine, N-allyl-N-methylamine, N-allyl-N-ethylamine, diallylamine
• f) a vinyl group-bearing heterocycles such as N-vinylpyrrolidone, methylvinylimidazole, 2-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, vinylcarbazole, vinylimidazole, N-vinyl-2-piperidone, N-vinylcaprolactam.

To achieve easier handling and better solubility of the additives, preferably up to 20 mol%, in particular up to 10 mol%, of the comonomers B2 and optionally B3 contain branched alkyl chains. Oligomers and polymers of lower olefins, e.g. Poly (propylene), poly (butene) and poly (isobutylene) suitable, with those oligomers having a high proportion of terminal double bonds (> 50 mol%, preferably> 70 mol%, in particular> 75 mol%) are preferred.

The melt viscosities of the copolymers at 140 ° C. are preferably below 10,000 mPas, in particular between 10 and 2000 mPas and especially between 15 and 1000 mPas. For the purposes of the invention, oil-soluble means that at least 10% by weight, preferably at least 1% by weight, in particular at least 0.1% by weight, of the additive becomes clearly soluble in the middle distillate to be added.

The copolymers which form the constituent B of the additive according to the invention can be prepared by direct polymerization of compounds which are as specified Structural units are obtained. It is also possible to prepare them by a polymer-analogous reaction.

For this it is necessary to produce a polymer with free acid groups. These originate from the copolymerization of an olefinically unsaturated carboxylic acid or such a derivative of a carboxylic acid with the other comonomers B1 and optionally B2 defined here. These carboxylic acids and carboxylic acid derivatives are preferably maleic acid, acrylic acid, methacrylic acid, fumaric acid or itaconic acid, and derivatives thereof. In a polymer-analogous reaction, the monomers B1 carrying hydroxyl groups are prepared therefrom.

As derivatives of the carboxylic acids, their anhydrides are preferred. Particularly preferred is maleic anhydride. For copolymers of maleic anhydride (MSA) with α-olefins, alternating copolymers containing about 40 to 60 mole percent MSA and 60-40 mole percent α-olefin are preferred.

To prepare the copolymers according to the invention by means of polymer-analogous reaction, the polymeric acid groups are reacted with at least bifunctional reagents which carry at least one OH function. Binding to the polymer can be effected via hydroxy groups as esters and / or via primary or secondary amino groups in the form of amides, imides and / or ammonium salts. To avoid crosslinking reactions, it is possible, for example, to work with an excess of bifunctional reagent and / or in high dilution. The esterification, amidation or imidization is usually carried out under elimination of water of reaction (azeotropic distillation, expulsion with gas stream such as N ₂ ). The residual acid number is set to values <150, preferably <20, in particular <10 mg KOH / g. Suitable reagents are, for example: ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, trimethylolpropane, mixed alkoxylates of ethylene oxide, propylene oxide and / or butylene oxide with up to 50 units, in particular up to 10 units derived from ethylene oxide, propylene oxide and / or butylene oxide, glycerol, pentaerythritol, sorbitol, Ethanolamine, diethanolamine, triethanolamine, butyldiethanolamine, methyldiisopropylamine, aminopropanediol and alkoxylated Polyamines. The latter can be derived, for example, from ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine and their higher homologs, which are alkoxylated with from 0.5 to 50, in particular 10, mol of ethylene oxide, propylene oxide and / or butylene oxide per H atom bonded to an N atom , The reaction with the polymer can be carried out both via an OH group to the ester as well as via a primary or secondary amino group to the amide or imide.

The reaction of the acid group-containing copolymers takes place between 30 and 250 ° C in the course of 0.5 to 20 hours. The hydroxy-functional reagent is reacted with amounts of from about 1 to about 2 mol per mol of polymerized-in derivative (derivative).
In order to set a lower OH number for a given base polymer and thus to improve the oil solubility, up to 50 mol% of the hydroxy-functional reagent can be replaced by alkylamines and / or alcohols having up to 24 carbon atoms.

Furthermore, the copolymers B can be obtained by alkoxylating the acid group-containing copolymers. Copolymers suitable for this purpose are, for example, those of acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid or maleic anhydride with the comonomers B2 and optionally B3. These are oxalkylated on the acid groups with C ₁ - to C ₁₀ -alkylene oxides. Preferred alkylene oxides are ethylene oxide, propylene oxide and butylene oxide. The alkoxylation is preferably carried out with a use of 0.5 to 10 mol, in particular 1 to 5 mol and especially 1 to 2 mol of alkylene oxide per mol of acid group.

The copolymerization of the comonomers is carried out by known batchwise or continuous polymerization processes (cf., for example, Ullmanns Encyclopadie der Technischen Chemie, 5th edition, Vol. A21, pages 305 to 413). The polymerization in solution, in suspension, in the gas phase and the precipitation and bulk polymerization are suitable. Preference is given to bulk and solution polymerization. The reaction of the comonomers is by radicals forming initiators (radical chain starter) initiated. This class of substances includes, for example, oxygen, hydroperoxides, peroxides and azo compounds such as cumene hydroperoxide, t-butyl hydroperoxide, dilauroyl peroxide, dibenzoyl peroxide, bis (2-ethylhexyl) peroxydicarbonate, t-butyl permalate, t-butyl perpivalate, t-butyl perbenzoate, dicumyl peroxide, t-butylcumyl peroxide, Di (t-butyl) peroxide, 2,2'-azobis (2-methylpropanonitrile), 2,2'-azobis (2-methylbutyronitrile). The initiators are used individually or as a mixture of two or more substances in amounts of 0.01 to 20 wt .-%, preferably 0.05 to 10 wt .-%, based on the comonomer mixture.

The polymerization is generally carried out at temperatures of 40-300 ° C, preferably at 80-250 ° C, which is advantageously carried out under pressure when using monomers and / or solvents having boiling temperatures below the polymerization temperature. The polymerization is conveniently carried out under exclusion of air, e.g. carried out under nitrogen, since oxygen interferes with the polymerization. When choosing the initiator or the initiator system, it is expedient to ensure that the half-life of the initiator or initiator system is less than 3 hours at the selected polymerization temperature. It is preferably between 0.5 minutes and one hour.

The desired molecular weight of the copolymers is obtained with a given composition of the comonomer mixture by varying the reaction parameters concentration and temperature. To obtain low molecular weight copolymers can continue to work with the addition of moderators. Suitable molecular weight regulators are, for example, aldehydes, ketones, alcohols and organic sulfur compounds such as mercaptoethanol, mercaptopropanol, mercaptoacetic acid, mercaptopropionic acid, tert-butylmercaptan, n-butylmercaptan, n-octylmercaptan, tert-dodecylmercaptan and n-dodecylmercaptan. Depending on the desired viscosity, the moderators are used in amounts of up to 20% by weight, preferably 0.05 to 10% by weight, based on the comonomer mixture.

Apparatuses suitable for the polymerization are e.g. conventional stirred tank with, for example, anchor, blade, impeller or multi-stage pulse countercurrent stirrer and for continuous production stirred tank cascades, stirred reactors or static mixer.

Preferred method for the preparation of the copolymers is in addition to the solvent-free bulk polymerization solution polymerization. It is carried out in solvents in which the monomers and the copolymers formed are soluble. All solvents are suitable for this purpose which fulfill this requirement and which do not react with the monomers and the copolymers formed. These are, for example, organic, preferably aromatic solvents, such as cumene, toluene, xylene, ethylbenzene or else commercial solvent mixtures, such as ^® Solvent Naphtha, ^® Shellsol AB or ^® Solvesso 150, 200.

In the preparation of all monomers can be submitted and polymerized by the addition of a free radical initiator and heat.

Conveniently, however, the solvent and optionally a portion of the monomers (for example about 5 to 20%) are initially charged and the remainder of the monomer mixture is metered in with the initiator and optionally co-initiator and regulator.

The concentration of the monomers to be polymerized is between 20 and 95 wt .-%, preferably 50 and 90 wt .-%.

The solid copolymer can be isolated by precipitation with suitable non-solvents such as acetone or methanol or by evaporation of the solvent. However, it is expedient to choose a solvent for the polymerization in which the polymer can be used directly according to the invention.

The additives are preferably added to the mineral oils or mineral oil distillates as a mixture, the oil-soluble amphiphile A serving as a solvent for the copolymer B. Preferred mixtures are at temperatures below 40 ° C flowable, ie they have at this temperature a viscosity of less than 10 Pas, in particular <1 Pas. In the case of a viscosity which is too high for the processing and / or the self-sticking point of the mixture, up to 50% by weight, in particular up to 20% by weight, based on the additive of a solvent, may be added. Solvents may be aliphatic and / or aromatic hydrocarbons. The advantages of the additive combination can also be used with separate metering of components A and B.

Mineral oils or mineral oil distillates improved by the additives in their lubricating and / or cold-flow properties contain from 0.001 to 2, preferably from 0.005 to 0.5,% by weight of additive based on the distillate.
The additives can furthermore be used in the form of mixtures which consist of additives of the claimed type but of different qualitative and / or quantitative composition. The mixing ratio (in parts by weight) of the additive components can be varied over a wide range and, for example, 20: 1 to 1:20, preferably 10: 1 to 1:10 amount. In this way, the additives can be tailored to individual requirements.

For the preparation of additive packages for specific problem solutions, the additives can also be used together with one or more oil-soluble co-additives, which in themselves improve the cold flow properties and / or lubricity of crude oils, lubricating oils or fuel oils. Examples of such co-additives are vinyl acetate-containing copolymers or terpolymers of ethylene, polar compounds which effect a paraffin dispersion (paraffin dispersants), comb polymers, alkylphenol-aldehyde resins and oil-soluble amphiphiles.

For example, mixtures of the additives with copolymers which contain from 10 to 40% by weight of vinyl acetate and from 60 to 90% by weight of ethylene have proved to be outstanding. According to a further embodiment of the invention, the additives are used in admixture with ethylene / vinyl acetate / vinyl neononanoate terpolymers or ethylene vinyl acetate / vinyl neodecanoate terpolymers to improve the flowability of mineral oils or mineral oil distillates. The terpolymers of Vinyl neononanoate or vinyl neodecanoate contain, in addition to ethylene, 10 to 35% by weight of vinyl acetate and 1 to 25% by weight of the respective neo compound. Further preferred copolymers contain, in addition to ethylene and from 10 to 35% by weight of vinyl esters, from 0.5 to 20% by weight of olefin, such as diisobutylene, 4-methylpentene or norbornene. The mixing ratio of the additives with the ethylene / vinyl acetate copolymers described above or the terpolymers of ethylene, vinyl acetate and the vinyl esters of neononanic or neodecanoic acid is (in parts by weight) 20: 1 to 1:20, preferably 10: 1 to 1 : 10th

For use as flow improver and / or lubricity additive, the additives may also be used in admixture with paraffin dispersants. Paraffin dispersants reduce the size of the paraffin crystals and cause the paraffin particles to not settle but remain colloidally dispersed with significantly reduced sedimentation effort. Furthermore, they increase the lubricity of the additives of the invention. As paraffin dispersants, oil-soluble polar compounds having ionic or polar groups, e.g. Amine salts and / or amides which are obtained by reaction of aliphatic or aromatic amines, preferably long-chain aliphatic amines, with aliphatic or aromatic mono-, di-, tri- or tetracarboxylic acids or their anhydrides are proven (compare US 4 211 534). Other paraffin dispersants are copolymers of maleic anhydride and α, β-unsaturated compounds which can optionally be reacted with primary monoalkylamines and / or aliphatic alcohols (cf., EP 0 154 177), the reaction products of alkenyl spiro-bis-lactones with amines (cf., EP 0 413 279 B1 ) and EP 0 606 055 A2 reaction products of terpolymers based on α, β-unsaturated dicarboxylic anhydrides, α, β-unsaturated compounds and polyoxyalkylene ethers of lower unsaturated alcohols. Alkylphenol-aldehyde resins are also suitable as paraffin dispersants.

worin R⁶ für C₄-C₅₀-Alkyl oder -Alkenyl, R⁷ für Ethoxy- und/oder Propoxy,
n für eine Zahl von 5 bis 100 und p für eine Zahl von 0 bis 50 steht.Thus, the additives can be used in mixture with alkylphenol-formaldehyde resins. In a preferred embodiment of the invention, these alkylphenol-formaldehyde resins are those of the formula 7

in which R ^{6 is} C ₄ -C ₅₀ -alkyl or -alkenyl, R ^{7 is} ethoxy- and / or propoxy,
n is a number from 5 to 100 and p is a number from 0 to 50.

Finally, in another embodiment of the invention, the additives are used together with comb polymers. This term refers to polymers in which hydrocarbon radicals having at least 8, in particular at least 10, carbon atoms are bonded to a polymer backbone. Preferably, they are homopolymers whose alkyl side chains contain at least 8 and in particular at least 10 carbon atoms. In the case of copolymers, at least 20%, preferably at least 30% of the monomers have side chains (compare Comb-like Polymers-Structure and Properties, NA Platé and VP Shibaev, J. Polym, Sci Macromolecular Revs 1974, 8, 117 ff). Examples of suitable comb polymers are, for example, fumarate / vinyl acetate copolymers (cf., EP 0 153 176 A1), copolymers of a C ₆ - to C ₂₄ -α-olefin and an NC ₆ - to C ₂₂ -alkylmaleimide (compare EP 0 320 766), further esterified olefin / maleic anhydride copolymers, polymers and copolymers of α-olefins, and esterified copolymers of styrene and maleic anhydride.

beschrieben werden. Darin bedeuten

A

R', COOR', OCOR', R"-COOR' oder OR';

D

H, CH₃, A oder R;

E

H oder A;

G

H, R", R"-COOR', einen Arylrest oder einen heterocyclischen Rest;

M

H, COOR", OCOR", OR" oder COOH;

N

H, R", COOR", OCOR, COOH oder einen Arylrest;
R' eine Kohlenwasserstoffkette mit 8-150 Kohlenstoffatomen;
R" eine Kohlenwasserstoffkette mit 1 bis 10 Kohlenstoffatomen;

m

eine Zahl zwischen 0,4 und 1,0; und

n

eine Zahl zwischen 0 und 0,6.

Comb polymers can be obtained, for example, by the formula 8

to be discribed. Mean in it

A

R ', COOR', OCOR ', R "-COOR' or OR ';

D

H, CH _3, A or R;

e

H or A;

G

H, R ", R" -COOR ', an aryl radical or a heterocyclic radical;

M

H, COOR ", OCOR", OR "or COOH;

N

H, R ", COOR", OCOR, COOH or an aryl radical;
R 'is a hydrocarbon chain of 8-150 carbon atoms;
R "is a hydrocarbon chain of 1 to 10 carbon atoms;

m

a number between 0.4 and 1.0; and

n

a number between 0 and 0.6.

The mixing ratio (in parts by weight) of the additives according to the invention with paraffin dispersants, resins or comb polymers is in each case 1:10 to 20: 1, preferably 1: 1 to 10: 1.
additives according to the invention are particularly suitable for improving the lubricating properties of animal, vegetable or mineral oils. In addition, they simultaneously improve the cold flow properties of the additized oils. They are particularly well suited for use in middle distillates. As middle distillates are in particular those mineral oils which are obtained by distillation of crude oil and boil in the range of 120 to 450 ° C, for example kerosene, jet fuel, diesel and fuel oil. Preferably, the additives are used in such middle distillates that
0.05% by weight of sulfur and less, more preferably less than 350 ppm of sulfur, especially less than 200 ppm of sulfur and in special cases less than 50 ppm of sulfur. These are generally those middle distillates that have been subjected to a hydrogenating refining, and therefore contain only small amounts of polyaromatic and polar compounds that give them a natural lubricating effect. The additives are further preferably used in such middle distillates having 95% distillation points below 370 ° C, especially 350 ° C and in special cases below 330 ° C. They can also be used as components in lubricating oils.

The additives can be used alone or together with other additives, e.g. with other pour point depressants or dewaxing aids, with corrosion inhibitors, antioxidants, sludge inhibitors, dehazers, and cloud point depressant additives.

The effectiveness of the additives as lubricity additives is further illustrated by the following examples.

Examples

The determination of the hydroxy-functional comonomers is carried out by determining the OH number by reaction of the polymer with excess acetic anhydride and subsequent titration of the acetic acid formed with KOH.

The viscosity is determined in accordance with ISO 3219 (B) using a rotary viscometer (Haake RV 20) with a plate-and-cone measuring system. Table 1: Characterization of the hydroxy-functional copolymers template copolymer A1 Copolymer of 50 mol% hydroxyethyl methacrylate and 50 mol% octadecene having a melt viscosity at 140 ° C of 70 mPas and an OH number of 185 mg KOH / g. A2 Copolymer of 25 mol% hydroxybutyl vinyl ether and 75 mol% octadecyl vinyl ether having a melt viscosity at 140 ° C of 54 mPas and an OH number of 70 mg KOH / g A3 Terpolymer of 18 mol% ethylene glycol monovinyl ether, 67 mol% Ooctadecylacrylat and 15 mol% vinyl acetate having a melt viscosity at 140 ° C of 82 mPas and an OH number of 35 mg KOH / g. A4 Terpolymer of 50 mol% maleic anhydride, 25 mol% tetradecene and 25 mol% hexadecene having a melt viscosity at 160 ° C of 50 mPas, esterified with diethylene glycol. The OH number is 225 mg KOH / g template B1 oleic acid B2 tall oil fatty acid B3 Glycerol monooleate B4 Poly (isobutenyl) succinic anhydride, doubly esterified with diethylene glycol according to Example 1 of WO 97/45507 B5 oleic acid diethanolamide

Table 3: Characterization of the test oils

The boiling characteristics are determined according to ASTM D-86, the CFPP value according to EN 116 and the determination of the cloud point according to ISO 3015. Test oil 1 Start of boiling [° C] 185 20% [° C] 201 30% [° C] 207 90% [° C] 289 95% [° C] 305 Cloud Point [° C] -27 CFPP [° C] -30 S content [ppm] 13 Density [g / cm ³ ] 0,817 WS 1.4 [μm] 676

Lubricating effect in middle distillates

The lubricating effect of the additives was carried out by means of an HFRR instrument from PCS Instruments on additized oils at 60 ° C. The High Frequency Reciprocating Rig Test (HFRR) is described in D. Wei, H. Spikes, Wear, Vol. 2, p. 217, 1986. The results are reported as Wear Scar (WS 1.4). A low Wear Scar shows a good lubricating effect. Table 4: Wear Scar in test oil 2 example additive Wear Scar 1.4 μm 1 200 ppm (A1 + B1 / 1: 1) 334 μm 2 250 ppm (A1 + B3 / 2: 1) 290 μm 3 200 ppm (A2 + B2 / 1: 1) 310 μm 4 150 ppm (A2 + B5 / 1: 1) 370 μm 5 175 ppm (A3 + B2 / 1: 2) 380 μm 6 250ppm (A3 + B4 / 2: 1) 385 μm 7 300 ppm (A4 + B1 / 3: 1) 355 μm 8 (Cf.) 350 ppm (A1 in solvent naphtha / 1: 1) 410 μm 9 (Cf.) 500 ppm (A2 in solvent naphtha / 1: 1) 480 μm 10 (Cf.) 500 ppm (A3 in solvent naphtha / 1: 1) 420 μm 11 (Cf.) 400 ppm (A4 in solvent naphtha / 1: 1) 224 μm 12 (Cf.) 150 ppm B1 435 μm 13 (Cf.) 150 ppm B2 449 μm 14 (Cf.) 150 ppm B3 389 μm 15 (Cf.) 150 ppm B4 460 μm 16 (Cf.) 125 ppm B5 470 μm

Claims (7)

1. The use of an oil-soluble amphiphile of the formula 1

   

   in which R¹ is an alkyl, alkenyl, hydroxyalkyl or aromatic radical having 1 to 50 carbon atoms, X is NH, NR³, O or S, y is 1, 2, 3 or 4, R² is hydrogen or an alkyl radical carrying hydroxyl groups and having 2 to 10 carbon atoms and R³ is an alkyl radical carrying nitrogen and/or hydroxyl groups and having 2 to 10 carbon atoms or a C₁-C₂₀-alkyl radical, or XR² is NR⁴¹R⁴², in which R⁴¹ is a radical of the formula 3a
   
           -(R⁴³-NR⁴⁴)_m-R-⁴⁵     (3a)
   
   and R⁴² is a radical of the formula 3b
   
           -(R⁴³-NR⁴⁴)_nR⁴⁵     (3b),
   
   R⁴³ is a C₂- to C₁₀-alkylene group, R⁴⁴ is hydrogen, methyl, C₂- to C₁₀-alkyl, a radical of the formula 3c
   
           R¹-CO-     (3c)
   
   or an alkoxy radical, and R⁴⁵ is hydrogen or a radical of the formula 3c, and m and n, in each case independently of one another, are an integer from 0 to 20,
   as solvent for copolymers which contain

   B1) from 5 to 80 mol% of structural units which are derived from olefinically unsaturated compounds which have at least one free hydroxyl group, and

   B2) from 20 to 95 mol% of structural units which are derived from olefinically unsaturated compounds which carry a hydrocarbon radical having at least 6 carbon atoms, and, if required,

   B3) from 0 to 40 mol% of further structural units selected from the group consisting of (meth)acrylic acid, (meth)acrylates, vinyl esters, vinyl ethers and alkenes, with the proviso that the structural units stated under B3) differ from the structural units stated under a) and b),

   and the copolymer has an average molar mass Mw of from 500 to 100,000 g/mol and an OH number of from 10 to 350 mg KOH/g, and in which the amount of the copolymer is from 5 to 90% by weight, based on the weight of the solution.
2. The use as claimed in claim 1, the copolymer B having an OH number of from 20 to 250 mg KOH/g.
3. The use as claimed in claims 1 and/or 2, the copolymer having an average molecular weight Mw of from 700 to 10,000 g/mol.
4. The use as claimed in one or more of claims 1 to 3, the proportion of structural units B1 being from 10 to 70 mol%.
5. The use as claimed in one or more of claims 1 to 4, the proportion of the comonomers B2 in the polymers being from 30 to 90 mol%.
6. The use as claimed in one or more of claims 1 to 5, up to 20 mol%, preferably up to 10 mol%, of the comonomers B2 and, if required, B3 containing branched alkyl chains.
7. The use as claimed in one or more of claims 1 to 6, the oil-soluble amphiphile being a fatty acid having 10 to 18 carbon atoms, or an ester derived from such a fatty acid.