EP2162512A1 - Detergent additive-containing mineral oils having improved cold flow properties - Google Patents

Abstract

The invention relates to the use of at least one oil-soluble compound B) which acts as a nucleating agent for paraffin crystallization and which is selected from substantially linear hydrocarbons with at least 22 C atoms, for improving the response of cold flow improvers for mineral oils C) in middle distillates that contain at least one ashless, nitrogenous detergent additive A), which is an oil-soluble, amphiphilic compound that comprises at least one alkyl or alkenyl group bound to a polar group, said alkyl or alkenyl group having 10 to 500 C atoms and the polar group having 2 or more nitrogen atoms.

Description

 description

Detergent additives containing mineral oils with improved cold flowability

The present invention relates to the use of nucleating agents to improve the cold flowability of mineral oil distillates containing detergent additives, as well as the mineral oil distillates additive.

Increasingly stringent environmental legislation requires ever more sophisticated engine technology to comply with established emission limits. However, occupying engine parts such as the combustion residue valves changes the characteristics of the engine and results in increased emissions as well as increased consumption. Therefore, motor fuels are added to detergent additives which remove such deposits or prevent their formation. These are generally oil-soluble amphiphiles which contain a polar head group in addition to an oil-soluble, temperature-stable hydrophobic radical.

On the other hand, in the course of decreasing world oil reserves, increasingly heavier and thus paraffin-rich crude oils are extracted and processed, which consequently also lead to paraffin-rich fuel oils. The paraffins contained in particular in middle distillates can crystallize on lowering the temperature of the oil and partially agglomerate with the inclusion of oil. This crystallization and agglomeration can cause blockages of the filters in engines and firing systems, especially in winter, which prevents safe metering of the fuels and may possibly lead to a complete interruption of the fuel supply. The paraffin problem is also exacerbated by the environmental reasons to reduce the sulfur content increasing hydrodesulfurization of fuel oils, which leads to an increased proportion of cold-critical paraffins in the fuel oil. In order to improve the cold flow properties, middle distillates are often added with chemical additives, so-called cold flow improvers or flow improvers, which modify the crystal structure and agglomeration tendency of the precipitated paraffins, so that the oils thus added can still be pumped or used at temperatures which are often more than 20 ^° C. lower than non-additized oils. As the cold flow improver, oil-soluble copolymers of ethylene and unsaturated esters, oil-soluble polar nitrogen compounds and / or comb polymers are usually used. In addition, however, other additions have been proposed.

As engine technology becomes ever more demanding, as well as increasing demands on the environmental performance of fuel oils and their combustion products, detergent additives are being developed with ever increasing effectiveness. In addition, they are often used in very high dosage rates. It is reported that this reduces, for example, in diesel fuels, the specific consumption and the performance of the engines is increased. However, these additives often have negative effects on the cold flowability of middle distillates and in particular on the efficacy of known cold flow improvers. Especially with middle distillates with low boiling point and simultaneously low aromatic content, it is often difficult or even impossible to adjust in the presence of modern detergent additives using conventional flow improvers a satisfactory cold flow behavior. For example, the addition of detergent additives often results in an antagonistic effect on the effectiveness of the added cold flow improvers. In the process, the paraffin dispersion of the middle distillate, set by paraffin dispersants, is impaired, without being able to be reconstituted by increased metering of paraffin dispersant. Often the CFPP measured filterability with cold flow improvers additive oils is significantly reduced in the cold and can be compensated only by greatly increased dosage of the flow improver.

Particularly problematic in this case are, in particular, those detergent additives which are derived from higher polyamines and those which are, for example, conditional have very high molecular weights by multiple alkylation and / or acylation of these polyamines. Also particularly problematic are those detergent additives whose hydrophobic residue is derived from sterically hindered olefins and / or higher molecular weight and / or polyfunctionalized poly (olefins).

It was therefore an object of the present invention to improve the response of cold flow improvers in middle distillates containing detergent additives. Another object of the invention was to provide a prior art improved detergent additive which does not interfere with the response of cold flow improvers.

Surprisingly, it has now been found that certain oil-soluble compounds acting as nucleators for the paraffin crystallization counteract the impairment of the effectiveness of conventional cold flow improvers by nitrogen-containing detergent additives or cancel this impairment.

The invention thus relates to the use of at least one oil-soluble compound B) acting as nucleator for paraffin crystallization, selected from substantially linear hydrocarbons having at least 20 C atoms, for improving the response of mineral oil flow improvers C), which are different from B), in middle distillates containing at least one ashless nitrogen-containing detergent additive A) which is an oil-soluble, amphiphilic compound comprising at least one alkyl or alkenyl radical attached to a polar group, the alkyl or alkenyl radical being from 10 to 500 carbon atoms. Atoms and the polar group comprises 2 or more nitrogen atoms.

Another object of the invention is a process for improving the response of mineral oil flow improvers C) in middle distillates containing ashless nitrogen-containing detergent additives A), and wherein the ashless nitrogen-containing detergent additives A) are oil-soluble, amphiphilic compounds comprising at least one alkyl or alkenyl group attached to a polar group, wherein the alkyl or alkenyl group is 10 to 500 carbon atoms and the polar group is 2 or more Includes nitrogen atoms,

by adding at least one oil-soluble compound B), which acts as a nucleator for paraffin crystallization, selected from the group consisting of substantially linear hydrocarbons having at least 20 carbon atoms and different from C).

Another object of the invention are additives containing

a) at least one ashless, nitrogen-containing detergent additive A), which is an oil-soluble, amphiphilic compound comprising at least one alkyl or alkenyl radical attached to a polar group, wherein the

Alkyl or alkenyl radical comprises 10 to 500 C atoms and the polar group comprises 2 or more nitrogen atoms,

and

b) at least one oil-soluble compound B) acting as nucleator for the paraffin crystallization, selected from essentially linear hydrocarbons having at least 20 C atoms and optionally

c) a mineral oil flow improver C) other than B).

The combination of A) and B) is also referred to below as "inventive additive".

Another object of the invention are middle distillates with a

Sulfur content of less than 100 ppm and a 90% distillation point of below 360 ⁰ C, containing a) at least one ashless, nitrogen-containing detergent additive A), which is an oil-soluble, amphiphilic compound comprising at least one alkyl or alkenyl radical bonded to a polar group, wherein the alkyl or alkenyl radical has 10 to 500 carbon atoms and the polar group comprises 2 or more nitrogen atoms,

b) at least one oil-soluble, acting as Nucleator for the paraffin crystallization compound B) selected from substantially linear hydrocarbons having at least 20 C-atoms, and

c) at least one mineral oil flow improver C) other than B).

Under the improvement of the response of cold flow improvers C) is understood according to the invention that at least one by

Cold flow improver C) adjusted or adjustable and by the addition of a detergent additive A) impaired cold property of middle distillates by addition of acting as a nucleating agent for the paraffin crystallization compound B) is improved. Specifically, by adding the nucleating agent B), the cold property set or adjustable without the presence of the detergent additive A) by the cold flow improver C) is achieved. Cold properties are understood here individually or in combination as the pour point, the cold filterability (CoId filter plugging point), the low-temperature flow capability and the paraffin dispersion of middle distillates.

Particularly affected is the response of flow improvers in middle distillates containing more than 10 ppm of a nitrogen-containing detergent additive A) _1, especially more than 20 ppm and especially more than 40 ppm, such as 50 to 2000 ppm of nitrogen-containing detergent additive A).

The additives according to the invention preferably contain from 0.01 to 10 parts by weight, based on one part by weight of the nitrogen-containing detergent additive A), and in particular from 0.05 to 5 parts by weight, for example from 0.1 to 3 parts by weight of the oil-soluble compound B) acting as nucleator for paraffin crystallization.

Ashless means that the additives in question essentially consist only of elements which form gaseous reaction products during combustion. Preferably, the additives consist essentially only of the elements carbon, hydrogen, oxygen and nitrogen. In particular, ashless additives are substantially free of metals and metal salts. Nucleators are understood to be compounds which initiate the crystallization of paraffins on cooling a paraffin-containing oil. They thus shift the beginning of the paraffin crystallization of the oil additized with them, which can be determined, for example, by measuring the cloud point or the Wax Appearance Temperature (WAT), to higher temperatures. These are compounds that are soluble in the oil above the cloud point and begin to crystallize just above the temperature of the paraffin saturation and then serve as seed for the crystallization of the paraffins. Thus, they prevent over-saturation of the oil with paraffins and lead to crystallization near the saturation concentration. This leads to the formation of a multiplicity of equally small paraffin crystals. In the presence of a nucleator, paraffin crystallization thus begins at a higher temperature than in non-additized oil. This can be determined, for example, by measuring the WAT by means of differential scanning calorimetry (DSC) with a slow cooling of the oil at, for example, -2 K / min.

Preferably, middle distillates 10 to 10,000 ppm and in particular 50 to 3,000 ppm of the nitrogen-containing detergent additives A) are added.

Preferably, the alkyl or alkenyl group imparts oil-solubility to the detergent additives.

Particularly problematic are those detergent additives whose alkyl radical 15 to 500 carbon atoms and in particular 20 to 350 carbon atoms such as 50 bis Has 200 C atoms. This alkyl radical can be linear or branched, in particular it is branched. In a preferred embodiment, the alkyl radical is derived from oligomers of lower olefins having 3 to 6 C atoms such as propene, butene, pentene or hexene and mixtures thereof. Preferred isomers of these olefins are isobutene, 2-butene, 1-butene, 2-methyl-2-butene, 2,3-dimethyl-2-butene, 1-pentene, 2-pentene and iso-pentene and mixtures thereof. Particular preference is given to propene, isobutene, 2-butene, 2-methyl-2-butene, 2,3-dimethyl-2-butene and mixtures thereof. Particular preference is given to olefin mixtures containing more than 70 mol%, especially more than 80 mol%, for example more than 90 mol% or more than 95 mol% of 2-methyl-2-butene, 2,3-dimethyl 2-butene and / or isobutene. Particularly suitable for the preparation of such detergent additives are highly reactive low molecular weight polyolefins having a proportion of terminal double bonds of at least 75%, especially at least 85% and in particular at least 90% such as at least 95%. Particularly preferred low molecular weight polyolefins are poly (isobutylene), poly (2-butene), poly (2-methyl-2-butene), poly (2,3-dimethyl-2-butene), poly (ethylene-co-isobutylene) and atactic poly (propylene). The molecular weight of particularly preferred polyolefins is between 500 and 3000 g / mol. Such oligomers of lower olefins are accessible, for example, by polymerization using Lewis acids such as BF ₃ and AICI ₃ , by means of Ziegler catalysts and in particular by means of metallocene catalysts.

The polar component of the detergent additives which are particularly problematic for the response of known cold additives is derived from polyamines having 2 to 20 N atoms. Such polyamines correspond for example to the formula

(R ⁹ ) ₂ N- [AN (R ⁹ )] _q - (R ⁹ )

wherein each R ^{9 is} independently hydrogen, an alkyl or hydroxyalkyl radical having up to 24 carbon atoms, a polyoxyalkylene radical - (AO) _r or polyiminoalkylene radical - [AN (R ⁹ )] _S - (R ⁹ ) but wherein at least R ^{9 is} hydrogen, q is an integer from 1 to 19, A is an alkylene radical having 1 to 6 C atoms, r and s are independently from 1 to 50. Usually these are mixtures of polyamines and in particular mixtures of poly (ethylene amines) and / or poly (propyleneamines). Examples which may be mentioned: ethylenediamine, 1, 2-propylenediamine, dimethylaminopropylamine, diethylenetriamine (DETA), dipropylenetriamine, triethylenetetramine (TETA), tripropylenetetramine, tetraethylenepentamine (TEPA), tetrapropylenepentamine, pentaethylenehexamine (PEHA) pentapropylenehexamine and heavy polyamines. Heavy polyamines are generally understood as meaning mixtures of polyalkylenepolyamines which, in addition to small amounts of TEPA and PEHA, mainly contain oligomers having 7 or more nitrogen atoms, of which two or more are in the form of primary amino groups. These polyamines often also contain branched structural elements via tertiary amino groups.

Other suitable amines include those which comprise cyclic structural units derived from piperazine. The piperazine units may preferably carry hydrogen at one or both nitrogen atoms, an alkyl or hydroxyalkyl radical having up to 24 carbon atoms or a polyiminoalkylene radical - [AN (R ⁹ )] _S - (R ⁹ ) where A, R ⁹ and s have the meanings given above.

Other suitable amines include alicyclic diamines such as 1,4-di (aminomethyl) cyclohexane and heterocyclic nitrogen compounds such as imidazolines and N-aminoalkylpiperazines such as N- (2-aminoethyl) piperazine.

Also, detergent additives whose polar portion is derived from hydroxyl-bearing polyamines, heterocycle-substituted polyamines, and aromatic polyamines are problematic. Examples include: N- (2-hydroxyethyl) ethylenediamine,

N, N ¹ -bis (2-hydroxyethyl) ethylenediamine, N- (3-hydroxybutyl) tetra (methylene) diamine,

N-2-aminoethylpiperazine, N-2 and N-3-aminopropylmorpholine, N-3- (dimethylamino) propylpiperazine, 2-heptyl-3- (2-aminopropyl) imidazoline,

1, 4-bis (2-aminoethyl) piperazine, 1- (2-hydroxyethyl) piperazine, various

Isomers of phenylenediamine and naphthalenediamine and mixtures of these amines. Detergent additives based on heavy polyamines, in which R ^{9 is} hydrogen in the above formula and q has values of at least 3, in particular at least 4, such as 5, 6 or 7, are particularly critical for the cold additization of middle distillates. For mixtures of various polyamines, a proportion of more than 10 wt .-%, in particular more than 20 wt .-% and especially of more than 50 wt .-% of amines having q-values of 4 or higher and especially with q Values of 5 or higher and in particular with q values of 6 or higher on the total amount of amines used have proven particularly critical.

The oil-soluble alkyl moiety and the polar head group of the detergent additives may be linked together either directly via a C-N or through an ester, amide or imide bond. Accordingly, preferred detergent additives are alkylpolyamines, Mannich reaction products, hydrocarbyl-substituted succinic acid amides and imides, and mixtures of these classes of substances. The detergent additives linked via C-N bonds are preferably alkylpoly (amines) which are obtainable, for example, by reacting polyisobutylenes with polyamines, for example by hydroformylation and subsequent reductive amination with the abovementioned polyamines. In this case, one or more alkyl radicals may be bound to the polyamine. Detergent additives based on higher polyamines having more than 4 N atoms, for example those having 5, 6 or 7 N atoms, are particularly critical for the cold addition.

Detergent additives containing amide or imide bonds are obtainable, for example, by reacting alkenylsuccinic anhydrides with polyamines. Alkenylsuccinic anhydride and polyamine are preferably reacted in a molar ratio of about 1: 0.5 to about 1: 1. The preparation of the underlying Alkenylbernsteinsäureanhydride is usually carried out by addition of ethylenically unsaturated polyolefins or chlorinated polyolefins to ethylenically unsaturated dicarboxylic acids. For example, alkenyl succinic anhydrides can be prepared by reaction of chlorinated polyolefins with maleic anhydride. Alternatively, the preparation can also be achieved by thermal addition of polyolefins to maleic anhydride in an "ene reaction." Highly reactive olefins having a high content of, for example, more than 75% and especially more than 85 mol%, based on the total number of polyolefin molecules, are present The terminal double bonds can be both vinylidene double bonds [-CH ₂ -C (= CH ₂ ) -CH ₃ ] and vinyl double bonds [-CH = C (CH ₃ ) ₂ ]. act.

For the preparation of alkenylsuccinic anhydrides, the molar ratio of the two reactants in the reaction between maleic anhydride and polyolefin can vary within wide limits. Preferably, it may be between 10: 1 and 1: 5, with molar ratios of 6: 1 to 1: 1 being particularly preferred. Maleic anhydride is preferably used in stoichiometric excess, for example 1.1 to 3 mol of maleic anhydride per mole of polyolefin. Excess maleic anhydride can be removed from the reaction by, for example, distillation. Since the adducts which are primarily formed by the ene reaction, in turn, contain an olefinic double bond, suitable addition of unsaturated dicarboxylic acids to form so-called bis-maleinates is possible with a suitable reaction procedure. The accessible reaction products have, based on the reacted with unsaturated carboxylic acids fractions of the poly (olefins) on average a Maleinierungsgrad of more than 1, preferably about 1, 01 to 2.0 and in particular 1, 1 to 1, 8 dicarboxylic acid per alkyl radical. Reaction with the abovementioned amines results in products with markedly increased effectiveness as detergent additives. On the other hand, as the degree of maleation increases, so does the impairment of the efficacy of cold flow improvers.

The reaction of alkenyl succinic anhydrides with polyamines results in products having one or more amide and / or imide bonds per polyamine and depending on the Maleinierungsgrad one or two polyamines per alkyl radical can carry. For the reaction of 1, 0 to 1, 7 and in particular 1, 1 to 1, 5 mol alkenylsuccinic anhydride per mol of polyamine are preferably used, so that free primary amino groups remain in the product. In another preferred embodiment, alkenyl succinic anhydride and polyamine are reacted equimolarly. In the reaction of polyamines with alkenyl succinic anhydrides with a high degree of acylation of 1, 1 or more anhydride groups per alkyl radical such as 1, 3 or more anhydride per alkyl radical also arise polymers that are particularly problematic for the response of cold additives.

Typical and particularly preferred acylated nitrogen compounds are obtained by reacting poly (isobutylene), poly (2-butenyl), poly (2-methyl-2-butenyl) -, poly (2,3-dimethyl-2-butenyl) - or Poly (propenyl) succinic anhydrides having an average of about 1, 2 to 1, 5 anhydride groups per alkyl radical whose alkylene radicals carry between 50 and 400 carbon atoms, with a mixture of poly (ethylene amines) having about 3 to 7 nitrogen atoms and about 1 to 6 ethylene units available.

Also, oil-soluble Mannich reaction products based on polyolefin-substituted phenols and polyamines impair the effectiveness of conventional

Cold flow improvers. Mannich bases of this kind are prepared by known processes, for example by alkylating phenol and / or salicylic acid with the polyolefins described above, such as, for example, poly (isobutylene), poly (2-butene), poly (2-methyl-2-butene), poly ( 2,3-dimethyl-2-butene) or atactic poly (propylene) and subsequent condensation of the alkylphenol with aldehydes having 1 to 6 carbon atoms such as formaldehyde or its reactive equivalents such as formalin or paraformaldehyde and the above-described polyamines such as TEPA, PEHA or heavy polyamines produced.

The average molecular weight determined by means of vapor pressure osmometry is particularly more efficient, but at the same time also for the cold additization of middle distillates of particularly critical detergent additives is above 800 g / mol and in particular above 2,000 g / mol such as above 3,000 g / mol. The average molecular weight of the above-described detergent additives can also be increased via crosslinking reagents and adapted to the intended use. Suitable crosslinking reagents are, for example, dialdehydes such as glutaric dialdehyde, bisepoxides derived, for example, from bisphenol A, dicarboxylic acids and their reactive derivatives such as maleic anhydride and alkenylsuccinic anhydrides, and higher polybasic carboxylic acids and their derivatives such as trimellitic acid, trimellitic anhydride and pyromellitic dianhydride. Preferred, acting as Nucleator for paraffin crystallization

Hydrocarbons containing at least 24 C atoms linear alkyl chain are n-paraffins, monomeric α-olefins and paraffin waxes.

Preferred hydrocarbons B) acting as nucleator for paraffin crystallization may be of natural or synthetic origin. These hydrocarbons are preferably linear or have at least longer linear structural units. Suitable hydrocarbons are, for example, alkanes and alkenes. They preferably contain hydrocarbon chains having 20 to 100 carbon atoms, particularly preferably having 20 to 60 carbon atoms, in particular having 22 to 50 carbon atoms, for example having 24 to 40 carbon atoms. At least 35% by weight, particularly preferably at least 50% by weight and in particular at least 80% by weight, for example more than 90% by weight, of the alkanes or alkenes are preferably linear. In a specific embodiment, the hydrocarbon chains consist of linear alkanes or alkenes. Preferred alkanes thus preferably correspond to the sum formula of C20H42 to C1 ₀₀ H20. ₂ particularly preferably C20H42 to C ₆ oHi22, in particular C22H46 to C50 H102 such as, for example, C2 ₄ H ₅₀ to The molecular weights of preferred hydrocarbons B) are between about 280 and 2,800 g / mol, more preferably between about 310 and 700 g / mol, for example between about 336 and 560 g / mol. Although individual hydrocarbons can be used, mixtures of various hydrocarbons in the above-mentioned chain length range have proven particularly useful. Preferred alkanes of natural origin can be obtained, for example, from fossil or mineral raw materials. In a first preferred embodiment, recoverable paraffins are used from different fractions of crude distillation. For example, heavy gas oil fractions containing at least 10 wt .-%, preferably 20 to 90 wt .-%, such as 50 to 70 wt .-% of corresponding alkanes or alkenes are used. Such gas oil fractions preferably have boiling ranges of about 300 to 550 ⁰ C such as 330 to 500 ° C. In a further preferred embodiment, paraffins are used in the dewaxing of gas oils or lubricating oils. Thus, for example, "slackwax" designated paraffins are very suitable, which usually contain at least 40 wt .-%, preferably at least 60 wt .-% of n-alkanes having at least 20 carbon atoms or species with correspondingly long linear structural units.

In addition to macrocrystalline paraffins, which are also referred to as hard paraffins and consist mainly of n-alkanes, especially microcrystalline paraffins are also suitable. These products, also known as microwaxes, are characterized by a higher proportion of iso-paraffins, the more easily handled physical properties compared to the macrocrystalline

Paraffin causes. In the case of microcrystalline waxes, preference is given to those which contain higher proportions of preferably at least 10% by weight and in particular at least 20% by weight of longer-chain paraffin structures having at least 20 carbon atoms, thus having partially crystalline properties and are capable of initiating paraffin crystallization. The melting range of preferred microcrystalline paraffins is between 40 ⁰ C and 90 ^C and in particular between 45 and 80 ⁰ C such as between 50 and 65 ⁰ C. A possible residual content of waxes to oil is in principle not a problem, but must be in determining the dosing of the Additive to be considered. In a further preferred embodiment, synthetic paraffins, as obtained, for example, by means of the Fischer-Tropsch synthesis, are used as nucleator B). FT paraffins consist mainly of normal paraffins. More than 90% are usually n-alkanes, the rest are iso-alkanes. The solidification point of preferred FT waxes is between about 35 ⁰ C and about 90 ⁰ C and in particular between 40 and 70 ⁰ C. Also isomerized FT waxes are suitable according to the invention, but their reduced crystallinity must be taken into account in determining the metering.

In a further preferred embodiment, hydrocarbons B) acting as nucleator for paraffin crystallization are used. These are preferably of synthetic origin and can be prepared, for example, by oligomerization of ethylene. Α-olefins having 20 or more carbon atoms, such as, for example, C 1 -α-olefin, have proven particularly suitable,

C ₂₄ -α-olefin, C ₂₆ -α-olefin or C ₂ β-α-olefin. Advantageously, α-olefins are used in mixtures of different chain lengths. Thus, in particular mixtures of C ₂ o-2 have ₄ -α-olefins, C _26/28 -α-olefins and C ₂₄ - to be particularly useful ₃₀ + and C ₃₆ + ₂₈ -a-olefin and chain-sections in the area C. In this case, technical grades are preferably used which have a content of α-olefins having at least 20 carbon atoms of preferably at least 30 wt .-%, preferably at least 50 wt .-% and in particular at least 70 wt .-% such as at least 90 wt. -% to have. By α-olefins are meant linear olefins with terminal double bond. Hydrogenation in synthetic n-paraffins converted α-olefins are also suitable as nucleators.

The quantitative ratio between detergent additive A) and nucleators B) in the additized oil can vary within wide limits. It has proven particularly useful to use from 0.01 to 10 parts by weight, in particular from 0.05 to 5 parts by weight, for example from 0.1 to 3 parts by weight of nucleator per part by weight of detergent additive, in each case based on the active ingredient.

As flow improver C), which are used in the middle distillates according to the invention, in particular one or more of the following

Substance classes III to VII into consideration, preference being given to using ethylene copolymers (constituent III) or mixtures thereof with one or more of constituents IV to VII. Mixtures have proven particularly useful here of ethylene copolymers (component III) and alkylphenol-aldehyde resins (component V) and of ethylene copolymers (component III) and comb polymers (component VI). Mixtures of ethylene copolymers (constituent III) with constituents IV and V or constituents IV and VI have proven particularly suitable for the paraffin dispersion.

Preferred cold flow improvers as constituent III are copolymers of ethylene and olefinically unsaturated compounds. Suitable ethylene copolymers are, in particular, those which contain, in addition to ethylene, from 8 to 21 mol%, in particular from 10 to 18 mol%, of olefinically unsaturated comonomer compounds.

The olefinically unsaturated compounds are preferably vinyl esters, acrylic esters, methacrylic esters, alkyl vinyl ethers and / or alkenes, it being possible for the abovementioned compounds to be substituted by hydroxyl groups. One or more comonomers may be included in the polymer.

The vinyl esters are preferably those of the formula 1

CH ₂ = CH-OCOR ¹ (1)

wherein R ^{1 is} C ₁ to C ₃₀ alkyl, preferably C ₄ to C ₆ alkyl, especially C ₆ - to C ₂ alkyl. In a further embodiment, said alkyl groups may be substituted with one or more hydroxyl groups.

In a further preferred embodiment, R ^{1 is} a branched alkyl radical or a neoalkyl radical having 7 to 11 carbon atoms, in particular having 8, 9 or 10 carbon atoms. Particularly preferred vinyl esters are derived from secondary and especially tertiary carboxylic acids whose branching is in the alpha position to the carbonyl group. Suitable vinyl esters include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl hexanoate, vinyl heptanoate, vinyl octanoate, vinyl pivalate, vinyl 2-ethylhexanoate, vinyl laurate, vinyl stearate and versatic acid esters such as vinyl neononanoate, vinyl neodecanoate, vinyl neoundecanoate.

In a further preferred embodiment, these ethylene copolymers contain vinyl acetate and at least one further vinyl ester of the formula 1 in which R ^{1 is} C ₄ to C ₃₀ -alkyl, preferably C ₄ to C- ₆ alkyl, especially C ₆ - to C ₁₂ alkyl.

The acrylic esters are preferably those of the formula 2

CH ₂ = CR ² -COOR ³ (2)

wherein R ^{2 is} hydrogen or methyl and R ^{3 is} Cr to C ₃₀ -alkyl, preferably C ₄ - to C ₆ -alkyl, especially C ₆ - to C ₁₂ -alkyl. Suitable acrylic esters include, for. Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n- and iso-butyl (meth) acrylate, hexyl, octyl, 2-ethylhexyl, decyl, dodecyl, tetradecyl , Hexadecyl, octadecyl (meth) acrylate and mixtures of these comonomers. In a further embodiment, said alkyl groups may be substituted with one or more hydroxyl groups. An example of such an acrylic ester is hydroxyethyl methacrylate.

The alkyl vinyl ethers are preferably compounds of the formula 3

CH ₂ = CH-OR ⁴ (3)

wherein R ⁴ d- to C ₃₀ alkyl, preferably C ₄ - to C | _6- alkyl, especially C ₆ - bis

Ci2-alkyl. Examples which may be mentioned are methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether. In a further embodiment, said alkyl groups may be substituted with one or more hydroxyl groups.

The alkenes are preferably simple unsaturated hydrocarbons having 3 to 30 carbon atoms, especially 4 to 16 carbon atoms and especially 5 to 12 carbon atoms. Suitable alkenes include propene, butene, isobutylene, pentene, hexene, 4-methylpentene, octene, Diisobutylene and norbornene and its derivatives such as methylnorbomene and vinylnorbomene. In a further embodiment, said alkyl groups may be substituted with one or more hydroxyl groups.

Particular preference is given to terpolymers which, apart from ethylene, have from 3.5 to 20 mol%, in particular from 8 to 15 mol% of vinyl acetate and from 0.1 to 12 mol%, in particular from 0.2 to 5 mol%, of at least one longer-chain and preferably branched one Vinyl esters such as vinyl 2-ethylhexanoate, vinyl neononanoate or vinyl neodecanoate, wherein the total comonomer content of the terpolymers is preferably between 8 and 21 mol%, in particular between 12 and 18 mol%. Until Ci ₂ carboxylic acids 0.5 to 10 mol% olefins, such as propene, butene, isobutylene, hexene, 4-methylpentene, octene, diisobutylene - Further particularly preferred copolymers contain, in addition to ethylene and from 8 to 18 mol% of C ₂ Vinylestern and / or norbomene.

Preferably, these ethylene-co- and terpolymers have melt viscosities at 14O ⁰ C from 20 to 10,000 mPas, in particular from 30 to 5,000 mPas, especially from 50 to 2,000 mPas. The means of ¹ H-NMR spectroscopy, certain degrees of branching are preferably between 1 and 9 CH ₃ / CH ₂ groups IOO, especially between 2 and 6 CH ₃ / IOO CH ₂ groups that do not stem from the comonomers.

Preference is given to using mixtures of two or more of the abovementioned ethylene copolymers. Particularly preferably, the polymers underlying the mixtures differ in at least one

Characteristic. For example, they may contain different comonomers, have different comonomer contents, molecular weights and / or degrees of branching.

The mixing ratio between the additives according to the invention and ethylene copolymers as constituent III can vary within wide limits depending on the application, with the ethylene copolymers III often representing the greater proportion. Preferably, such additive and oil mixtures contain 0.1 to 25, preferably 0.5 to 10 parts by weight of ethylene copolymers per part by weight of the additive combination according to the invention.

Other cold flow improvers which are suitable are oil-soluble polar nitrogen compounds (constituent IV). These are preferably

Reaction products of fatty amines with compounds containing an acyl group. The preferred amines are compounds of the formula NR ⁶ R ⁷ R ⁸ , in which R ⁶ , R ⁷ and R ^{8 may be} identical or different, and at least one of these groups is C ₈ -C ₃₆ -alkyl, C ₆ - C ₃₆ -CyClOaIkVl, C ₈ -C ₃₆ alkenyl, in particular C ₂ -C ₂₄ alkyl, C ₂ -C ₂₄ alkenyl or cyclohexyl, and the other groups are either hydrogen, C 1 -C ₃₆ -alkyl, C ₂ - C- ₃₆ alkenyl, cyclohexyl, or a group of the formulas - (AO) _x -E or - (CH ₂ ) _n -NYZ, where A is an ethyl or propyl group, x is a number from 1 to 50, E = H, = 2, 3 or 4 -C ₃ -alkyl, C ₅ -C ₁₂ cycloalkyl or C ₆ -C ₃₀ -aryl, and n, and Y and Z are independently H, -C ₃ O-alkyl or - (AO) _x . Also polyamines of the formula - [N- (CH ₂ ) _n ] _m -NR ⁶ R ⁷ , in which m is a number between 1 and 20 and n, R ⁶ and R ^{7 have} the meanings given above, are suitable as fatty amines , The alkyl and alkenyl radicals can be linear or branched and contain up to two double bonds. They are preferably linear and substantially saturated, ie they have iodine numbers of less than 75 gl ₂ / g, preferably less than 60 gl ₂ / g and in particular between 1 and 10 gl ₂ / g. Particular preference is given to secondary fatty amines in which two of the groups R ⁶ , R ⁷ and R ^{8 are} C ₈ -C ₃₆ -alkyl, C ₆ -C ₃₆ -cycloalkyl, C ₈ -C ₃₆ -alkynyl, in particular C- C ₂ -C ₂₄ alkyl, C ₁₂ -C ₂₄ alkenyl or cyclohexyl. Suitable fatty amines are, for example, octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, eicosylamine, behenylamine, didecylamine, didodecylamine, ditetradecylamine, dihexadecylamine, dioctadecylamine, dieicosylamine, dibehenylamine and mixtures thereof. Specifically, the amines contain chain cuts based on natural raw materials such as coco fatty amine, tallow fatty amine, hydrogenated tallow fatty amine, dicocosfettamine, ditallow fatty amine and di (hydrogenated tallow fatty amine). Particularly preferred amine derivatives are amine salts, imides and / or amides such as amide Ammonium salts of secondary fatty amines, in particular of dicocosfettamine, ditallow fatty amine and distearylamine.

By acyl group is meant here a functional group of the following formula:

> C = O

Suitable carbonyl compounds for the reaction with amines are both monomeric and polymeric compounds having one or more carboxyl groups. In the case of the monomeric carbonyl compounds, preference is given to those having 2, 3 or 4 carbonyl groups. They can also contain heteroatoms such as oxygen, sulfur and nitrogen. Examples of suitable carboxylic acids are maleic, fumaric, crotonic, itaconic, succinic, C 1 -C ₄ -alkenylsuccinic, adipic, glutaric, sebacic and malonic acids and also benzoic, phthalic, trimellitic and pyromellitic acid, nitrilotriacetic acid .

Ethylenediaminetetraacetic acid and its reactive derivatives such as esters, anhydrides and acid halides. Copolymers of ethylenically unsaturated acids, such as, for example, acrylic acid, methacrylic acid, maleic acid, fumaric acid and itaconic acid, have proven to be particularly suitable as polymeric carbonyl compounds; particularly preferred are copolymers of

Maleic anhydride. Suitable comonomers are those which impart oil solubility to the copolymer. Oil-soluble means here that the copolymer dissolves without residue in the middle distillate to be additive after reaction with the fatty amine in practice-relevant metering rates. Suitable comonomers are, for example, olefins, alkyl esters of acrylic acid and

Methacrylic acid, alkyl vinyl esters and alkyl vinyl ethers having 2 to 75, preferably 4 to 40 and in particular 8 to 20 carbon atoms in the alkyl radical. In the case of olefins, the carbon number refers to the alkyl radical attached to the double bond. The molecular weights of the polymeric carbonyl compounds are preferably between 400 and 20,000, more preferably between 500 and 10,000, for example between 1,000 and 5,000. Oil-soluble polar nitrogen compounds which have been 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 have proven particularly suitable (compare US Pat. No. 4,211,534). The same are amides and ammonium salts of

Aminoalkylenpolycarbonsäuren such as nitrilotriacetic acid or ethylenediaminetetraacetic acid with secondary amines as oil-soluble polar nitrogen compounds suitable (see EP 0398101). Other oil-soluble polar nitrogen compounds are copolymers of maleic anhydride with α, β-unsaturated compounds, optionally with primary

Monoalkylamines and / or aliphatic alcohols can be reacted (see, EP-A-O 154 177,

EP-O 777 712), the reaction products of alkenyl spiro-bis-lactones with amines (cf., EP-A-0 413 279 B1) and EP-AO 606 055 A2 reaction products of terpolymers based on α, ß-unsaturated dicarboxylic anhydrides, α, ß-unsaturated compounds and Polyoxyalkylenethem lower unsaturated

Alcohols.

The mixing ratio between the ethylene copolymers of the invention

III and oil-soluble polar nitrogen compounds as ingredient IV may vary depending on the application. Such additive mixtures preferably contain 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, based on the active compounds, of at least one oil-soluble polar nitrogen compound per part by weight of the additive combination according to the invention.

Also suitable as flow improvers are alkylphenol-aldehyde resins as

Component V. These are, in particular, those alkylphenol-aldehyde resins which are derived from alkylphenols having one or two alkyl radicals in ortho and / or para position to the OH group. Particularly preferred as starting materials are alkylphenols which carry at least two hydrogen atoms capable of condensation with aldehydes on the aromatic and in particular monoalkylated phenols. Particularly preferably, the alkyl radical is in the para position to the phenolic OH group. The alkyl radicals (among which are generally understood for the constituent V hydrocarbon radicals as defined below) may be the same or different in the alkylphenol-aldehyde resins usable in the process according to the invention, they may be saturated or unsaturated and preferably have 1-20, especially 4-16, such as 6-12 carbon atoms; it is preferably n-, iso- and tert-butyl, n- and iso-pentyl, n- and iso-hexyl, n- and iso-octyl, n- and iso-nonyl-, n - and iso-decyl, n- and iso-dodecyl, tetradecyl, hexadecyl, octadecyl, tripropenyl, tetrapropenyl, poly (propenyl) - and poly (isobutenyl) radicals. In a preferred embodiment, mixtures of alkylphenols having different alkyl radicals are used for the preparation of the alkylphenol resins. For example, resins based on butyphenol on the one hand and octyl, nonyl and / or dodecylphenol in a molar ratio of 1:10 to 10: 1, on the other hand, have proven particularly useful. Suitable alkylphenol resins may also contain or consist of structural units of other phenol analogs such as salicylic acid, hydroxybenzoic acid and derivatives thereof such as esters, amides and salts.

Suitable aldehydes for the alkylphenol-aldehyde resins are those having 1 to 12 carbon atoms and preferably those having 1 to 4 carbon atoms such as formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, 2-ethylhexanal, benzaldehyde, glyoxalic acid and their reactive equivalents such as paraformaldehyde and trioxane. Particularly preferred is formaldehyde in the form of paraformaldehyde and especially formalin.

The molecular weight of the alkylphenol-aldehyde resins measured by gel permeation chromatography against poly (styrene) standards in THF is preferably 500-25,000 g / mol, more preferably 800-10,000 g / mol, and especially

1,000-5,000 g / mol such as 1,500-3,000 g / mol. The prerequisite here is that the alkylphenol-aldehyde resins, at least in application-relevant concentrations of 0.001 to 1 wt .-% are oil-soluble.

In a preferred embodiment of the invention, these are alkylphenol-formaldehyde resins, the oligo- or polymers having a repetitive structural unit of the formula

wherein R ^{11 is} C _r C ₂ o-alkyl or alkenyl, OR ¹⁰ or OC (O) -R ¹⁰ , R ^{10 is} C _r C ₂ oo-alkyl or alkenyl and n is a number from 2 to 100, contain. R ¹⁰ preferably represents Ci-C ₂ o alkyl or alkenyl and especially C ₄ -C ₆ alkyl or alkenyl such as for C ₆ -C ₂ alkyl or alkenyl. Particularly preferably, R ¹¹ -C ₂ o alkyl or alkenyl, and in particular C ₄ -C ₁₆ - alkyl or alkenyl such as for C ₆ -C ₂ alkyl or alkenyl. Preferably, n is a number from 2 to 50 and especially a number from 3 to 25, such as a number from 5 to 15.

These alkylphenol-aldehyde resins are accessible by known methods, for. B. by condensation of the corresponding alkylphenols with formaldehyde, d. H. with 0.5 to 1, 5 mol, preferably 0.8 to 1, 2 moles of formaldehyde per mole of alkylphenol. The condensation can be carried out solvent-free, but preferably it takes place in

Presence of a non or only partially water-miscible inert organic solvent such as mineral oils, alcohols, ethers and the like. Particularly preferred are solvents which can form azeotropes with water. As such solvents are in particular aromatics such as toluene, xylene Diethylbenzol and higher-boiling commercial solvent mixtures such as Shellsol ^® AB, and solvent

Naphtha used. Also, fatty acids and their derivatives such as esters with lower alcohols having 1 to 5 carbon atoms such as ethanol and especially methanol are suitable as solvents. The condensation is preferably carried out between 70 and 200 ^° C., for example between 90 and 160 ^° C. It is usually catalysed by 0.05 to 5% by weight of bases or preferably by 0.05 to 5% by weight of acids. As acidic catalysts are in addition to carboxylic acids such as acetic acid and oxalic acid in particular strong mineral acids such as hydrochloric acid, phosphoric acid and sulfuric acid and sulfonic acids commonly used catalysts. Particularly suitable catalysts are sulfonic acids which contain at least one sulfonic acid group and at least one saturated or unsaturated, linear, branched and / or cyclic hydrocarbon radical having 1 to 40 C atoms and preferably having 3 to 24 C atoms. Particular preference is given to aromatic sulfonic acids, especially alkylaromatic monosulfonic acids having one or more C ₁ -C ₂₈ -alkyl radicals and, in particular, those having C ₃ -C ₂₂ -alkyl radicals. Suitable examples are methanesulfonic acid, butanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, xylenesulfonic acid, 2-mesitylenesulfonic acid, 4-ethylbenzenesulfonic acid, isopropylbenzenesulfonic acid, 4-butylbenzenesulfonic acid, 4-octylbenzenesulfonic acid; Dodecylbenzenesulfonic acid, didodecylbenzenesulfonic acid, naphthalenesulfonic acid. Mixtures of these sulfonic acids are suitable. Usually, these remain after completion of the reaction as such or in neutralized form in the product. For neutralization, amines and / or aromatic bases are preferably used, since they can remain in the product; Metal ions containing and thus ash-forming salts are usually separated.

Likewise suitable as flow improvers comb polymers (component VI), for example, by the formula

HH

D M N

to be discribed. Mean in it

AR ¹ , COOR ¹ , OCOR ¹ , FT-COOR ¹ , OR ¹ ; DH ₁ CH ₃ , A or R "; EH ₁ A; GH, R ", FT-COOR ¹ , an aryl radical or a heterocyclic radical;

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

N H, R ", COOR", OCOR, an aryl radical;

R ^{1 is} a hydrocarbon chain having 8 to 20, preferably 10 to 18 carbon atoms;

R "is a hydrocarbon chain of 1 to 10 carbon atoms, m is a number between 0.4 and 1.0, and n is a number between 0 and 0.6.

Suitable comb polymers are, for example, copolymers of ethylenically unsaturated dicarboxylic acids such as maleic or fumaric acid with other ethylenically unsaturated monomers such as olefins or vinyl esters such as vinyl acetate. Particularly suitable olefins are α-olefins having 10 to 20 and especially 12 to 18 carbon atoms such as 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene and mixtures thereof. Even longer-chain olefins based on oligomerized C ₂ -C ₆ -olefins such as poly (isobutylene) with a high proportion of terminal double bonds are suitable as comonomers. Usually, these copolymers are at least 50% esterified with alcohols having 10 to 20 and especially 12 to 18 carbon atoms. Suitable alcohols include n-decan-1-ol, n-dodecan-1-ol, n-tetradecan-1-ol, n-hexadecan-1-ol, n-octadecan-1-ol and mixtures thereof. Particular preference is given to mixtures of n-tetradecan-1-ol and n-hexadecan-1-ol. Also suitable as comb polymers are poly (alkyl acrylates), poly (alkyl methacrylates) and poly (alkyl vinyl ethers) derived from alcohols containing 10 to 20 and especially 12 to 18 carbon atoms, and poly (vinyl esters) derived from fatty acids containing 10 to Derive 20 and especially 12 to 18 carbon atoms.

Also suitable as flow improvers are oil-soluble

Polyoxyalkylene compounds (constituent VII) such as, for example, esters, ethers and ether / esters of polyols which carry at least one alkyl radical having 12 to 30 C atoms. In a preferred embodiment, the oil-soluble polyoxyalkylene compounds have at least 2, such as, for example, 3, 4 or 5 aliphatic hydrocarbon radicals. Preferably, these radicals are independent each other 16 to 26 carbon atoms such as 17 to 24 carbon atoms. Preferably, these radicals of the oil-soluble polyoxyalkylene compounds are linear. Further preferably, they are largely saturated, in particular, these are alkyl radicals. Esters are especially preferred.

Particularly suitable polyols according to the invention are polyethylene glycols, polypropylene glycols, polybutylene glycols and their copolymers having a molecular weight of about 100 to about 5,000 g / mol, preferably 200 to 2,000 g / mol. In a particularly preferred embodiment, the oil-soluble polyoxyalkylene compounds are derived from polyols having 3 or more OH groups, preferably from polyols having 3 to about 50 OH groups such as 4 to 10 OH groups, in particular neopentyl glycol, glycerol, trimethylolethane, trimethylolpropane , Sorbitan, pentaerythritol, as well as the resulting from condensation oligomers having 2 to 10 monomer units such as. As polyglycerol. Even higher polyols such as sorbitol, sucrose, glucose, fructose and their oligomers such as cyclodextrin are suitable as polyols, provided that their esterified or etherified alkoxylates are oil-soluble at least in application-relevant amounts. Preferred polyoxyalkylene compounds thus have a branched polyoxyalkylene nucleus to which are attached multiple alkyl-solubilizing alkyl radicals.

The polyols are generally reacted with from 3 to 70 mol of alkylene oxide, preferably from 4 to 50, in particular from 5 to 20, mol of alkylene oxide per hydroxyl group of the polyol. Preferred alkylene oxides are ethylene oxide, propylene oxide and / or butylene oxide. The alkoxylation is carried out by known methods.

The fatty acids which are suitable for the esterification of the alkoxylated polyols preferably have 12 to 30 and in particular 16 to 26 C atoms. Suitable fatty acids are, for example, lauric, tridecane, myristic, pentadecane, palmitic, margarine, stearic, isostearic, arachinic and behenic, oil and

Erucic acid, palmitoleic, myristoleic, ricinoleic acid, as well as from natural fats and oils derived fatty acid mixtures. Preferred fatty acid mixtures contain more than 50 mol% of fatty acids having at least 20 carbon atoms. Prefers contain less than 50 mol% of the fatty acids used for esterification double bonds, in particular less than 10 mol%; specifically, they are largely saturated. The esterification can also be carried out starting from reactive derivatives of the fatty acids such as esters with lower alcohols (for example methyl or ethyl esters) or anhydrides.

For the purposes of the present invention, the term "iodine number" of the fatty acid or of the fatty alcohol used is understood to be largely saturated by up to 5 g of I per 100 g of fatty acid or fatty alcohol.

For the esterification of the alkoxylated polyols, it is also possible to use mixtures of fatty acids with fat-soluble, polybasic carboxylic acids. Examples of suitable polybasic carboxylic acids are dimer fatty acids, alkenylsuccinic acids and aromatic polycarboxylic acids and derivatives thereof such as anhydrides and Cr to Cs esters. Alkenylsuccinic acid and its derivatives with alkyl radicals having 8 to 200, in particular 10 to 50, carbon atoms are preferred. Examples are dodecenyl, octadecenyl and

Poly (isobutenyl) succinic anhydride. The polybasic carboxylic acids are preferably used here to lower levels of up to 30 mol%, preferably 1 to 20 mol%, in particular 2 to 10 mol%.

Ester and fatty acid are used for the esterification based on the content of hydroxyl groups on the one hand and carboxyl groups on the other hand in a ratio of 1, 5: 1 to 1: 1, 5, preferably in the ratio 1, 1: 1 to 1: 1, 1 and in particular equimolar. The acid number of the esters formed is generally below 15 mg KOH / g, preferably below 10 mg KOH / g, especially below 5 mg KOH / g. The OH number of the esters is preferably below 20 mg KOH / g and especially below 10 mg KOH / g.

In a preferred embodiment, after the alkoxylation of the polyol, the terminal hydroxyl groups are converted, for example, by oxidation or by reaction with dicarboxylic acids into terminal carboxyl groups. By reaction with fatty alcohols with 8 to 50, in particular 12 to 30, especially 16 to 26 C-atoms are also obtained according to the invention Polyoxyalkylenester. Preferred fatty alcohols or fatty alcohol mixtures contain more than 50 mol% of fatty alcohols having at least 20 carbon atoms. Preferably, less than 50 mol% of the fatty alcohols used for the esterification contain double bonds, in particular less than 10 mol%; specifically, they are largely saturated. Also, esters of alkoxylated fatty alcohols with fatty acids which contain the abovementioned proportions of poly (alkylene oxides) and whose fatty alcohol and fatty acid have the abovementioned alkyl chain lengths and degrees of saturation are suitable according to the invention.

Furthermore, the above-described alkoxylated polyols can by

Etherification with fatty alcohols having 8 to 50, especially 12 to 30, especially 16 to 26 carbon atoms in accordance with the invention suitable polyoxyalkylene compounds are converted. The preferred fatty alcohols are linear and largely saturated. Preferably, the etherification takes place completely or at least largely completely. The etherification is carried out by known methods.

Particularly preferred polyoxyalkylene compounds are derived from polyols having 3, 4 and 5 OH groups, which carry about 5 to 10 mol of structural units derived from ethylene oxide per hydroxyl group of the polyol and are largely completely esterified with largely saturated C ₇ -C ₂₄ -fatty acids. Further particularly preferred polyoxyalkylene compounds are polyethylene glycols which have been esterified with largely saturated C ₇ -C ₂₄ -fatty acids and have molecular weights of about 350 to 1,000 g / mol. Examples of particularly suitable polyoxyalkylene compounds are stearic and especially behenic acid esterified polyethylene glycols having molecular weights between 350 and 800 g / mol; Neopentyl glycol 14-ethylene oxide distearate (neopentyl glycol alkoxylated with 14 moles of ethylene oxide and then esterified with 2 moles of stearic acid), and especially neopentyl glycol 14-ethylene oxide dibehenate; Glycerol 20-ethylene oxide tristearate, glycerol 20-ethylene oxide dibehenate, and especially glycerol 20-ethylene oxide tribehenate; Trimethylolpropane-22-ethylene oxide tribehenate; Sorbitan 25-ethylene oxide tristearate, sorbitan 25-ethylene oxide tetrastearate, sorbitan 25-ethylene oxide tribehenate and in particular Sorbitan-25-ethylene oxide tetrabehenat; Pentaerythritol-30-ethylene oxide tribehenate, pentaerythritol-30-ethylene oxide tetrastearate, and especially pentaerythritol-30-ethylene oxide tetrabehenate and pentaerythritol-20-ethylene oxide-10-propylene oxide tetrabehenate.

The mixing ratio between the additives according to the invention and the further constituents V, VI and VII is generally in each case between 1:10 and 10: 1, preferably between 1: 5 and 5: 1.

Only detergent additive A) and Nucleator B) containing inventive additives preferably contain 10 to 90 wt .-% and in particular 20 to 80 wt .-% such as 30 to 70 wt .-% detergent additive A) and 10-90 wt .-% and in particular 20-80% by weight, for example 30-70% by weight of nucleator B). If a further cold flow improver C) is present, the additives preferably contain 15-80% by weight, preferably 20-70% by weight of detergent additive A), 2-40% by weight, preferably 5-25% by weight. Nucleator B) and 15-80% by weight, preferably 20-70% by weight of cold flow improver C).

For ease of handling, the additives according to the invention are preferably used as concentrates which contain from 10 to 95% by weight and preferably from 20 to 80% by weight, for example from 25 to 60% by weight, of solvent. Preferred solvents are higher-boiling aliphatic, aromatic hydrocarbons, alcohols, esters, ethers and mixtures thereof. Such concentrates preferably contain from 0.01 to 10 parts by weight, preferably from 0.05 to 5 parts by weight, for example from 0.01 to 3 parts by weight of the linear hydrocarbons B) acting as nucleator per part by weight of detergent additive A).

The novel nucleators B) improve the response of detergent-containing middle distillates such as kerosene, jet fuel, diesel and heating oil for conventional flow improvers with regard to the reduction of pour point and CFPP value and the improvement of paraffin dispersion. Particularly preferred mineral oil distillates are middle distillates. The middle distillate is especially those mineral oils which are obtained by distillation of crude oil, in the range of about 150 to 450 ⁰ C and in particular in the range of about 170 to 390 ⁰ C boiling, for example kerosene, jet fuel, diesel and fuel oil. Typically, middle distillates contain about 5 to 50 wt .-%, such as about 10 to 35 wt .-% n-paraffins, of which the longer-chain crystallize on cooling and can affect the flowability of the middle distillate. Particularly advantageous are the compositions of the invention in middle aromatics with low aromatic content of less than 21 wt .-%, such as less than 19 wt .-%. Particularly advantageous compositions of the invention are further described in middle distillates with low final boiling point, i.e. in those middle distillates which have 90% distillation points below 360 ⁰ C, in particular 350 ° C. and in special cases below 340 ⁰ C and further in middle distillates, the Siedebreiten between 20 and 90% volume of distillation less than

120 ⁰ C and in particular of less than 110 ⁰ C. By aromatic compounds is meant the sum of mono-, di- and polycyclic aromatic compounds as determinable by HPLC according to DIN EN 12916 (2001 edition). The middle distillates may also contain minor amounts, for example up to 40% by volume, preferably 1 to 20% by volume, especially 2 to 15, for example 3 to 10% by volume of the oils of animal and / or vegetable origin described in more detail below such as fatty acid methyl esters.

The compositions according to the invention are also suitable for improving the cold properties of detergent additives containing fuels based on renewable raw materials (biofuels). By biofuels is meant oils obtained from animal and preferably vegetable material or both, and derivatives thereof, which can be used as fuel and especially as diesel or fuel oil. These are, in particular, triglycerides of fatty acids having 10 to 24 carbon atoms and the fatty acid esters of lower alcohols, such as methanol or ethanol, which are obtainable by transesterification. Examples of suitable biofuels are rapeseed oil, coriander oil, soybean oil, cottonseed oil, sunflower oil, castor oil, olive oil, peanut oil, corn oil, almond oil, palm kernel oil, coconut oil, mustard seed oil, beef tallow, bone oil, fish oils and used edible oils. Other examples include oils derived from wheat, jute, sesame, shea nut, arachis oil and linseed oil. The fatty acid alkyl esters, also referred to as biodiesel, can be derived from these oils by methods known in the art. Rapeseed oil, which is a mixture of glycerol-esterified fatty acids, is preferred because it is available in large quantities, and simply by squeezing out

Rapeseed is available. Furthermore, the also widespread oils of sunflower, palm and soybeans and their mixtures with rapeseed oil are preferred.

Particularly suitable as biofuels are lower alkyl esters of fatty acids. Here are, for example, commercially available mixtures of ethyl, propyl, butyl and especially methyl esters of fatty acids having 14 to 22 carbon atoms, for example of lauric, myristic, palmitic, palmitolic, stearic, oleic, elaidic, petroselinic, ricinoleic, elaeostearic, linoleic, linolenic , Eicosanoic acid, gadoleic acid,

Docosanoic acid or erucic acid into consideration. Preferred esters have an iodine value of from 50 to 150 and in particular from 90 to 125. Mixtures with particularly advantageous properties are those which are principally, i. H. to contain at least 50 wt .-% of methyl esters of fatty acids having 16 to 22 carbon atoms and 1, 2 or 3 double bonds. The preferred lower alkyl esters of fatty acids are the methyl esters of oleic, linoleic, linolenic and erucic acids.

The additives can be used alone or together with other additives, for. With other pour point depressants or dewaxing aids, with other detergents, with antioxidants, cetane number improvers, dehazers, demulsifiers, dispersants, defoamers, colorants, corrosion inhibitors, Lubricity additives, sludge inhibitors, odorants and / or additions to the cloud point.

Examples

Improvement of the cold flowability of middle distillates

To evaluate the effect of the inventive additives on the cold flow properties of middle distillates, detergent additives (A) with different nucleators (B) and further flow improvers (C) with the characteristics given below were used.

The suppression of the negative effect of the detergent additives A) on known cold flow improvers for mineral oils and mineral oil distillates by nucleators B) is described on the one hand by means of the CFIPP test (CoId Filter Plugging Test according to EN 116).

Furthermore, the paraffin dispersion in middle distillates is determined in the short sediment test as follows:

150 ml of the admixed with the additive components shown in the table middle distillates were cooled in 200 ml measuring cylinders in a cold chamber at -2 ° C / hour to -13 ⁰ C and stored for 16 hours at this temperature. Subsequently, the volume and appearance of both the sedimented paraffin phase and the oil phase above are visually determined and assessed. A small amount of sediment and a cloudy oil phase show a good paraffin dispersion.

In addition, immediately after cold storage, the lower 20% by volume is isolated and the cloud point determined according to IP 3015. Only a small deviation of the cloud point of the lower phase (CPKS) from the blank value of the oil shows a good paraffin dispersion. Table 1: Characterization of the test oils:

The test oils used were current middle distillates from European refineries. The CFPP value was determined in accordance with EN 116 and the determination of the cloud point in accordance with ISO 3015. The determination of the aromatic hydrocarbon groups was carried out in accordance with DIN EN 12916 (November 2001 edition)

The following additives were used:

(A) Characterization of the detergent additives used

As Detergent Additives A, various were listed in Table 2

Reaction products of alkenyl succinic anhydrides (ASA) based on highly reactive polyolefins (proportion of terminal double bonds> 90%, degree of maleation about 1, 2 to 1, 3) used with polyamines. Alkenyl succinic anhydride and polyamine were reacted in a molar ratio of 1, 0 to 1, 5 moles of alkenyl succinic anhydride per mole of polyamine (see Table 2). For better meterability, the detergent additives were used as 33% solutions in higher boiling aromatic solvent. However, the dosage rates indicated in Tables 2 to 4 for the detergent additives and nucleators refer to the active ingredients used.

(B) Characterization of the inserted nucleators

B1) Mixture of n-paraffins with chain lengths of C ₂₆ . C ₂ β and C ₃₀ im

Ratio 1: 0.8: 0.6; 10% in higher boiling aromatic solvent.

B2) mixture of α-olefins having major components in the range C _{2 6/2} β; 10% in solvent naphtha

B3) mixture of α-olefins with chain lengths of C ₃ o and longer; 10% in higher boiling aromatic solvent.

(C) Characterization of the further flow improvers used

C1) Terpolymer of ethylene, 13 mol% of vinyl acetate and 2 mol% of vinyl neodecanoate with a measured at 140 ^C C melt viscosity V140 of 95 mPas, 65% in kerosene C2) mixture of equal parts of C1) and a copolymer of ethylene and

13.5 mol% of vinyl acetate with a measured at 140 ⁰ C melt viscosity V140 of 125 mPas, 56% in kerosene.

C3) mixture of 2 parts of reaction product of a copolymer

C14 / C16 α-olefin and maleic anhydride with 2 equivalents of hydrogenated ditallow fatty amine with one part of nonylphenol-formaldehyde resin, 50% in higher boiling aromatic solvent.

C4) reaction product of ethylenediaminetetraacetic acid with 4 equivalents of ditallow fatty amine to the amide ammonium salt, prepared according to EP 0 398 101, 50% higher boiling aromatic solvent.

C5) Mixing equal parts of a reaction product of phthalic anhydride and 2 equivalents of di (hydrogenated tallow fat) amine with a copolymer of fumaric acid ditetradecylester, 50% in higher boiling aromatic solvent.

The determination of the CFPP values in test oil 1 was carried out after adding the oil with 200 ppm C2 and 150 ppm C3.

In the examples of Tables 3 and 4, as detergent additive A1, the reaction product of poly (isobutenyl) -succinic anhydride and pentaethylene-hexamine according to Table 2, Example 4 and as detergent additive A2 the reaction product of poly (isobutenyl) succinic anhydride and pentaethylenehexamine according to Table 2, Example 13 used. Table 2: Effect of nucleators on detergent-induced antagonism in test oil 1

DA = detergent additive; PIB = poly (isobutylene); APP = atactic poly (propylene); P2B = poly (butene) from a mixture of different butene isomers with a proportion of 2-butene of about 80%; TEPA = tetraethylenepentamine; PEHA = pentaethylenehexamine;

PAM = heavy polyamine

Table 3: Cold Flow Improvement in Test Oil 2

Table 4: Cold flow improvement in test oil 3

The experiments show that the impairment of the cold flow properties such as the CFPP value and the paraffin dispersion of middle distillates additized with flow improvers can only be compensated by adding the nucleators according to the invention. By higher dosage of the flow improver alone, this result can not be achieved.

Claims

claims

Use of at least one oil-soluble compound B) acting as nucleator for paraffin crystallization, selected from substantially linear hydrocarbons having at least 20 carbon atoms, for improving the response of mineral oil flow improvers C) in middle distillates comprising at least one ashless nitrogen-containing detergent additive A) which is an oil-soluble, amphiphilic compound comprising at least one alkyl or alkenyl radical attached to a polar group, wherein the alkyl or alkenyl radical

10 to 500 C atoms and the polar group comprises 2 or more nitrogen atoms.

2. Use according to claim 1, wherein, based on one part by weight of the nitrogen-containing detergent additive A), 0.01 to 10 parts by weight of the oil-soluble compound B) acting as nucleator for the paraffin crystallization are used.

3. Use according to claim 1 and / or 2, wherein the middle distillate contains 10 to 10,000 ppm of an ashless nitrogen-containing detergent additive A).

4. Use according to one or more of claims 1 to 3, wherein the ashless nitrogen-containing detergent additive A) has an alkyl radical having 15 to 500 carbon atoms.

5. Use according to claim 4, wherein the alkyl radical is derived from oligomers of lower olefins having 3 to 6 carbon atoms or mixtures thereof.

6. Use according to claim 5, wherein a mixture of oligomers of lower olefins having 3 to 6 carbon atoms is used, containing more than 70 mol% of 2-methyl-2-butene, 2,3-dimethyl-2-butene and / or isobutene.

7. Use according to one or more of claims 1 to 6, wherein the ashless nitrogen-containing detergent additive A) is prepared using highly reactive low molecular weight polyolefins with a proportion of terminal double bonds of at least 75 mol%.

8. Use according to one or more of claims 1 to 7, wherein the ashless nitrogen-containing detergent additive A) comprises a polar portion of polyamines of the formula

(R ⁹⁾ ₂ N- [AN (R ^9)] _q - (R ⁹⁾

wherein each R ^{9 is} independently hydrogen, an alkyl or hydroxyalkyl radical having up to 24 carbon atoms, a polyoxyalkylene radical - (AO) _r - or polyiminoalkylene radical - [AN (R ⁹ )] _S - (R ⁹ ) but wherein at least one R ^{9 is} hydrogen, q is an integer from 1 to 19, A is an alkylene radical having 1 to 6 C atoms, and r and s independently of one another are integers from 1 to 50.

9. Use according to claim 8, wherein R ^{9 is} hydrogen and q assumes values of at least 3.

Use according to one or more of claims 1 to 9, wherein the ashless nitrogen-containing detergent additive A) comprises an oil-soluble alkyl radical and a polar head group, and the oil-soluble alkyl radical and the polar head group via a CN or via an ester, amide or Imide bond are linked together.

11. Use according to one or more of claims 1 to 10, wherein the ashless nitrogen-containing detergent additive A) has a determined by Dampfdruckosmometrie average molecular weight of above 800 g / mol.

12. Use according to one or more of claims 1 to 11, wherein as cold flow improver C) copolymers of ethylene and 8 to 21 mol% olefinically unsaturated compounds selected from vinyl esters, acrylic esters, methacrylic esters, alkyl vinyl ethers and / or alkenes, are used, wherein said compounds may be substituted with hydroxyl groups and one or more of these comonomers may be included in the polymer, and the cold flow improvers C) have at least 1 mole% higher comonomer content over the nucleators of group B).

13. Use according to claim 12, wherein as cold flow improver C) copolymers of ethylene and 8 to 21 mol% of vinyl esters of the formula 1 are used

CH ₂ = CH-OCOR ¹ (1)

wherein R ^{1 is} Ci to C ₃ o-alkyl, and said alkyl groups may be substituted with one or more hydroxyl groups.

14. Use according to claim 13, wherein R ^{1 is} a branched alkyl radical or a neoalkyl radical having 7 to 11 carbon atoms.

15. Use according to claim 13 and / or 14, wherein the ethylene copolymers vinyl acetate and at least one further vinyl ester of the formula 1, wherein R ^{1 is} C ₄ to C ₃₀ alkyl.

16. Use according to one or more of claims 1 to 15, wherein as cold flow improver C) oil-soluble polar nitrogen compounds are used, which reaction products of compounds of the formula NR ⁶ R ⁷ R ⁸ , wherein R ⁶ , R ⁷ and R ^{8 are the} same or different and at least one of these groups for C ₈ -C ₃₆ alkyl, C ₆ -C ₃₆ cycloalkyl, C ₈ -C ₃₆ alkenyl, in particular Ci ₂ -C ₂₄ alkyl, Ci ₂ -C ₂₄ alkenyl or Cyclohexyl, and the other groups are either hydrogen, C ₁ -C ₃₆ -alkyl, C ₂ -C ₃₆ -alkenyl, cyclohexyl, or a group of the formulas - (AO) _x -E or - (CH ₂ ) _n -NYZ, wherein a stands for an ethyl or propyl group, x is a number from 1 to 50, e = H, Ci-C ₃₀ alkyl, C ₅ cycloalkyl or C ₂ -C ₆ -C ₃₀ aryl, and n = 2, 3 or 4, and Y and Z independently of one another are H, C ₁ -C _{3 (r is} alkyl or - (AO) _x , with compounds which contain at least one acyl group.

17. Use according to one or more of claims 1 to 16, wherein as Kaltfließverbesserer C) alkylphenol-aldehyde resins are used which condensation products of alkylphenols with one or two alkyl radicals in the ortho and / or para position to the OH group with aldehydes 1 to 12 carbon atoms.

18. Use according to one or more of claims 1 to 17, wherein it acts as the nucleator for the paraffin crystallization substantially linear hydrocarbons having at least 20 carbon atoms B) are alkanes and / or alkenes.

19. Use according to one or more of claims 1 to 18, wherein the substantially linear hydrocarbons have molecular weights between about 280 and 2,800 g / mol.

20. Use according to one or more of claims 1 to 19, wherein it is the n-paraffins in the substantially linear hydrocarbons B).

21. Use according to one or more of claims 1 to 20, wherein the substantially linear hydrocarbons B) are mixtures of hydrocarbons of different chain lengths.

22. Use according to one or more of claims 1 to 21, wherein the substantially linear hydrocarbons B) are gas oil fractions in the boiling range from 300 to 550 ^° C., which have a content of n-paraffins of at least 10% by weight. exhibit.

23. Use according to one or more of claims 1 to 21, wherein the substantially linear hydrocarbons B) are paraffins from the dewaxing of mineral oil fractions.

24. Use according to one or more of claims 1 to 23, wherein it is the microcrystalline waxes having a melting range between 40 and 90 ⁰ C in the substantially linear hydrocarbons B).

Use according to one or more of claims 1 to 22 and 24, wherein the substantially linear hydrocarbons B) are waxes prepared by the Fischer-Tropsch process.

26. Use according to one or more of claims 1 to 25, wherein it is the α-olefins in the substantially linear hydrocarbons B).

27. Use according to one or more of claims 1 to 26, wherein the chain length of the substantially linear hydrocarbons B) is in the range of C22-C100.

28. Use according to one or more of claims 1 to 27, wherein the quantitative ratio between detergent additive A) and acting as Nucleator for Paraffinkristallisation substantially linear hydrocarbons having at least 20 C-atoms B) in the additized oil at 0.01 to 10 parts by weight on nucleator per part by weight of detergent additive, in each case based on the active ingredient.

29. Additives, containing

a) at least one ashless, nitrogen-containing detergent additive A), which is an oil-soluble, amphiphilic compound comprising at least one alkyl or alkenyl radical bonded to a polar group, wherein the alkyl or alkenyl radical has 10 to 500 carbon atoms and the polar group comprises 2 or more nitrogen atoms,

and

b) at least one oil-soluble compound B) acting as nucleator for the paraffin crystallization, selected from essentially linear hydrocarbons having at least 20 C atoms.

30. Additives according to claim 29, comprising a different from B) Mineralölaltfließverbesserer C).

31. Additives according to claim 30, wherein the mineral oil flow improver C) is selected from the compounds described in one or more of claims 12 to 17.

32. middle distillates having a sulfur content of less than 100 ppm and a 90% distillation point of below 360 ⁰ C, containing

a) at least one ashless, nitrogen-containing detergent additive A), which is an oil-soluble, amphiphilic compound comprising at least one alkyl or alkenyl radical bonded to a polar group, wherein the alkyl or alkenyl radical has 10 to 500 carbon atoms and the polar group comprises 2 or more nitrogen atoms,

b) at least one oil-soluble, acting as Nucleator for the paraffin crystallization compound B) selected from substantially linear hydrocarbons having at least 20 C-atoms, and

c) at least one mineral oil flow improver C) other than B).