WO2008155089A1 - 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 comb polymers that carry alkyl side chains having on average a length of at least 18 C atoms per mole for improving the response of cold flow improvers for mineral oils C), which are different from B), 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. Frequently, the filterability measured as CFPP with cold flow improvers of additized oils in the cold is often significantly reduced and can only be compensated for by greatly increased metering 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, acting as nucleator for the paraffin crystallization compound B), selected from

Comb polymers bearing alkyl carbon chains of at least 20 carbon atoms in length to improve the response of mineral oil flow improvers C) other than 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, wherein the alkyl or alkenyl radical is 10 to 500 carbon atoms and the polar group is 2 or more nitrogen atoms includes.

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 to the oil at least one oil-soluble compound B), which acts as a nucleator for paraffin crystallization, selected from comb polymers carrying alkyl side chains of at least 20 carbon atoms, 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 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, as Nucleator for the paraffin crystallization acting compound B), selected from comb polymers carrying alkyl side chains with a length of at least 20 carbon 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 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 compound B) acting as nucleator for paraffin crystallization, selected from comb polymers bearing alkyl side chains of at least 20 carbon atoms in length, and

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

The improvement in the response of cold flow improvers C) according to the invention is understood to improve at least one cold property of middle distillates adjusted or adjustable by cold flow improver C) and adversely affected by the addition of a detergent additive A) by addition of a compound B) acting as a nucleating agent for the paraffin crystallization , 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.

Especially affected is the response of flow improvers in middle distillates containing more than 10 ppm of a nitrogen containing detergent additive A), in particular more than 20 ppm and especially more than 40 ppm such as 50 to 2,000 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 the 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 has 15 to 500 carbon atoms and in particular 20 to 350 carbon atoms, for example 50 to 200 carbon 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 include: 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 succinamides and imides, and mixtures of these classes of compounds.

The detergent additives linked via CN bonds are preferably alkyl polyamines 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) in Means 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 alkenylsuccinic anhydrides with polyamines leads to products containing one or more amide and / or imide bonds per polyamine and, depending on the degree of maleation, one or two polyamines per

Can carry alkyl. Preferably, for the reaction of 1, 0 to 1, 7 and in particular 1, 1 to 1, 5 mol alkenyl succinic anhydride per mole of polyamine used, so that free primary amino groups remain in the product. In a further preferred embodiment, alkenyl succinic anhydride and polyamine are reacted equimolarly. In the implementation of polyamines with

Alkenylsuccinic anhydrides having a high degree of acylation of 1, 1 or more anhydride groups per alkyl radical, such as, for example, 1, 3 or more anhydride groups per alkyl radical, also give rise to polymers which 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. Oil-soluble Mannich reaction products based on polyolefin-substituted phenols and polyamines also 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) followed by condensation of the alkylphenol with aldehydes with 1 to 6 C 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 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 comb polymers B) acting as nucleator for the paraffin crystallization are polymers which carry alkyl side chains bonded to the polymer backbone and have a length of at least 20 carbon atoms. Particularly preferred are those polymers which carry side chains having 22 to 60, such as 24 to 45 carbon atoms. The proportion of these alkyl side chains in the total amount of the alkyl side chains of the polymer is at least 10 mol%, preferably at least 25 mol% and in particular at least 50 mol%, for example at least 80 mol%. Preferably, the side chains are linear or have at least correspondingly long linear segments.

The polymer backbone may for example be composed of ethylenically unsaturated mono- and / or polycarboxylic acids such as, for example, acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid. In addition, there may be more Monomers such as olefins, vinyl esters and / or vinyl ethers. Particular preference is given to copolymers based on fumaric acid and vinyl acetate and those based on maleic acid and α-olefins.

The polymer backbone carries long-chain alkyl radicals with a molar average of at least 18, preferably at least 20, such as at least 24 C atoms. As in the case of α-olefins, the alkyl radicals can be bonded directly to the backbone via a C-C bond or can be bound to the polymer backbone via an ester, amide, imide or ammonium group. Furthermore, the alkyl radicals can be bonded to the polymer backbone via spacers such as, for example, polyoxyalkylene or polyalkyleneamine groups having in each case 1 to 200 and in particular 2 to 50 oxyalkyl or alkylenamine units.

As nucleator suitable for the paraffin crystallization comb polymers B) are, for example, polymers of the formula (1)

(1 )

Mean in it

AR ¹ , COOR ¹ , OCOR ¹ , FT-COOR ¹ , OR ¹ ;

DH, CH _3, A or R ";

E H, A;

G H, R ", R" -COOR \ 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 at least 20 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.

Preferred 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. Particularly preferred olefins are α-olefins having at least 22 and especially 24 to 60 carbon atoms such as C ₂ o-α-olefin, C ₂₄ -α-olefin, C ₂₆ -α-olefin and mixtures thereof such as C ₂ o _-24 -α-olefin, C ₂₆ - ₂₈ -α-olefin or C _24-2S - α-olefin as well as technical chain sections in the region C ₃₀ +. By α-olefins are meant linear alkenes with terminal double bond. A particularly preferred comonomer vinyl ester is vinyl acetate. Usually, the copolymers of unsaturated carboxylic acids are essentially alternating copolymers.

Usually, these copolymers of ethylenically unsaturated carboxylic acids are esterified with alcohols to at least 50%, preferably to 60-100% and in particular to 70-98%, for example to 80-95%. Alcohols having at least 20 and preferably having at least 22 carbon atoms are preferably used for this purpose. However, it is also possible to use shorter-chain alcohols having, for example, 10 to 18 and especially 12 to 16 C atoms for the esterification, provided that the polymer already carries a sufficient amount of long side chains with at least 20 C atoms.

Further preferred comb polymers are homo- and copolymers of

Alkyl acrylates, alkyl methacrylates and alkyl vinyl ethers derived from alcohols having at least 20 and especially 22 to 60 carbon atoms such as 24 to 40 carbon atoms, and homopolymers and copolymers of alkyl vinyl esters derived from fatty acids having at least 20 and especially 22 to 40 Derive C atoms. In a further preferred embodiment, copolymers of dicarboxylic acids, such as maleic or fumaric acid and vinyl acetate, which have been esterified with long-chain fatty alcohols having at least 20 carbon atoms, are used as comb polymers. In the case of copolymers contain at least 10 mol%, preferably at least 25 mol% and in particular at least 50 mol% such as at least 80 mol% of the monomers alkyl chains having at least 20 carbon atoms and preferably 22 to 60 such as 24 to 45 carbon atoms.

Further preferred comb polymers are polycondensates containing structural units derived from alkylaromatics. These are in particular 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 may be the same or different in the case of the alkylphenol-aldehyde resins which can be used in the process according to the invention, they may be saturated or, preferably, unsaturated

At least 10 mol%, preferably at least 25 mol% and in particular at least 50 mol%, for example at least 80 mol% of the alkyl radicals of the alkylphenol resins suitable according to the invention as nucleator B) have alkyl chains with at least 20 carbon atoms and preferably between 22 and 60 such as 24 to 45 carbon atoms. On a molar average, the alkyl radicals have at least 18, preferably 20 to 60, such as 24 to 45 carbon atoms. 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 mixtures of C ₂ o _/ 22/24 -alkylphenols, C _24/26/2 β-alkylphenols and alkylphenols with chain lengths of C ₃₀ and higher have proven particularly suitable.

Suitable alkylphenol resins can also structural units of further

Phenolic analogs such as salicylic acid, hydroxybenzoic acid and their derivatives such as esters, amides and salts or consist of them. That is, the Alkyl radicals may be bonded to the phenol directly via a C-C bond or via an ester or ether group.

Preferred polycondensates are accessible by reacting alkylphenols with aldehydes and / or ketones. 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 polycondensation can also be carried out in the presence of aldehydes and amines in the form of a Mannich reaction. In a preferred embodiment of the invention, the compounds suitable as nucleator B) are alkylphenol-formaldehyde resins which contain oligomers or polymers having a repeating structural unit of the formula (2)

wherein R ^{11 is} C ₂₀ -C ₂₀ -alkyl-I or -alkenyl, OR ¹⁰ or 0-C (O) -R ¹⁰ , R ^{10 is} C ₂₀ -C ₂₀₀ -alkyl or -alkenyl and n is a number of 5 to 200 is included. R ¹⁰ is preferably C ₂₂ -C 30 -alkyl or -alkenyl and in particular C ₂₄ -C ₅₀ -alkyl or -alkenyl. ¹¹ Most preferably R is C ₂₂ -C ₀₀ alkyl or alkenyl and especially C ₂₄ -C ₅₀ alkyl or alkenyl. Preferably n is a number from 7 to 100 and especially for a number from 10 to 50.

These alkylphenol-aldehyde resins are accessible by known methods, for. B. by condensation of the corresponding alkylphenols with formaldehyde, ie with 0.5 to 1.5 MoI _1, preferably 0.8 to 1.2 moles of formaldehyde per mole of alkylphenol. The condensation can be carried out solvent-free, but preferably it is carried out in the presence of an inert 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, in particular aromatics such as toluene, xylene diethylbenzene and higher boiling commercial solvent mixtures such as Shellsol ^® AB, and solvent naphtha are 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 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 are common 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 ₈ -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. The molecular weight of the comb polymers B) preferred as nucleators for paraffin crystallization by gel permeation chromatography against poly (styrene) standards in THF is preferably 1,000-100,000 g / mol, particularly preferably 2,000-50,000 g / mol and especially 2,500-25,000 g / mol for example 3,000-20,000 g / mol. The prerequisite here is that the comb polymers, at least in application-relevant concentrations of 0.001 to 1 wt .-% are oil-soluble.

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 come into consideration, preferably ethylene copolymers (component III) or mixtures thereof with one or more of the constituents IV to VII are used , Mixtures of ethylene copolymers (constituent III) and alkylphenol-aldehyde resins (constituent V) and of ethylene copolymers (constituent III) and comb polymers (constituent VI) have proven particularly useful. 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, where the mentioned compounds may be substituted with 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} Ci to C _ß o-alkyl, preferably C ₄ to Ciβ-alkyl, especially C ₆ - to Ci 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 containing vinyl acetate and at least one further Vinylester of formula 1 wherein R ¹ is C ₄ to C ₃ -alkyl, preferably C ₄ to Ciβ alkyl, especially C ₆ - to C ₂ alkyl is ,

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- ₂ alkyl. Suitable acrylic esters include, for. B. 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 to C ₃₀ alkyl, preferably C ₄ ⁴ Cr - to C ₆ -alkyl, in particular C ₆ - to C ₂ is 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 methylnorbornene and vinylnorbornene. 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%. Other particularly preferred copolymers contain, in addition to ethylene and 8 to 18 moI% vinyl esters of C ₂ - to C _2-carboxylic acids 0.5 to 10 mol% olefins, such as propene, butene, isobutylene, hexene, 4-methylpentene, octene, diisobutylene and / or norbornene.

Preferably, these ethylene-co- and terpolymers have melt viscosities at 140 ⁰ C from 20 to 10,000 m-Pas, in particular from 30 to 5,000 m-Pas, especially from 50 to 2,000 m-Pas. 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. Such additive and oil mixtures preferably 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 , wherein R ⁶ , R ⁷ and R ^{8 may be the} same or different, and at least one of these groups is C ₆ -C ₃₆ -alkyl, C ₆ -C ₃₆ cycloalkyl

C ₈ -C ₃₆ -alkenyl, in particular C ₂ -C ₂₄ alkyl, C ₁₂ -C ₂₄ -alkenyl or cyclohexyl, and the remaining groups are either hydrogen, Ci-C ₃₆ alkyl, C ₂ -C ₃₆ alkenyl, Cyclohexyl, or a group of the formulas - (AO) _x -E or - (CH ₂ J _n -NYZ mean, in which A stands for an ethyl or propyl group, x is a number from 1 to 50, E = H, C ₁ -C ₃₀ -alkyl, C ₅ -C ₂ -cycloalkyl or C ₆ -C ₃ o-aryl, and n = 2, 3 or 4, and Y and Z independently of one another are H, C ₁ -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. Preferably, they are linear and substantially saturated, that is they have iodine numbers of less than 75 gb / g, preferably less than 60 gl ₂ / g and in particular between 1 and 10 gl ₂ / g. Especially preferred secondary fatty amines, in which two of the groups R ^6, R ⁷ and R ⁸ is C ₈ -C ₃₆ -alkyl, C ₆ -C ₃₆ cycloalkyl, C ₈ -C ₃₆ -alkyl are -alkenyl, in particular C ₂ -C ₂₄ alkyl, Ci ₂ -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 e.g. Coco fatty amine, tallow fatty amine, hydrogenated tallow fatty amine, dicoco fatty amine, ditallow fatty amine and di (hydrogenated tallow fatty amine). Particularly preferred amine derivatives are amine salts, imides and / or amides such as, for example, 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. Suitable carboxylic acids are, for example, maleic, fumaric, crotonic, itaconic and succinic acids, Ci-C ₄ o-alkenylsuccinic, adipic, glutaric, sebacic, and malonic acids and benzoic, phthalic, trimellitic and pyromellitic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid and their 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 particularly suitable as polymeric carbonyl compounds, particular preference is given to copolymers of maleic anhydride. Suitable comonomers are those which impart oil solubility to the copolymer. Oil-soluble is understood here to mean that the copolymer, after reaction with the fatty amine, becomes practically relevant

Dosing rates residue-free dissolved in the middle distillate to be added. 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 aminoalkylenepolycarboxylic acids 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, which may optionally be reacted with primary monoalkylamines and / or aliphatic alcohols (see EP-AO 154 177, EP-O 777 712), the reaction products of Alkenylspirobislactonen with Amines (see EP-AO 413 279 B1) and according to EP-AO 606 055 A2 reaction products of terpolymers based α.β-unsaturated dicarboxylic acid anhydrides, α, β-unsaturated compounds and polyoxyalkylene ethers of lower unsaturated alcohols.

The mixing ratio between the inventive ethylene copolymers III and oil-soluble polar nitrogen compounds as constituent 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 (which are generally understood to mean hydrocarbon radicals as defined below for constituent V) may be the same or different in the alkylphenol-aldehyde resins which can be used in the process according to the invention, they may be saturated or unsaturated and have preferably 1-20, in particular 4-16 such as 6 to 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 1500-3,000 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 which contain oligomers or polymers having a repeating structural unit of the formula (3)

wherein R ^{12 is} C _r C ₁₈ alkyl or alkenyl, OR ¹³ or 0-C (O) -R ¹³ , R ^{13 is} C ¹ -C ₁₈ alkyl or alkenyl and n is a number from 2 to 100. R ¹³ is preferably C 1 -C 6 -alkyl or -alkenyl and in particular C ₄ -C ₆ alkyl or alkenyl such as for C ₆ -C ₂ alkyl or alkenyl. Particularly preferably, R ¹² is CrC-iβ alkyl or alkenyl and especially C ₄ -C ₆ 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 also accessible by the methods described above for compounds B)

Also suitable as flow improvers comb polymers (component VI), for example, by the formula (4)

QHH

D M N (4)

to be discribed. Mean in it

QR ¹ ", COOR ¹ ", OCOR ¹ ", R" -COOR ', OR "¹; DH, CH ₃ , A or R"; EH ₁ A; GH, R ", R" -COOR '", an aryl radical or a heterocyclic radical; MH, COOR", OCOR ", OR", COOH; NH, R ", COOR", OCOR, an aryl radical; R " ^{1 is} a hydrocarbon chain having 8 to 18, preferably 10 to

16 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. Particularly suitable olefins are α-olefins having 10 to 18 and especially 12 to 16 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. A particularly suitable vinyl ester is, for example, vinyl acetate. Usually, these copolymers are at least 50% esterified with alcohols having 10 to 18 and especially 12 to 16 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) which are derived from alcohols having 10 to 18 and especially 12 to

16 C atoms derived as well as poly (vinyl esters), which are derived from fatty acids with 10 to 18 and especially 12 to 16 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 independently of one another have 16 to 26 C atoms, for example 17 to 24 C 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.

Polyols which are particularly suitable 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, for example 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 core 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, arachic and behenic, oleic and erucic acid, palmitoleic, myristoleic, ricinoleic acid and 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. Preferably, less than 50 mol% of the fatty acids used for the esterification contain 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 C 1 to C ₅ esters. Alkenylsuccinic acid and its derivatives with alkyl radicals having 8 to 200, in particular 10 to 50, C 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 formed, for example, by oxidation or by

Conversion with dicarboxylic acids converted into terminal carboxyl groups. By reaction with fatty alcohols having 8 to 50, in particular 12 to 30, especially 16 to 26 carbon atoms, polyoxyalkylene esters according to the invention are likewise obtained. 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, the above-mentioned proportions of Contain poly (alkylene oxides) and whose fatty alcohol and fatty acid above alkyl chain lengths and saturation degrees, are suitable according to the invention.

Furthermore, the alkoxylated polyols described above can be converted by etherification with fatty alcohols having 8 to 50, in particular 12 to 30, especially 16 to 26 C-atoms in accordance with the invention suitable polyoxyalkylene compounds. 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 ₁₇ -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 especially sorbitan 25-ethylene oxide tetrabehenate; 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 0.1 to 3 parts by weight of the comb polymer B) 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. Middle distillates, in particular mineral oils refer to those which are obtained by distillation of crude oil, in the range of about 150 to 450 ⁰ C and in particular in

Range from about 170 to 390 ^C 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 .-% of n-paraffins, of which the longer-chain Crystallize on cooling and 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 .-%. The compositions according to the invention are furthermore particularly advantageous 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 ⁰ have C and in special cases below 340 ⁰ C and further in middle distillates, the Siedebreiten between 20 and 90% distillation volume of 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 Also referred to as biodiesel fatty acid alkyl esters 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 is readily available by squeezing rapeseed. 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, dehazem, demulsifiers, dispersants, defoamers, dyes, corrosion inhibitors, lubricity additives, sludge inhibitors, odorants and / or cloud point depressants. Examples

Improvement of the cold flowability of middle distillates

To assess the effect of the additives of the invention on the

Cold flow properties of middle distillates were used detergent additives (A) with different nucleators (B) and other flow improvers (C) with the characteristics given below.

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 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 middle distillates added with the additive components listed in the table were cooled to -13 ° C. in a cold cabinet at -2 ° C./hour in a 200 ml graduated cylinder and stored at this temperature for 16 hours. 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 (CP _K s) 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. The dosage rates given in Tables 2 to 4 for the detergent additives A) and nucleators B) relate to the active ingredients used.

(B) Characterization of the inserted nucleators

B1) alternating copolymer of maleic anhydride and a mixture of equal parts of C 22 and C ₂₄ -α-olefin, esterified with 1, 5 mole equivalent per mole of anhydride of a mixture parts eicosanol, and docosanol,

50% in higher boiling aromatic solvent

B2) C ₂ o-24-alkylphenol-formaldehyde resin, 50% in higher boiling aromatic solvent

(C) Characterization of the further flow improvers used

C1) terpolymer of ethylene, 13 mol% vinyl acetate and 2 mol% vinyl neodecanoate with a measured at 140 ⁰ 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% vinyl acetate with a measured at 140 ⁰ C melt viscosity V140 of 125 m-Pas, 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 di-tallow fatty amine to the amide ammonium salt, prepared according to EP 0 398 101, 50% in 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 pentaethylenehexamine according to Table 2, Example 4 and detergent additive A2 as 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

OO

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

Ade Jitive test oil 2

Example ABC CFPP [ ⁰ C]

14 (VI) - - 75 ppm C2 - -14

15 (VgI.) - - 100 ppm C2 - -19

16 (VgI.) - - 150 ppm C1 - -20

17 (VI) - - 75 ppm C1 150 ppm C3 -21

18 (VgI.) - - 100 ppm C1 150 ppm C3 -29

19 (VgI.) - - 150 ppm C1 150 ppm C3 -31

20 (Cf.) 50 ppm A1 - 75 ppm C1 150 ppm C3 -14

21 (Cf.) 50 ppm A1 - 100 ppm C1 150 ppm C3 -19

22 (Cf.) 50 ppm A1 - 150 ppm C1 150 ppm C3 -20

23 (Cf.) 50 ppm A1 - 150 ppm C1 250 ppm C3 -20

24 50 ppm A1 30 ppm B1 75 ppm C1 150 ppm C3 -20

25 50 ppm A1 40 ppm B1 100 ppm C1 150 ppm C3 -30

26 50 ppm A1 40 ppm B1 100 ppm C1 150 ppm C3 -31

27 (See) 50 ppm A2 - 75 ppm C1 150 ppm C4 -15

28 (Cf.) 50 ppm A2 - 100 ppm C1 150 ppm C4 -12

29 (Cf.) 50 ppm A2 - 150 ppm C1 150 ppm C4 -20

30 (Cf.) 50 ppm A2 - 150 ppm C1 250 ppm C4 -21

31 50 ppm A2 30 ppm B1 75 ppm C1 150 ppm C4 -22

32 50 ppm A2 30 ppm B1 100 ppm C1 150 ppm C4 -29

33 50 ppm A2 30 ppm B2 75 ppm C1 150 ppm C4 -21 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

1. Use of at least one oil-soluble compound, which acts as nucleator for paraffin crystallization, B) ₁ selected from comb polymers carrying alkyl side chains of at least 20 carbon atoms in length, for improving the response of mineral oil flow improvers C) other than 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.

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⁾

in which each R ⁹ independently of one another represents hydrogen, an alkyl or hydroxyalkyl radical having up to 24 C atoms, a polyoxyalkylene radical - (AO) _r or polyiminoalkylene radical - [AN (R ⁹ )] _S - (R ⁹ ), however, 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 represent 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% of 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.

13. Use according to claim 12, wherein as cold flow improver C) copolymers of ethylene and 8 to 21 mol% vinyl esters of 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 may be, and at least one of these groups for C ₈ -C ₃₆ alkyl, C ₆ -C ₃₆ cycloalkyl, C ₈ -C ₃₆ alkylene, in particular C ₁₂ -C ₂₄ alkyl, C ₂ -C ₂₄ alkenyl or cyclohexyl and the remaining groups are either hydrogen, C _r C ₃₆ alkyl, C ₂ -C ₃₆ alkenyl, cyclohexyl, or a group of the formulas - (AO) _x -E or - (CH ₂ J _n -NYZ in which a stands for an ethyl or propyl group, x is a number from 1 to 50, e = H, -C ₃₀ alkyl, C ₅ -C ₁₂ cycloalkyl or C ₆ -C ₃₀ aryl, and n = 2, 3 or 4 and Y and Z independently of one another are H, C 1 -C ₃₀ -alkyl or - (AO) _x , with compounds containing 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 CrCiβ-alkyl or alkenyl radicals in ortho and / or para position to OH Group with aldehydes having 1 to 12 carbon atoms.

18. The use according to claim 1, wherein the comb polymers acting as nucleator for the paraffin crystallization have a proportion of the alkyl side chains having at least 20 C atoms in the total amount of the alkyl side chains of the comb polymer of at least 10 mol%.

19. Use according to one or more of claims 1 to 18, wherein the comb polymers acting as Nucleator for paraffin crystallization carry side chains having 22 to 60 carbon atoms.

20. Use according to one or more of claims 1 to 19, wherein the alkyl side chains of the comb polymers are linear.

21. The use as claimed in one or more of claims 1 to 20, wherein the comb polymers acting as nucleator for the paraffin crystallization comprise a backbone of ethylenically unsaturated monocarboxylic acids, polycarboxylic acids or a mixture thereof.

22. Use according to one or more of claims 1 to 21, wherein the alkyl side chains of the comb polymers are bonded via an ester, amide, imide or ammonium group to the polymer backbone.

23. Use according to one or more of claims 1 to 20 and 22, wherein the comb polymers acting as Nucleator for Parafflnkristallisation are derived from alkylaromatic structural units containing polycondensates having alkyl radicals having at least 20 carbon atoms.

24. Use according to claim 23, wherein the alkyl radicals are bonded to the aromatic via a C-C bond or via an ester or ether group.

25. Use according to one or more of claims 1 to 24, wherein the amount ratio between detergent additive A) and acting as Nucleator for the paraffin crystallizing comb polymer B) in the additized oil at 0.01 to

10 parts by weight of nucleator per part by weight of detergent additive, in each case based on the active ingredient.

26. 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 nucleator for paraffin crystallization acting compound B) selected from comb polymers carrying alkyl side chains of at least 18 carbon atoms in the molar average.

27. Additive according to claim 26, comprising a different from B) Mineralölaltfließverbesserer C).

28. Additives according to claim 26, wherein the mineral oil flow improver C) is selected from the compounds described in one or more of claims 12 to 17.

29. containing middle distillates with a sulfur content of less than 100 ppm and a 90% distillation point of below 360 ⁰ C ₁

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, the alkyl or alkenyl radical

10 to 500 carbon atoms and the polar group comprises 2 or more nitrogen atoms,

b) at least one oil-soluble compound B) acting as nucleator for the paraffin crystallization, selected from comb polymers which carry alkyl side chains with a length of at least 18 carbon atoms in the molar average, as well as

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