EP3481921B1 - Copolymers as additives for fuels and lubricants - Google Patents

Description

The present invention relates to new uses of copolymers for removing and/or reducing deposits in the fuel system and/or injection system of direct-injection diesel and/or gasoline engines.

The present invention relates to the use of certain copolymers as a fuel or lubricant additive; fuels and lubricants with additives; such as in particular as a detergent additive; Use of these copolymers to reduce or prevent deposits in the fuel systems and in particular injection systems of direct injection diesel engines, in particular in common rail injection systems, to reduce the fuel consumption of direct injection diesel engines, in particular diesel engines with common rail injection systems, and to minimize power loss (power loss) in direct injection diesel engines, especially in diesel engines with common rail injection systems; and as an additive for petrol, especially for the operation of DISI engines.

Background of the invention:

In direct-injection diesel engines, the fuel is injected through a multi-hole injection nozzle that reaches directly into the engine's combustion chamber and is finely distributed (nebulized), instead of being introduced into a pre-chamber or swirl chamber as in the classic (chamber) diesel engine. The advantage of direct-injection diesel engines lies in their high performance for a diesel engine and yet low consumption. In addition, these engines achieve a very high torque even at low speeds.

There are currently three main methods used to inject the fuel directly into the combustion chamber of the diesel engine: the conventional distributor injection pump, the pump-nozzle system (unit injector system or unit pump system) and the common rail system .

In the common rail system, the diesel fuel is pumped by a pump at pressures of up to 2000 bar into a high-pressure line, the common rail. Starting from the common rail, branch lines run to the various injectors, which inject the fuel directly into the combustion chamber. There is always full pressure on the common rail, which enables multiple injections or a special form of injection. With the other injection systems, on the other hand, only a smaller variation of the injection is possible. Common rail injection is essentially divided into three groups: (1.) Pre-injection, which essentially achieves softer combustion, so that hard combustion noise ("knocking") is reduced and the engine runs smoothly; (2.) Main injection, which is responsible in particular for a good torque curve; and (3.) post-injection, which in particular ensures a low NO _x value. At this After the post-injection, the fuel is usually not burned, but vaporized by the residual heat in the cylinder. The resulting exhaust gas/fuel mixture is transported to the exhaust system, where the fuel acts as a reducing agent for the nitrogen oxides NO _x in the presence of suitable catalysts.

With the common-rail injection system, the variable, cylinder-specific injection can have a positive effect on the pollutant emissions of the engine, eg the emission of nitrogen oxides (NO _x ), carbon monoxide (CO) and, in particular, particles (soot). This means, for example, that engines equipped with common rail injection systems can theoretically meet the Euro 4 standard even without an additional particulate filter.

In modern common-rail diesel engines, under certain conditions, for example when using fuels containing biodiesel or fuels with metal contamination such as zinc compounds, copper compounds, lead compounds and other metal compounds, deposits can form on the injector openings that affect the injection behavior of the fuel negatively affect the fuel and thereby impair the performance of the engine, i.e. in particular reducing the performance, but in some cases also worsening the combustion. The formation of deposits is increased by further structural developments of the injectors, in particular by changing the geometry of the nozzles (narrower, conical openings with a rounded outlet). In order for the engine and injectors to function optimally over the long term, such deposits in the nozzle openings must be prevented or reduced using suitable fuel additives.

Deposits in the injection systems of modern diesel engines cause significant performance problems. It is widely recognized that such deposits in the spray channels can lead to a reduction in the fuel flow and thus to power losses. Deposits on the injector tip, on the other hand, impair the optimal formation of fuel spray and thus cause poorer combustion and the associated higher emissions and increased fuel consumption. In contrast to these conventional, "external" deposit phenomena, "internal" deposits (collectively referred to as internal diesel injector deposits (IDID)) also prepare in certain parts of the injectors, especially on the nozzle needle, on the control piston, on the valve piston, on the valve seat the control unit and the guides of these components, increasing performance problems. Conventional additives show an insufficient effect against these IDIDs.

The “injection system” is understood to mean the part of the fuel system in motor vehicles from the fuel pump up to and including the injector outlet. The “fuel system” is understood to mean the components of motor vehicles that are in contact with the respective fuel, preferably the area from the tank up to and including the injector outlet.

It represents an embodiment of the present invention that the compounds according to the invention act against deposits not only in the injection system but also in the rest of the fuel system, here in particular against deposits in fuel filters and fuel pumps.

The WO 2011/146289 describes nitrogen-free additives of a substituted hydrocarbon having at least two carboxyl groups in free or anhydride form for improving the detergency in fuel systems. Examples include hydrocarbyl-substituted succinic anhydrides and hydrolyzed forms thereof.

Out of U.S.5766273 it is known that polymer mixtures containing copolymers of maleic anhydride and α-olefins as one component can be used as additives for mineral oil middle distillates to improve the flow properties, in particular the cloud point (CP) and the cold filter plugging point (CFPP).

U.S. 5,670,462 describes copolymers of maleic anhydride and C ₄ to C ₃₀ olefins. The use against deposits is not described.

JP 2007-077216 describes oils containing partial esters of copolymers of maleic anhydride and α-olefins with alkylene glycols. An effect of the copolymer against deposits is not described.

From the international patent application with the file number PCT/EP2014/076622 and filing date 4 December 2014 ( WO 2015/113681 ) it is known to use partially or fully hydrolyzed copolymers of maleic anhydride and α-olefins against engine deposits. The degree of hydrolysis in the examples is at least 15.9%.

Out of WO 16/83130 A1 it is known to react copolymers of at least one dicarboxylic acid or derivatives thereof, α-olefins and C ₃ -C ₂₀ -alkyl esters of (meth)acrylic acid with long-chain dialkylamines. The products obtainable in this way are used to reduce the crystallization of paraffin crystals in fuels, to improve the cold flow properties of fuel oils and to improve the filterability of fuel oils containing cold flow improver additives. The decisive parameters for effectiveness are the cold filter plugging point (CFPP) and a lowering of the cloud point (cloud point, CP), which is used to determine the precipitation of paraffins.

At the in the WO 16/83130 A1 The precipitates described are exclusively paraffins, i.e. components of fuels of fossil origin, which form at low temperatures during storage, but can be reversed by slightly heating the fuel. Those described in this document Deposits, on the other hand, only form under the conditions present in the injection or fuel system and in the presence of metals or as a result of polymerisation.

Out of CN 102382695A it is known to use copolymers of maleic anhydride, C ₁₂ -C ₁₈ -α-olefins and hexadecyl methacrylate to reduce the cold filter plugging point in diesel.

Other deposits are not described, nor is further derivatization or conversion of the anhydride functionalities of the copolymer disclosed.

The object of the present invention is to provide a new class of copolymer-based additives for use in modern diesel and gasoline fuels.

• in einem ersten Reaktionsschritt (I) Copolymerisation von
  1. (A) mindestens einer ethylenisch ungesättigten Mono- oder Dicarbonsäure oder deren Derivate, bevorzugt einer Dicarbonsäure oder deren Derivate, besonders bevorzugt dem Anhydrid einer Dicarbonsäure,
  2. (B) mindestens einem α -Olefin mit von mindestens 12 bis zu einschließlich 30 Kohlenstoffatomen,
  3. (C) optional mindestens einem weiteren, mindestens 4 Kohlenstoffatome aufweisenden, aliphatischen oder cycloaliphatischen Olefin, das ein anderes als (B) ist und
  4. (D) mindestens einem (Meth)acrylsäureester von Alkoholen, die mindestens 5 Kohlenstoffatome aufweisen,
     • wobei als Komponente (A) Maleinsäureanhydrid eingesetzt wird,
     • wobei das molare Einbauverhältnis im Copolymer von (A) / ((B) und (C)) (in Summe) von 10:1 bis 1:10 beträgt und
     • wobei der Anteil an einem oder mehreren der (Meth)acrylsäureester (D) bezogen auf die Menge der Monomere (A), (B) sowie optional (C) (in Summe) 5 bis 200 mol% beträgt, gefolgt von
• in einem zweiten Reaktionsschritt (II) teilweise oder vollständige Hydrolyse der im aus (I) erhaltenen Copolymer enthaltenen Anhydridfunktionalitäten und/oder teilweise Verseifung von im aus (I) erhaltenen Copolymer enthaltenen Carbonsäureesterfunktionalitäten, wobei mindestens 10% der Anhydridfunktionalitäten hydrolysiert werden und
  wobei das aus Reaktionsschritt (II) erhaltene Copolymer ein zahlenmittleres Molekulargewicht Mn von 0,5 bis 10 kDa aufweist,

zur Entfernung und/oder Verhinderung von Ablagerungen im Kraftstoffsystem und/oder Einspritzsystem von direkteinspritzenden Diesel- und/oder Benzinmotoren.The task is solved by
the use of copolymers available from

• in a first reaction step (I) copolymerization of
  1. (A) at least one ethylenically unsaturated mono- or dicarboxylic acid or derivatives thereof, preferably a dicarboxylic acid or derivatives thereof, particularly preferably the anhydride of a dicarboxylic acid,
  2. (B) at least one α -olefin having from at least 12 up to and including 30 carbon atoms,
  3. (C) optionally at least one further aliphatic or cycloaliphatic olefin having at least 4 carbon atoms, which is other than (B) and
  4. (D) at least one (meth)acrylic acid ester of alcohols having at least 5 carbon atoms,
     • maleic anhydride being used as component (A),
     • wherein the molar incorporation ratio in the copolymer of (A)/((B) and (C)) (total) is from 10:1 to 1:10 and
     • where the proportion of one or more of the (meth)acrylic esters (D) based on the amount of the monomers (A), (B) and optionally (C) (total) is 5 to 200 mol%, followed by
• in a second reaction step (II) partial or complete hydrolysis of the anhydride functionalities contained in the copolymer obtained from (I) and/or partial saponification of carboxylic acid ester functionalities contained in the copolymer obtained from (I), with at least 10% of the anhydride functionalities being hydrolyzed and
  wherein the copolymer obtained from reaction step (II) has a number-average molecular weight Mn of 0.5 to 10 kDa,

to remove and/or prevent deposits in the fuel system and/or injection system of direct injection diesel and/or petrol engines.

Such copolymers have been found to be effective in preventing and/or eliminating the following deposits in diesel and gasoline engines:

Summary of the invention:

These copolymers are characterized in particular by the fact that they work against a wide variety of deposits that impair the performance of modern diesel engines. The compounds according to the invention act, for example, against loss of performance both caused by the introduction of zinc and caused by the introduction of sodium into the diesel fuel. This essentially eliminates or avoids deposits in the spray channels and the injector tip. On the other hand, the compounds according to the invention also act against internal diesel injector deposits (IDID) caused by Na, Ca and/or K ions (so-called Na, Ca or K soaps IDID) and/or polymers deposits. Na, Ca and K soaps IDID are deposits that contain the relevant metal ions with any counterions. The polymeric deposits, on the other hand, are free of metal ions and can be traced back to high-molecular organic material that is either insoluble or insoluble in the fuel.

Character description:

figure 1 shows the sequence of a one-hour engine test cycle according to CEC F-098-08.

Description of the copolymer

The monomer (A) is maleic anhydride.

In the context of this document, C ₁ -C ₄ -alkyl is understood as meaning methyl, ethyl, isopropyl , n-propyl, n-butyl, isobutyl , sec -butyl and tert -butyl, preferably methyl and ethyl, particularly preferably methyl .

The monomer (B) is at least one, preferably one to four, particularly preferably one to three, very particularly preferably one or two and in particular precisely one α -olefin having from at least 12 up to and including 30 carbon atoms. The α -olefins (B) preferably have at least 14, particularly preferably at least 16 and very particularly preferably at least 18 carbon atoms. The α -olefins (B) preferably have up to and including 28, more preferably up to and including 26 and most preferably up to and including 24 carbon atoms.

The α-olefins can preferably be linear or branched, preferably linear, 1-alkenes.

Examples thereof are 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonodecene, 1-eicosene, 1-docosene, 1-tetracosene, 1-hexacosene , Of which 1-octadecene, 1-eicosene, 1-docosene and 1-tetracosene, and mixtures thereof are preferred.

Further examples of α -olefin (B) are those olefins which are oligomers or polymers of C ₂ - to C ₁₂ -olefins, preferably of C ₃ - to C ₁₀ -olefins, particularly preferably of C ₄ - to C ₆ olefins. Examples thereof are ethene, propene, 1-butene, 2-butene, isobutene, pentene isomers and hexene isomers, preference being given to ethene, propene, 1-butene, 2-butene and isobutene.

Mentioned specifically as α -olefins (B) are oligomers and polymers of propene, 1-butene, 2-butene, isobutene and mixtures thereof, especially oligomers and polymers of propene or isobutene or of mixtures of 1-butene and 2-butene. Among the oligomers, the trimers, tetramers, pentamers and hexamers and mixtures thereof are preferred.

In addition to the olefin (B), optionally at least one, preferably one to four, particularly preferably one to three, very particularly preferably one or two and in particular precisely one further, at least 4 carbon atoms, aliphatic or cycloaliphatic olefin (C), the one is other than (B), are polymerized into the copolymer of the invention.

The olefins (C) can be olefins with a terminal ( α ) double bond or those with a non-terminal double bond, preferably with an α double bond. The olefin (C) is preferably an olefin having from 4 to less than 12 or more than 30 carbon atoms. If the olefin (C) is an olefin having 12 to 30 carbon atoms, then this olefin (C) has no α double bond.

Examples of aliphatic olefins (C) are 1-butene, 2-butene, isobutene, pentene isomers, hexene isomers, heptene isomers, octene isomers, nonene isomers, decene isomers, undecene isomers and mixtures thereof .

Examples of cycloaliphatic olefins (C) are cyclopentene, cyclohexene, cyclooctene, cyclodecene, cyclododecene, α- or β -pinene and mixtures thereof, limonene and norbornene.

Further examples of olefins (C) are polymers of propene, 1-butene, 2-butene or isobutene containing more than 30 carbon atoms or olefin mixtures containing such, preferably isobutene or olefin mixtures containing such, particularly preferably having an average molecular weight M _w in the range from 500 to 5000 g/mol, preferably 650 to 3000, particularly preferably 800 to 1500 g/mol.

The oligomers or polymers containing isobutene in copolymerized form preferably have a high content of terminal ethylenic double bonds ( α double bonds), for example at least 50 mol %, preferably at least 60 mol %, particularly preferably at least 70 mol % and most preferably at least 80 mole percent.

Suitable isobutene sources for the preparation of such isobutene-containing oligomers or polymers are both pure isobutene and isobutene-containing C4 hydrocarbon streams, for example C4 raffinates, in particular "raffinate 1", C4 cuts from isobutane -Dehydrogenation, C4 cuts from steam crackers and from FCC crackers (fluid catalysed cracking), provided they are largely freed from the 1,3-butadiene contained therein. A C4 hydrocarbon stream from an FCC refinery unit is also known as a "b/b" stream. Other suitable isobutenic C4 hydrocarbon streams are, for example, the product stream of a propylene-isobutane co-oxidation or the product stream from a metathesis unit, which are generally used after customary purification and/or concentration. Suitable C4 hydrocarbon streams typically contain less than 500 ppm, preferably less than 200 ppm, butadiene. The presence of 1-butene and of cis- and trans-2-butene is largely uncritical. Typically, the isobutene concentration in the C4 hydrocarbon streams mentioned is in the range from 40 to 60% by weight. Thus, raffinate 1 generally consists essentially of 30 to 50% by weight isobutene, 10 to 50% by weight 1-butene, 10 to 40% by weight cis- and trans-2-butene and 2 to 35% by weight % butanes; in the polymerization process according to the invention, the unbranched butenes in raffinate 1 are generally practically inert and only the isobutene is polymerized. In a preferred embodiment, the monomer source used for the polymerization is a technical C4 hydrocarbon stream having an isobutene content of from 1 to 100% by weight, in particular from 1 to 99% by weight, in particular from 1 to 90% by weight. , more preferably from 30 to 60 wt.

In particular when using a raffinate 1 stream as the source of isobutene, the use of water as the sole or additional initiator has proven itself, especially when the temperature is from -20.degree. C. to +30.degree. C., in particular from 0.degree. C. to +20.degree C, polymerized. However, at temperatures from -20° C. to +30° C., in particular from 0° C. to +20° C., it is also possible to dispense with the use of an initiator when using a raffinate 1 stream as isobutene source.

Said isobutenic monomer mixture can contain small amounts of contaminants, such as water, carboxylic acids or mineral acids, without critical losses in yield or selectivity occurring. It is expedient to avoid accumulation of these impurities by removing such pollutants from the isobutene-containing monomer mixture, for example by adsorption on solid adsorbents such as activated carbon, molecular sieves or ion exchangers.

Although less preferred, it is also possible to react monomer mixtures of isobutene or the isobutene-containing hydrocarbon mixture with olefinically unsaturated monomers which are copolymerizable with isobutene. If monomer mixtures of isobutene are to be copolymerized with suitable comonomers, the monomer mixture preferably contains at least 5% by weight, more preferably at least 10% by weight and in particular at least 20% by weight of isobutene, and preferably at most 95% by weight, especially preferably at most 90% by weight and in particular at most 80% by weight of comonomers.

In a preferred embodiment, the substance mixture of the olefins (B) and optionally (C), averaged for their amounts, has at least 12 carbon atoms, preferably at least 14, particularly preferably at least 16 and very particularly preferably at least 17 carbon atoms.

For example, a 2:3 mixture of docosene and tetradecene has an average carbon atom value of 0.4 × 22 + 0.6 × 14 = 17.2.

The upper limit is less relevant and is usually no more than 60 carbon atoms, preferably no more than 55, more preferably no more than 50, most preferably no more than 45 and especially no more than 40 carbon atoms.

The monomer (D) is at least one, preferably one to three, particularly preferably one or two and very particularly preferably precisely one (meth)acrylic ester of alcohols which have at least 5 carbon atoms.

Preferred (meth)acrylic esters (Dc) are (meth)acrylic esters of C ₅ - to C ₁₈ -alkanols, preferably of n-pentanol, n-hexanol, n-heptanol, n-octanol, n-decanol, n-dodecanol (lauryl alcohol ), tridecanol isomer mixtures, n-tetradecanol, n-hexadecanol, heptadecanol isomer mixtures, n-octadecanol, 2-ethylhexanol or 2-propylheptanol. Dodecyl acrylate, 2-ethylhexyl acrylate and 2-propylheptyl acrylate are particularly preferred.

In a particular embodiment, the alcohol is a mixture of alcohols containing 13 carbon atoms, particularly preferably obtainable by oligomerization of C ₂ -C ₆ -olefins, in particular C ₃ - or C ₄ -olefins, and subsequent hydroformylation.

In a further particular embodiment, the alcohol is a mixture of alcohols having 17 carbon atoms, particularly preferably one that can be obtained by hydroformylation from a C ₁₆ olefin mixture, which in turn can be obtained by oligomerization of an olefin mixture that contains predominantly four Contains hydrocarbons containing carbon atoms.

On average, this olefin mixture has from 15 to 17 carbon atoms, preferably from 15.1 to 16.9, particularly preferably from 15.2 to 16.8, very particularly preferably from 15.5 to 16.5 and in particular from 15.8 to 16.2 .

In a very particularly preferred embodiment, this alcohol has an average degree of branching, measured as the ISO index, of 2.8 to 3.7.

In particular, this alcohol is obtained by a process as described in WO 2009/124979 A1 , there in particular page 5, line 4 to page 16, line 29, and the examples from page 19, line 19 to page 21, line 25, which is hereby incorporated by reference into the present disclosure.

According to this preferred process, a C ₁₇ -alcohol mixture having particularly advantageous performance properties can be prepared as the product of the transition metal-catalyzed oligomerization of olefins having 2 to 6 carbon atoms. In this process, a C ₁₆ -olefin mixture is first isolated from the product of the olefin oligomerization by distillation and only then is this C ₁₆ -olefin mixture subjected to hydroformylation. It is thus possible to provide a more highly branched C ₁₇ -alcohol mixture with particularly advantageous performance properties.

The incorporation ratio of the monomers (A) and (B) and (D) and optionally (C) in the copolymer obtained from the reaction step (I) is as follows:
The molar ratio of (A)/((B) and (C)) (total) is from 10:1 to 1:10, preferably from 8:1 to 1:8, particularly preferably from 5:1 to 1:5, very particularly preferably 3:1 to 1:3, in particular 2:1 to 1:2 and especially 1.5:1 to 1:1.5. For the special case of maleic anhydride as monomer (A), the molar incorporation ratio of maleic anhydride to monomers ((B) and (C)) (total) is about 1:1. In order to achieve complete conversion of the α -olefin (B), it can nevertheless be useful to use maleic anhydride in a slight excess over the α -olefin, for example 1.01-1.5:1, preferably 1.02-1.4 :1, particularly preferably 1.05-1.3:1, very particularly preferably 1.07-1.2:1 and in particular 1.1-1.15:1.

The molar ratio of the obligate monomer (B) to the monomer (C), if present, is generally from 1:0.05 to 10, preferably from 1:0.1 to 6, particularly preferably from 1:0. 2 to 4, very particularly preferably from 1:0.3 to 2.5 and especially 1:0.5 to 1.5.

In a preferred embodiment, no optional monomer (C) is present in addition to monomer (B).

The proportion of one or more of the (meth)acrylic esters (D) based on the amount of the monomers (A), (B) and optionally (C) (in total) is 5 to 200 mol%, preferably 10 to 150 mol%, particularly preferably 15 to 100 mol%, very particularly preferably 20 to 50 mol% and in particular more than 20 to 33 mol%.

In a particularly preferred embodiment, the copolymer consists of the monomers (A) and (B) and (D).

In a second reaction step (II), the anhydride or carboxylic acid ester functionalities present in the copolymer obtained from (I) can be partially or fully hydrolyzed and/or partially hydrolyzed. Preferably, in reaction step (II), anhydride functionalities are hydrolyzed and carboxylic acid ester functionalities are left substantially intact.

According to the invention, at least 10% of the anhydride functionalities present are hydrolyzed. Particularly preferably at least 25%, very particularly preferably at least 50%, in particular at least 75%, especially at least 85% and even at least 90% of the anhydride and carboxylic acid ester functionalities present are hydrolyzed or hydrolyzed. Preferably, in reaction step (II), anhydride functionalities are hydrolyzed and carboxylic acid ester functionalities are left substantially intact, so that reaction step (II) involves only hydrolysis but no saponification.

Preferably the anhydride functionalities are fully hydrolyzed, more preferably up to 99.9%, most preferably up to 99.5%, especially up to 99% and especially up to 95%.

For hydrolysis, the amount of water corresponding to the desired degree of hydrolysis, based on the anhydride functionalities present, is added and the copolymer obtained from (I) is heated in the presence of the added water. In the case of preferred complete hydrolysis of anhydride groups, more than the required equimolar amount of water can also be added, for example at least 1.05 times, preferably at least 1.1 times, particularly preferably at least 1.2 times and very particularly preferably at least 1.25 times the molar amount of water. As a rule, a temperature of preferably 20 to 150° C., preferably 60 to 100° C., is sufficient for this. If necessary, the reaction can be carried out under pressure in order to prevent water from escaping. Under these reaction conditions, the anhydride functionalities in the copolymer are generally reacted selectively, whereas any carboxylic acid ester functionalities present in the copolymer do not react, or at least react only to a minor extent.

For saponification, the copolymer is reacted with an amount of strong base in the presence of water equal to the degree of saponification desired.

Hydroxides, oxides, carbonates or bicarbonates of alkali metals or alkaline earth metals can preferably be used as strong bases.

The copolymer obtained from (I) is then heated in the presence of the added water and the strong base. A temperature of preferably 20 to 130° C., preferably 50 to 110° C., is generally sufficient for this. If necessary, the reaction can be carried out under pressure.

It is also possible to hydrolyze the carboxylic acid ester functionalities with water in the presence of an acid. The acids used are preferably mineral, carboxylic, sulfonic or phosphorus-containing acids with a pKa value of not more than 5, particularly preferably not more than 4.

Examples are acetic acid, formic acid, oxalic acid, salicylic acid, substituted succinic acids, benzenesulfonic acids substituted or unsubstituted on the aromatic compound, sulfuric acid, nitric acid, hydrochloric acid or phosphoric acid; the use of acidic ion exchange resins is also conceivable.

The copolymer obtained from (I) is then heated in the presence of the added water and acid. A temperature of preferably 40 to 200° C., preferably 80 to 150° C., is generally sufficient for this. If necessary, the reaction can be carried out under pressure.

If the copolymers obtained from step (II) still contain residues of acid anions, it may be preferable to remove these acid anions from the copolymer using an ion exchanger and preferably to exchange them for hydroxide ions or carboxylate ions, particularly preferably hydroxide ions. This is particularly the case when the acid anions contained in the copolymer are halides, contain sulfur or contain nitrogen. The copolymer obtained from reaction step (II) generally has a weight-average molecular weight Mw of 0.5 to 20 kDa, preferably 0.6 to 15, particularly preferably 0.7 to 7, very particularly preferably 1 to 7 and in particular 1, 5 to 54 kDa (determined by gel permeation chromatography with tetrahydrofuran and polystyrene as standards).

The number-average molecular weight Mn is from 0.5 to 10 kDa, preferably from 0.6 to 5, particularly preferably from 0.7 to 4, very particularly preferably from 0.8 to 3 and in particular from 1 to 2 kDa (determined by gel permeation chromatography with tetrahydrofuran and polystyrene as standard).

The polydispersity is generally from 1 to 10, preferably from 1.1 to 8, particularly preferably from 1.2 to 7, very particularly preferably from 1.3 to 5 and in particular from 1.5 to 3.

The content of free acid groups in the copolymer after reaction step (II) has been carried out is preferably less than 5 mmol/g copolymer, particularly preferably less than 3, very particularly preferably less than 2 mmol/g copolymer and in particular less than 1 mmol/g.

In a preferred embodiment, the copolymers contain a high proportion of adjacent carboxylic acid groups, as determined by measuring adjacency. For this purpose, a sample of the copolymer is annealed for a period of 30 minutes at a temperature of 290° C. between two Teflon foils and an FTIR spectrum is recorded at a bubble-free point. The IR spectrum of Teflon is subtracted from the spectra obtained, the layer thickness is determined and the content of cyclic anhydride is determined.

In a preferred embodiment, the adjacency is at least 10%, preferably at least 15%, particularly preferably at least 20%, very particularly preferably at least 25% and in particular at least 30%.

A preferred embodiment is to use the copolymers obtained from reaction steps (I) or (II), preferably the copolymers obtained from reaction step (II), without further chemical modification in the uses according to the invention or the additive concentrates or fuels according to the invention. This means that after the end of the last reaction step, further reactions which change the chemical structure of the copolymers obtained after the end of the last reaction step are ruled out.

use

The fuel to which additives have been added with the copolymer according to the invention is a gasoline fuel or, in particular, a middle distillate fuel, in particular a diesel fuel.

The fuel can contain other customary additives to improve effectiveness and/or suppress wear.

The described copolymers are often used in the form of fuel additive mixtures, together with the usual additives:
In the case of diesel fuels, these are primarily customary detergent additives, carrier oils, cold flow improvers, lubricity improvers, corrosion inhibitors other than the described copolymers, demulsifiers, dehazers, antifoams, cetane number improvers, combustion improvers, antioxidants or stabilizers, antistatic agents, metallocenes, metal deactivators , dyes and/or solvents.

• in einem ersten Reaktionsschritt (I) Copolymerisation von
  1. (A) mindestens einer ethylenisch ungesättigten Mono- oder Dicarbonsäure oder deren Derivate, bevorzugt einer Dicarbonsäure oder deren Derivate, besonders bevorzugt dem Anhydrid einer Dicarbonsäure,
  2. (B) mindestens einem α -Olefin mit von mindestens 12 bis zu einschließlich 30 Kohlenstoffatomen,
  3. (C) optional mindestens einem weiteren, mindestens 4 Kohlenstoffatome aufweisenden, aliphatischen oder cycloaliphatischen Olefin, das ein anderes als (B) ist und
  4. (D) mindestens einem (Meth)acrylsäureester von Alkoholen, die mindestens 5 Kohlenstoffatome aufweisen,
     • wobei als Komponente (A) Maleinsäureanhydrid eingesetzt wird,
     • wobei das molare Einbauverhältnis im Copolymer von (A) / ((B) und (C)) (in Summe) von 10:1 bis 1:10 beträgt und
     • wobei der Anteil an einem oder mehreren der (Meth)acrylsäureester (D) bezogen auf die Menge der Monomere (A), (B) sowie optional (C) (in Summe) 5 bis 200 mol% beträgt, gefolgt von
• in einem zweiten Reaktionsschritt (II) teilweise oder vollständige Hydrolyse der im aus (I) erhaltenen Copolymer enthaltenen Anhydridfunktionalitäten und/oder teilweise Verseifung von im aus (I) erhaltenen Copolymer enthaltenen Carbonsäureesterfunktionalitäten, wobei mindestens 10% der Anhydridfunktionalitäten hydrolysiert werden und
  wobei das aus Reaktionsschritt (II) erhaltene Copolymer ein zahlenmittleres Molekulargewicht Mn von 0,5 bis 10 kDa aufweist,

Accordingly, another object of the invention is the use of copolymers obtainable by

• in a first reaction step (I) copolymerization of
  1. (A) at least one ethylenically unsaturated mono- or dicarboxylic acid or derivatives thereof, preferably a dicarboxylic acid or derivatives thereof, particularly preferably the anhydride of a dicarboxylic acid,
  2. (B) at least one α -olefin having from at least 12 up to and including 30 carbon atoms,
  3. (C) optionally at least one further aliphatic or cycloaliphatic olefin having at least 4 carbon atoms, which is other than (B) and
  4. (D) at least one (meth)acrylic acid ester of alcohols having at least 5 carbon atoms,
     • maleic anhydride being used as component (A),
     • wherein the molar incorporation ratio in the copolymer of (A)/((B) and (C)) (total) is from 10:1 to 1:10 and
     • where the proportion of one or more of the (meth)acrylic esters (D) based on the amount of the monomers (A), (B) and optionally (C) (total) is 5 to 200 mol%, followed by
• in a second reaction step (II) partial or complete hydrolysis of the anhydride functionalities contained in the copolymer obtained from (I) and/or partial saponification of carboxylic acid ester functionalities contained in the copolymer obtained from (I), with at least 10% of the anhydride functionalities being hydrolyzed and
  wherein the copolymer obtained from reaction step (II) has a number-average molecular weight Mn of 0.5 to 10 kDa,

in additive packages containing at least one additive selected from the group consisting of detergent additives, carrier oils, cold flow improvers, lubricity improvers, corrosion inhibitors other than the described copolymers,

Demulsifiers, dehazers, anti-foaming agents, cetane number improvers, combustion improvers, antioxidants, stabilizers, antistatic agents, metallocenes, metal deactivators, dyes and solvents, to reduce the fuel consumption of direct injection diesel engines, in particular diesel engines with common rail injection systems and/or to minimize power loss (power loss ) in direct injection diesel engines, especially in diesel engines with common rail injection systems.

In the case of petrol, these are primarily lubricity improvers (friction modifiers), corrosion inhibitors other than the copolymers described, demulsifiers, dehazers, antifoams, combustion improvers, antioxidants or stabilizers, antistatic agents, metallocenes, metal deactivators, dyes and/or solvents.

• in einem ersten Reaktionsschritt (I) Copolymerisation von
  1. (A) mindestens einer ethylenisch ungesättigten Mono- oder Dicarbonsäure oder deren Derivate, bevorzugt einer Dicarbonsäure oder deren Derivate, besonders bevorzugt dem Anhydrid einer Dicarbonsäure,
  2. (B) mindestens einem α -Olefin mit von mindestens 12 bis zu einschließlich 30 Kohlenstoffatomen,
  3. (C) optional mindestens einem weiteren, mindestens 4 Kohlenstoffatome aufweisenden, aliphatischen oder cycloaliphatischen Olefin, das ein anderes als (B) ist und
  4. (D) mindestens einem (Meth)acrylsäureester von Alkoholen, die mindestens 5 Kohlenstoffatome aufweisen,
     • wobei als Komponente (A) Maleinsäureanhydrid eingesetzt wird,
     • wobei das molare Einbauverhältnis im Copolymer von (A) / ((B) und (C)) (in Summe) von 10:1 bis 1:10 beträgt und
     • wobei der Anteil an einem oder mehreren der (Meth)acrylsäureester (D) bezogen auf die Menge der Monomere (A), (B) sowie optional (C) (in Summe) 5 bis 200 mol% beträgt, gefolgt von
• in einem zweiten Reaktionsschritt (II) teilweise oder vollständige Hydrolyse der im aus (I) erhaltenen Copolymer enthaltenen Anhydridfunktionalitäten und/oder teilweise Verseifung von im aus (I) erhaltenen Copolymer enthaltenen Carbonsäureesterfunktionalitäten, wobei mindestens 10% der Anhydridfunktionalitäten hydrolysiert werden und
  wobei das aus Reaktionsschritt (II) erhaltene Copolymer ein zahlenmittleres Molekulargewicht Mn von 0,5 bis 10 kDa aufweist,

Accordingly, another object of the invention is the use of copolymers obtainable by

• in a first reaction step (I) copolymerization of
  1. (A) at least one ethylenically unsaturated mono- or dicarboxylic acid or derivatives thereof, preferably a dicarboxylic acid or derivatives thereof, particularly preferably the anhydride of a dicarboxylic acid,
  2. (B) at least one α -olefin having from at least 12 up to and including 30 carbon atoms,
  3. (C) optionally at least one further aliphatic or cycloaliphatic olefin having at least 4 carbon atoms, which is other than (B) and
  4. (D) at least one (meth)acrylic acid ester of alcohols having at least 5 carbon atoms,
     • maleic anhydride being used as component (A),
     • wherein the molar incorporation ratio in the copolymer of (A)/((B) and (C)) (total) is from 10:1 to 1:10 and
     • where the proportion of one or more of the (meth)acrylic esters (D) based on the amount of the monomers (A), (B) and optionally (C) (total) is 5 to 200 mol%, followed by
• in a second reaction step (II) partial or complete hydrolysis of the anhydride functionalities contained in the copolymer obtained from (I) and/or partial saponification of carboxylic acid ester functionalities contained in the copolymer obtained from (I), with at least 10% of the anhydride functionalities being hydrolyzed and
  wherein the copolymer obtained from reaction step (II) has a number-average molecular weight Mn of 0.5 to 10 kDa,

in additive packages containing at least one additive selected from the group consisting of lubricity improvers (friction modifiers), corrosion inhibitors other than the described copolymers, demulsifiers, dehazers, antifoams, combustion improvers, antioxidants, stabilizers, antistatic agents, metallocenes, metal deactivators, dyes and solvents, to reduce of deposits in the intake system of a gasoline engine, such as in particular DISI and PFI (Port Fuel Injector) engines.

Typical examples of suitable co-additives are listed in the following section:
B1) Detergent additives

• (Da) Mono- oder Polyaminogruppen mit bis zu 6 Stickstoffatomen, wobei mindestens ein Stickstoffatom basische Eigenschaften hat;
• (Db) Nitrogruppen, gegebenenfalls in Kombination mit Hydroxylgruppen;
• (Dc) Hydroxylgruppen in Kombination mit Mono- oder Polyaminogruppen, wobei mindestens ein Stickstoffatom basische Eigenschaften hat;
• (Dd) Carboxylgruppen oder deren Alkalimetall- oder Erdalkalimetallsalzen;
• (De) Sulfonsäuregruppen oder deren Alkalimetall- oder Erdalkalimetallsalzen;
• (Df) Polyoxy-C₂- bis C₄-alkylengruppierungen, die durch Hydroxylgruppen, Mono-oder Polyaminogruppen, wobei mindestens ein Stickstoffatom basische Eigenschaften hat, oder durch Carbamatgruppen terminiert sind;
• (Dg) Carbonsäureestergruppen;
• (Dh) aus Bernsteinsäureanhydrid abgeleiteten Gruppierungen mit Hydroxy-und/oder Amino- und/oder Amido- und/oder Imidogruppen; und/oder
• (Di) durch Mannich-Umsetzung von substituierten Phenolen mit Aldehyden und Mono- oder Polyaminen erzeugten Gruppierungen.

The customary detergent additives are preferably amphiphilic substances which have at least one hydrophobic hydrocarbon radical with a number-average Molecular weight (M _n ) from 85 to 20,000 and at least one polar moiety selected from:

• (Da) mono- or polyamino groups with up to 6 nitrogen atoms, where at least one nitrogen atom has basic properties;
• (Db) nitro groups, optionally in combination with hydroxyl groups;
• (Dc) hydroxyl groups in combination with mono- or polyamino groups, where at least one nitrogen atom has basic properties;
• (Dd) carboxyl groups or their alkali metal or alkaline earth metal salts;
• (De) sulfonic acid groups or their alkali metal or alkaline earth metal salts;
• (Df) polyoxy-C ₂ - to C ₄ -alkylene groups terminated by hydroxyl groups, mono- or polyamino groups, where at least one nitrogen atom has basic properties, or by carbamate groups;
• (Dg) carboxylic acid ester groups;
• (ie) moieties derived from succinic anhydride having hydroxy and/or amino and/or amido and/or imido groups; and or
• (Di) moieties generated by Mannich reactions of substituted phenols with aldehydes and mono- or polyamines.

The hydrophobic hydrocarbon residue in the above detergent additives, which provides sufficient solubility in fuel, has a number average molecular weight (M _n ) of 85 to 20,000, preferably 113 to 10,000, more preferably 300 to 5,000, more preferably 300 to 3,000, even more preferably from 500 to 2,500 and in particular from 700 to 2,500, especially from 800 to 1500. As a typical hydrophobic hydrocarbon radical, in particular in connection with the polar, in particular polypropenyl, polybutenyl and polyisobutenyl radicals with a number average molecular weight M _n of preferably from 300 to 5000, particularly preferably from 300 to 3000, more preferably from 500 to 2500, even more preferably from 700 to 2500 and in particular from 800 to 1500.

The following may be mentioned as examples of the above groups of detergent additives:
Additives containing mono- or polyamino groups (Da) are preferably polyalkenemono- or polyalkenepolyamines based on polypropene or highly reactive (ie with predominantly terminal double bonds) or conventional (ie with predominantly central double bonds) polybutene or polyisobutene with M _n =300 to 5000, especially preferably 500 to 2500 and in particular 700 to 2500. Such additives based on highly reactive polyisobutene, which can be prepared from the polyisobutene, which can contain up to 20% by weight of n-butene units, by hydroformylation and reductive amination with ammonia, monoamines or polyamines such as dimethylaminopropylamine, ethylenediamine, diethylenetriamine, triethylenetetramine or tetraethylenepentamine , are in particular from the EP-A 244 616 known. If you start out with the production of the additives from polybutene or polyisobutene with predominantly central double bonds (usually in the β and γ position), the production route offers itself by chlorination and subsequent amination or by oxidation of the double bond with air or ozone to the carbonyl or Carboxyl compound and subsequent amination under reductive (hydrogenating) conditions. Amines, such as e.g. B. ammonia, monoamines or the above polyamines can be used. Corresponding additives based on polypropylene are in particular in the WO-A 94/24231 described.

Other particular monoamino groups (Da) containing additives are the hydrogenation products of the reaction products of polyisobutenes with an average degree of polymerization P = 5 to 100 with nitrogen oxides or mixtures of nitrogen oxides and oxygen, as in particular in the WO-A 97/03946 are described.

Other special monoamino groups (Da)-containing additives are the compounds obtainable from polyisobutene epoxides by reaction with amines and subsequent dehydration and reduction of the amino alcohols, as they are in particular in DE-A 196 20 262 are described.

Additives containing nitro groups (Db), optionally in combination with hydroxyl groups, are preferably reaction products of polyisobutenes with an average degree of polymerization P=5 to 100 or 10 to 100 with nitrogen oxides or mixtures of nitrogen oxides and oxygen, as are found in particular in WO-A96/03367 and in the WO-A 96/03479 are described. These reaction products are generally mixtures of pure nitropolyisobutenes (e.g. α , β -dinitropolyisobutene) and mixed hydroxynitropolyisobutenes (e.g. α -nitro- β -hydroxypolyisobutene).

Additives containing hydroxyl groups in combination with mono- or polyamino groups (Dc) are, in particular, reaction products of polyisobutene epoxides obtainable from polyisobutene, preferably having predominantly terminal double bonds, with M _n =300 to 5000, with ammonia, mono- or polyamines, as they are used in particular in EP-A 476 485 are described.

Additives containing carboxyl groups or their alkali metal or alkaline earth metal salts (Dd) are preferably copolymers of C ₂ - to C ₄₀ -olefins with maleic anhydride having a total molecular weight of 500 to 20,000, all or part of the carboxyl groups to the alkali metal or alkaline earth metal salts and one remaining Rest of the carboxyl groups are reacted with alcohols or amines. Such additives are in particular from EP-A 307 815 known. Such additives are mainly used to prevent valve seat wear and, as in the WO-A 87/01126 described, with advantage in combination with customary fuel detergents such as poly(iso)buteneamines or polyetheramines are used.

Additives containing sulfonic acid groups or their alkali metal or alkaline earth metal salts (De) are preferably alkali metal or alkaline earth metal salts of an alkyl sulfosuccinate, as is found in particular in EP-A 639 632 is described. Such additives serve mainly to prevent valve seat wear and can be used to advantage in combination with conventional fuel detergents such as poly(iso)buteneamines or polyetheramines.

Additives containing polyoxy-C ₂ -C ₄ -alkylene groups (Df) are preferably polyethers or polyetheramines, which are obtained by reacting C ₂ - to C ₆₀ -alkanols, C ₆ - to C ₃₀ -alkanediols, mono- or di-C ₂ - to C ₃₀ -alkylamines, C ₁ - to C ₃₀ -alkylcyclohexanols or C ₁ - to C ₃₀ -alkylphenols with 1 to 30 mol of ethylene oxide and/or propylene oxide and/or butylene oxide per hydroxyl group or amino group and, in the case of the polyetheramines, are obtainable by subsequent reductive amination with ammonia, monoamines or polyamines. Such products are particularly in the EP-A 310 875 , EP-A 356 725 , EP-A 700 985 and US-A 4,877,416 described. In the case of polyethers, such products also have carrier oil properties. Typical examples of these are tridecanol or isotridecanol butoxylates, isononylphenol butoxylates and polyisobutenol butoxylates and propoxylates and the corresponding reaction products with ammonia.

Carboxylic acid ester groups (Dg) containing additives are preferably esters of mono-, di- or tricarboxylic acids with long-chain alkanols or polyols, especially those with a minimum viscosity of 2 mm ² / s at 100 ° C, as in particular in the DE-A 38 38 918 are described. Aliphatic or aromatic acids can be used as mono-, di- or tricarboxylic acids, and long-chain representatives having, for example, 6 to 24 carbon atoms are particularly suitable as ester alcohols or ester polyols. Typical representatives of the esters are adipates, phthalates, isophthalates, terephthalates and trimellitates of isooctanol, isononanol, isodecanol and isotridecanol. Such products also fulfill carrier oil properties.

Additives containing groups with hydroxyl and/or amino and/or amido and/or in particular imido groups (Dh) derived from succinic anhydride are preferably corresponding derivatives of alkyl- or alkenyl-substituted succinic anhydride and in particular the corresponding derivatives of polyisobutenylsuccinic anhydride, which are obtained by reaction of conventional or highly reactive polyisobutene with M _n = preferably 300 to 5000, more preferably 300 to 3000, more preferably 500 to 2500, even more preferably 700 to 2500 and especially 800 to 1500, with maleic anhydride thermally in an ene reaction or via the chlorinated polyisobutene are available. The groups with hydroxyl and/or amino and/or amido and/or imido groups are, for example, carboxylic acid groups, acid amides of monoamines, acid amides of di- or polyamines which have free amine groups in addition to the amide function, and succinic acid derivatives with an acid and an amide function, Carboximides with monoamines, carboximides with di- or polyamines which, in addition to the imide function, also have free amine groups, or diimides which are formed by reacting di- or polyamines with two succinic acid derivatives. Such fuel additives are generally known and are described, for example, in documents (1) and (2). They are preferably the reaction products of alkyl- or alkenyl-substituted succinic acids or derivatives thereof with amines and particularly preferably the reaction products of polyisobutenyl-substituted succinic acids or derivatives thereof with amines. Of particular interest here are reaction products with aliphatic polyamines (polyalkyleneimines), such as in particular ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine and hexaethyleneheptamine, which have an imide structure.

In a preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 2012/004300 , there preferably page 5, line 18 to page 33, line 5, particularly preferably of preparation example 1, which is hereby expressly incorporated by reference into the present disclosure.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds as described in the unpublished international application with the application number PCT/EP2014/061834 and the submission date June 6, 2014 (2014/195464), there preferably page 5, line 21 to page 47, line 34, particularly preferably of preparation examples 1 to 17.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 11/95819 A1 , there preferably page 4, line 5 to page 13, line 26, particularly preferably preparation example 2.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 11/110860 A1 , there preferably page 4, line 7 to page 16, line 26, particularly preferably of preparation examples 8, 9, 11 and 13.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 06/135881 A2 , there preferably page 5, line 14 to page 12, line 14, particularly preferably examples 1 to 4.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 10/132259 A1 , there preferably page 3, line 29 to page 10, line 21, particularly preferably example 3.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 08/060888 A2 , there preferably page 6, line 15 to page 14, line 29, particularly preferably examples 1 to 4.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in GB 2496514A , there preferably paragraphs [00012] to [00039], particularly preferably examples 1 to 3.

In a further preferred embodiment, the compounds according to the invention can be combined with quaternized compounds, as described in WO 2013 070503 A1 , there preferably paragraphs [00011] to [00039], particularly preferably examples 1 to 5.

Additives containing groups (Di) produced by Mannich reaction of substituted phenols with aldehydes and mono- or polyamines are preferably reaction products of polyisobutene-substituted phenols with formaldehyde and mono- or polyamines such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine or dimethylaminopropylamine. The polyisobutenyl substituted phenols can be derived from conventional or highly reactive polyisobutene having M _n = 300 to 5000. Such "polyisobutene Mannich bases" are particularly in the EP-A 831 141 described.

One or more of the detergent additives mentioned can be added to the fuel in such an amount that the dosing rate of these detergent additives is preferably 25 to 2500 ppm by weight, in particular 75 to 1500 ppm by weight, especially 150 to 1000 ppm by weight .-ppm, is.

B2) carrier oils

Carrier oils used can be mineral or synthetic. Suitable mineral carrier oils are fractions obtained during petroleum processing, such as bright stock or base oils with viscosities such as from the class SN 500 to 2000, but also aromatic hydrocarbons, paraffinic hydrocarbons and alkoxyalkanols. A fraction known as "hydrocrack oil" and obtained in the refining of mineral oil (vacuum distillate cut with a boiling range of about 360 to 500° C., obtainable from natural mineral oil which has been catalytically hydrogenated and isomerized and dewaxed under high pressure) can also be used. Mixtures of the mineral carrier oils mentioned above are also suitable.

Examples of suitable synthetic carrier oils are polyolefins (polyalphaolefins or polyinternal olefins), (poly)esters, poly)alkoxylates, polyethers, aliphatic polyetheramines, alkylphenol-started polyethers, alkylphenol-started polyetheramines and carboxylic acid esters of long-chain alkanols.

Examples of suitable polyolefins are olefin polymers with M _n =400 to 1800, primarily based on polybutene or polyisobutene (hydrogenated or non-hydrogenated).

Examples of suitable polyethers or polyetheramines are preferably compounds containing polyoxy-C ₂ - to C ₄ -alkylene groups, which are obtained by reacting C ₂ - to C ₆₀ -alkanols, C ₆ - to C ₃₀ -alkanediols, mono- or di-C ₂ - to C ₃₀ -alkylamines, C ₁ - to C ₃₀ -alkyl-cyclohexanols or C ₁ - to C ₃₀ -alkylphenols with 1 to 30 mol of ethylene oxide and/or propylene oxide and/or butylene oxide per hydroxyl group or amino group and, if the polyetheramines, are obtainable by subsequent reductive amination with ammonia, monoamines or polyamines. Such products are particularly in the EP-A 310 875 , EP-A 356 725 , EP-A 700 985 and the US-A 4,877,416 described. For example, poly-C ₂ - to C ₆ -alkylene oxide amines or functional derivatives thereof can be used as polyetheramines. Typical examples of these are tridecanol or isotridecanol butoxylates, isononylphenol butoxylates and polyisobutenol butoxylates and propoxylates and the corresponding reaction products with ammonia.

Examples of carboxylic acid esters of long-chain alkanols are, in particular, esters of mono-, di-, or tricarboxylic acids with long-chain alkanols or polyols, such as those in particular DE-A 38 38 918 are described. Aliphatic or aromatic acids can be used as mono-, di- or tricarboxylic acids, and long-chain representatives having, for example, 6 to 24 carbon atoms are particularly suitable as ester alcohols or ester polyols. Typical representatives of the esters are adipates, phthalates, isophthalates, terephthalates and trimellitates of isooctanol, isononanol, isodecanol and isotridecanol, e.g. B. di-(n- or isotridecyl)phthalate.

Other suitable carrier oil systems are, for example, in DE-A 38 26 608 , DE-A 41 42 241 , DE-A 43 09 074 , EP-A 452 328 and the EP-A 548 617 described.

Examples of particularly suitable synthetic carrier oils are alcohol-started polyethers having about 5 to 35, preferably about 5 to 30, particularly preferably 10 to 30 and in particular 15 to 30 C ₃ - to C ₆ -alkylene oxide units, z. B. propylene oxide, n-butylene oxide and isobutylene oxide units or mixtures thereof, per alcohol molecule. Non-limiting examples of suitable starter alcohols are long-chain alkanols or phenols substituted with long-chain alkyl, where the long-chain alkyl radical is in particular a straight-chain or branched C ₆ - to C ₁₈ -alkyl radical. Particular examples include tridecanol and nonylphenol. Particularly preferred alcohol-started polyethers are the reaction products (polyetherification products) of monohydric aliphatic C ₆ - to C ₁₈ -alcohols with C ₃ - to C ₆ -alkylene oxides. Examples of monohydric aliphatic C ₆ -C ₁₈ alcohols are hexanol, heptanol, octanol, 2-ethylhexanol, nonyl alcohol, decanol, 3-propylheptanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, octadecanol and their constitutional and positional isomers. The alcohols can be used either in the form of the pure isomers or in the form of technical mixtures. A particularly preferred alcohol is tridecanol. Examples of C ₃ - to C ₆ -alkylene oxides are propylene oxide, such as 1,2-propylene oxide, butylene oxide, such as 1,2-butylene oxide, 2,3-butylene oxide, isobutylene oxide or tetrahydrofuran, pentylene oxide and hexylene oxide. Among these, particular preference is given to C ₃ - to C ₄ -alkylene oxides, ie propylene oxide such as 1,2-propylene oxide and butylene oxide such as 1,2-butylene oxide, 2,3-butylene oxide and isobutylene oxide. Specifically, butylene oxide is used.

Other suitable synthetic carrier oils are alkoxylated alkyl phenols, as in the DE-A 10 102 913 are described.

Particular carrier oils are synthetic carrier oils, with the alcohol-started polyethers described above being particularly preferred.

The carrier oil or the mixture of different carrier oils is added to the fuel in an amount of preferably 1 to 1000 ppm by weight, particularly preferably 10 to 500 ppm by weight and in particular 20 to 100 ppm by weight.

B3) cold flow improvers

In principle, suitable cold flow improvers are all organic compounds which are able to improve the flow behavior of middle distillate fuels or diesel fuels in the cold. Appropriately, they must have sufficient oil solubility. In particular, the cold flow improvers ("middle distillate flow improvers", "MDFI") usually used with middle distillates of fossil origin, ie with conventional mineral diesel fuels, come into consideration for this. However, it is also possible to use organic compounds which, when used in conventional diesel fuels, partially or predominantly have the properties of a wax anti-settling additive ("WASA"). They can also act partly or mainly as nucleators. However, it is also possible to use mixtures of organic compounds which are active as MDFIs and/or active as WASAs and/or active as nucleators.

• (K1) Copolymeren eines C₂- bis C₄₀-Olefins mit wenigstens einem weiteren ethylenisch ungesättigten Monomer;
• (K2) Kammpolymeren;
• (K3) Polyoxyalkylenen;
• (K4) polaren Stickstoffverbindungen;
• (K5) Sulfocarbonsäuren oder Sulfonsäuren oder deren Derivaten; und
• (K6) Poly(meth)acrylsäureestern.

Typically, the cold flow improver is selected from:

• (K1) Copolymers of a C ₂ - to C ₄₀ -olefin with at least one further ethylenically unsaturated monomer;
• (K2) comb polymers;
• (K3) polyoxyalkylenes;
• (K4) polar nitrogen compounds;
• (K5) sulfocarboxylic acids or sulfonic acids or their derivatives; and
• (K6) Poly(meth)acrylic acid esters.

Both mixtures of different representatives from one of the respective classes (K1) to (K6) and mixtures of representatives from different classes (K1) to (K6) can be used.

Suitable C ₂ - to C ₄₀ -olefin monomers for the copolymers of class (K1) are, for example, those having 2 to 20, in particular 2 to 10, carbon atoms and having 1 to 3, preferably having 1 or 2, in particular having a carbon-carbon double bond. In the latter case, the carbon-carbon double bond can be arranged both terminally ( α -olefins) and internally. However, α -olefins are preferred, particularly preferably α -olefins having 2 to 6 carbon atoms, for example propene, 1-butene, 1-pentene, 1-hexene and especially ethylene.

In the case of the copolymers of class (K1), the at least one further ethylenically unsaturated monomer is preferably selected from carboxylic acid alkenyl esters, (meth)acrylic acid esters and other olefins.

If other olefins are also polymerized, these are preferably higher molecular weight than the abovementioned C ₂ - to C ₄₀ -olefin base monomers. If, for example, ethylene or propene is used as the olefin base monomer, C ₁₀ - to C ₄₀ -α -olefins are particularly suitable as further olefins. In most cases, further olefins are only polymerized in if monomers with carboxylic acid ester functions are also used.

Suitable (meth)acrylic esters are, for example, esters of (meth)acrylic acid with C ₁ - to C ₂₀ -alkanols, in particular C ₁ - to C ₁₀ -alkanols, especially with methanol, ethanol, propanol, isopropanol, n-butanol, sec. -Butanol, isobutanol, tert-butanol, pentanol, hexanol, heptanol, octanol, 2-ethylhexanol, nonanol and decanol and structural isomers thereof.

Suitable carboxylic acid alkenyl esters are, for example, C ₂ - to C ₁₄ -alkenyl esters, for example the vinyl and propenyl esters, of carboxylic acids having 2 to 21 carbon atoms, the hydrocarbon radical of which can be linear or branched. Among these, preference is given to the vinyl esters. Among the carboxylic acids with a branched hydrocarbon radical, preference is given to those whose branching is in the α-position to the carboxyl group, the α-carbon atom particularly preferably being tertiary, ie the carboxylic acid being a so-called neocarboxylic acid. However, the hydrocarbyl radical of the carboxylic acid is preferably linear.

Examples of suitable carboxylic acid alkenyl esters are vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl neopentanoate, vinyl hexanoate, vinyl neononanoate, vinyl neodecanoate and the corresponding propenyl esters, preference being given to the vinyl esters. A particularly preferred carboxylic acid alkenyl ester is vinyl acetate; Typical group (K1) copolymers resulting therefrom are the ethylene-vinyl acetate copolymers ("EVA") used most frequently.

Particularly advantageous usable ethylene-vinyl acetate copolymers and their preparation are in WO 99/29748 described.

Also suitable as class (K1) copolymers are those which contain two or more different carboxylic acid alkenyl esters as copolymerized units, these differing in the alkenyl function and/or in the carboxylic acid group. Also suitable are copolymers which, in addition to the alkenyl carboxylic ester(s), contain at least one olefin and/or at least one (meth)acrylic ester as copolymerized units.

Also terpolymers of a C ₂ - to C ₄₀ - α -olefin, a C ₁ - to C ₂₀ -alkyl ester of an ethylenically unsaturated monocarboxylic acid having 3 to 15 carbon atoms and a C ₂ - to C ₁₄ -alkenyl ester of a saturated monocarboxylic acid having 2 to 21 Carbon atoms are suitable as class (K1) copolymers. Such terpolymers are in the WO 2005/054314 described. A typical terpolymer of this type is composed of ethylene, 2-ethylhexyl acrylate and vinyl acetate.

The at least one or the other ethylenically unsaturated monomers are present in the copolymers of class (K1) in an amount of preferably 1 to 50% by weight, in particular 10 to 45% by weight and above all 20 to 40% by weight. %, based on the total copolymer, polymerized. The majority by weight of the monomer units in the copolymers of class (K1) thus generally comes from the C ₂ - to C ₄₀ -base olefins.

The class (K1) copolymers preferably have a number-average molecular weight M _n of from 1000 to 20,000, particularly preferably from 1000 to 10,000 and in particular from 1000 to 8000.

Typical comb polymers of component (K2) are, for example, by the copolymerization of maleic anhydride or fumaric acid with another ethylenically unsaturated monomer, for example with an α -olefin or an unsaturated ester such as vinyl acetate, and subsequent esterification of the anhydride or acid function with an alcohol with at least 10 carbon atoms available. Other suitable comb polymers are copolymers of α -olefins and esterified comonomers, for example esterified copolymers of styrene and maleic anhydride or esterified copolymers of styrene and fumaric acid. Suitable comb polymers can also be polyfumarates or polymaleates. In addition, homo- and copolymers of vinyl ethers are suitable comb polymers. As a component of class (K2) suitable comb polymers are, for example, those in the WO 2004/035715 and in " Comb-Like Polymers. Structure and Properties", NA Platé and VP Shibaev, J. Poly. Sci. Macromolecular Revs. 8, pp. 117-253 (1974 )" are described. Mixtures of comb polymers are also suitable.

Polyoxyalkylenes suitable as a component of class (K3) are, for example, polyoxyalkylene esters, polyoxyalkylene ethers, mixed polyoxyalkylene ester ethers and mixtures thereof. These polyoxyalkylene compounds preferably contain at least one, preferably at least two, linear alkyl groups each having 10 to 30 carbon atoms and a polyoxyalkylene group having a number-average molecular weight of up to 5000. Such polyoxyalkylene compounds are, for example, in EP-A 061 895 as well as in the U.S. 4,491,455 described. Particular polyoxyalkylene compounds are based on polyethylene glycols and polypropylene glycols having a number-average molecular weight of 100 to 5000. Polyoxyalkylene mono- and diesters of fatty acids having 10 to 30 carbon atoms, such as stearic acid or behenic acid, are also suitable.

Polar nitrogen compounds suitable as a component of class (K4) can be both ionic and nonionic in nature and preferably have at least one, in particular at least two, substituents in the form of a tertiary nitrogen atom of the general formula >NR ⁷ , where R ⁷ is a C ₈ - bis C ₄₀ hydrocarbon residue. The nitrogen substituents can also be quaternized, ie in cationic form. Examples of such nitrogen compounds are ammonium salts and/or amides, which are obtained by reacting at least one amine substituted with at least one hydrocarbon radical with a carboxylic acid having 1 to 4 carboxyl groups or with a suitable derivative of which are available. The amines preferably contain at least one linear C ₈ - to C ₄₀ -alkyl radical. Primary amines suitable for the preparation of the polar nitrogen compounds mentioned are, for example, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tetradecylamine and the higher linear homologues; secondary amines suitable for this purpose are, for example, dioctadecylamine and methylbehenylamine. Amine mixtures are also suitable for this purpose, in particular amine mixtures which can be obtained industrially, such as fatty amines or hydrogenated tallamines, as described, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 6th edition, in the "Amines, aliphatic" chapter. Examples of acids suitable for the reaction are cyclohexane-1,2-dicarboxylic acid, cyclohexene-1,2-dicarboxylic acid, cyclopentane-1,2-dicarboxylic acid, naphthalenedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid and succinic acids substituted with long-chain hydrocarbon radicals.

In particular, the component of class (K4) is an oil-soluble reaction product of poly(C ₂ - to C ₂₀ -carboxylic acids) having at least one tertiary amino group with primary or secondary amines. The poly(C ₂ -C ₂₀ -carboxylic acids) containing at least one tertiary amino group and on which this reaction product is based preferably contain at least 3 carboxyl groups, in particular 3 to 12, in particular 3 to 5 carboxyl groups. The carboxylic acid units in the polycarboxylic acids preferably have 2 to 10 carbon atoms, in particular they are acetic acid units. The carboxylic acid units are linked in a suitable manner to form the polycarboxylic acids, usually via one or more carbon and/or nitrogen atoms. They are preferably attached to tertiary nitrogen atoms which, in the case of several nitrogen atoms, are connected via hydrocarbon chains.

The component of class (K4) is preferably an oil-soluble reaction product based on poly(C ₂ - to C ₂₀ -carboxylic acids) having at least one tertiary amino group and having the general formula Ila or IIb

darstellt und die Variable B eine C₁- bis C₁₉-Alkylengruppe bezeichnet. Die Verbindungen der allgemeinen Formel Ila und Ilb weisen insbesondere die Eigenschaften eines WASA auf.in which the variable A is a straight-chain or branched C ₂ - to C ₆ -alkylene group or the grouping of the formula III

and the variable B denotes a C ₁ to C ₁₉ alkylene group. The compounds of the general formulas Ila and IIb have, in particular, the properties of a WASA.

Furthermore, the preferred oil-soluble reaction product of component (K4), in particular that of the general formula IIa or IIb, is an amide, an amide-ammonium salt or an ammonium salt in which none, one or more carboxylic acid groups have been converted into amide groups.

Straight-chain or branched C ₂ - to C ₆ -alkylene groups of the variable A are, for example, 1,1-ethylene, 1,2-propylene, 1,3-propylene, 1,2-butylene, 1,3-butylene, 1,4- butylene, 2-methyl-1,3-propylene, 1,5-pentylene, 2-methyl-1,4-butylene, 2,2-dimethyl-1,3-propylene, 1,6-hexylene (hexamethylene) and especially 1,2-ethylene. The variable A preferably comprises 2 to 4, in particular 2 or 3, carbon atoms.

C ₁ - to C ₁₉ -Alkylene groups of the variable B are, for example, 1,2-ethylene, 1,3-propylene, 1,4-butylene, hexamethylene, octamethylene, decamethylene, dodecamethylene, tetradecamethylene, hexadecamethylene, octadecamethylene, nonadecamethylene and especially methylene . The variable B preferably comprises 1 to 10, in particular 1 to 4, carbon atoms.

The primary and secondary amines as reaction partners for the polycarboxylic acids to form component (K4) are usually monoamines, in particular aliphatic monoamines. These primary and secondary amines can be selected from a large number of amines which carry hydrocarbon radicals, which may be bonded to one another.

These amines on which the oil-soluble reaction products of component (K4) are based are usually secondary amines and have the general formula HN(R ⁸ ) ₂ , in which the two variables R ⁸ are each, independently of one another, straight-chain or branched C ₁₀ - to C ₃₀ -alkyl radicals, in particular C ₁₄ - to C ₂₄ -alkyl radicals. These longer-chain alkyl radicals are preferably straight-chain or only slightly branched. As a rule, the secondary amines mentioned are derived, with regard to their relatively long-chain alkyl radicals, from naturally occurring fatty acids or from their derivatives. The two radicals R ⁸ are preferably the same.

The secondary amines mentioned can be bound to the polycarboxylic acids by means of amide structures or in the form of the ammonium salts; it is also possible for only a part to be present as amide structures and another part as ammonium salts. Preferably there are few or no free acid groups present. The oil-soluble reaction products of component (K4) are preferably present entirely in the form of the amide structures.

Typical examples of such components (K4) are reaction products of nitrilotriacetic acid, ethylenediaminetetraacetic acid or propylene-1,2-diaminetetraacetic acid with in each case 0.5 to 1.5 mol per carboxyl group, in particular 0.8 to 1.2 mol per carboxyl group, diolylamine, dipalmitinamine, dicoconut fatty amine, distearylamine, dibehenylamine or in particular ditallow fatty amine. A particularly preferred component (K4) is the reaction product of 1 mole of ethylenediaminetetraacetic acid and 4 moles of hydrogenated ditallow fatty amine.

Other typical examples of component (K4) are the N,N-dialkylammonium salts of 2-N',N'-dialkylamidobenzoates, for example the reaction product of 1 mole of phthalic anhydride and 2 moles of ditallow fatty amine, the latter being hydrogenated or not and the reaction product of 1 mole of an alkenylspirobislactone with 2 moles of a dialkylamine, for example ditallow fatty amine and/or tallow fatty amine, the latter two being hydrogenated or non-hydrogenated.

Other typical structure types for the component of class (K4) are cyclic compounds with tertiary amino groups or condensates of long-chain primary or secondary amines with carboxylic acid-containing polymers, as in the WO 93/18115 are described. Sulfocarboxylic acids, sulfonic acids or their derivatives suitable as cold flow improvers for the component of class (K5) are, for example, the oil-soluble carboxamides and carboxylic acid esters of ortho-sulfobenzoic acid in which the sulfonic acid function is present as a sulfonate with alkyl-substituted ammonium cations, as in EP-A 261 957 to be discribed.

Poly(meth)acrylic acid esters suitable as cold flow improvers of the component of class (K6) are both homo- and copolymers of acrylic and methacrylic acid esters. Copolymers of at least two different (meth)acrylic acid esters which differ in terms of the alcohol condensed in are preferred. If appropriate, the copolymer also contains another, different, olefinically unsaturated monomer as copolymerized units. The weight average molecular weight of the polymer is preferably 50,000 to 500,000. A particularly preferred polymer is a copolymer of methacrylic acid and methacrylic acid esters of saturated _C14 and _C15 alcohols, the acid groups being neutralized with hydrogenated tallamine. Suitable poly (meth) acrylic acid esters are for example in WO 00/44857 described.

The cold flow improver or the mixture of different cold flow improvers is added to the middle distillate fuel or diesel fuel in a total amount of preferably 10 to 5000 ppm by weight, particularly preferably 20 to 2000 ppm by weight, more preferably 50 to 1000 ppm by weight and especially from 100 to 700 wppm, for example from 200 to 500 wppm.

B4) Lubricity improvers

Suitable lubricity improvers (lubricity improvers or friction modifiers) are usually based on fatty acids or fatty acid esters. Typical examples are tall oil fatty acid, such as in WO 98/004656 described, and glycerol monooleate. Also the one in the U.S. 6,743,266 B2 described reaction products from natural or synthetic Oils, e.g. triglycerides, and alkanolamines are suitable as such lubricity improvers.

B5) Corrosion inhibitors other than the described copolymer

Suitable corrosion inhibitors are, for example, succinic esters, ^especially with polyols, fatty acid derivatives, e.g (Ethyl Corporation).

B6) demulsifiers

Examples of suitable demulsifiers are the alkali metal or alkaline earth metal salts of alkyl-substituted phenol and naphthalene sulfonates and the alkali metal or alkaline earth metal salts of fatty acids, as well as neutral compounds such as alcohol alkoxylates, e.g. alcohol ethoxylates, phenol alkoxylates, e.g. tert-butylphenol ethoxylate or tert-pentylphenol ethoxylate, fatty acids, Alkyl phenols, condensation products of ethylene oxide (EO) and propylene oxide (PO), e.g. also in the form of EO/PO block copolymers, polyethylene imines or polysiloxanes.

B7) Dehazer

Suitable dehazers are, for example, alkoxylated phenol-formaldehyde condensates, such as the products available under the trade names NALCO 7D07 (Nalco) and TOLAD 2683 (Petrolite).

B8) Antifoams

Suitable antifoams are, for example, polyether-modified polysiloxanes, such as the products available under the trade names TEGOPREN 5851 (Goldschmidt), Q 25907 (Dow Corning) and RHODOSIL (Rhone Poulenc).

B9) Cetane improver

Suitable cetane improvers include aliphatic nitrates such as 2-ethylhexyl nitrate and cyclohexyl nitrate, and peroxides such as di-tert-butyl peroxide.

B10) Antioxidants

Examples of suitable antioxidants are substituted phenols such as 2,6-di-tert-butylphenol and 6-di-tert-butyl-3-methylphenol and phenylenediamines such as N,N'-di-sec-butyl-p-phenylenediamine.

B11) metal deactivators

Suitable metal deactivators include salicylic acid derivatives such as N,N'-disalicylidene-1,2-propanediamine.

B12) solvents

Suitable are, for example, non-polar organic solvents such as aromatic and aliphatic hydrocarbons, for example toluene, xylenes, "white spirit" and products sold under the trade names SHELLSOL (Royal Dutch/Shell Group) and EXXSOL (ExxonMobil), as well as polar organic solvents -for example alcohols such as 2-ethylhexanol, decanol and isotridecanol. Such solvents usually get into the diesel fuel together with the aforementioned additives and co-additives, which they are supposed to dissolve or dilute for better handling.

C) fuels

The additive according to the invention is outstandingly suitable as a fuel additive and can in principle be used in any fuel. It brings about a whole range of beneficial effects when operating internal combustion engines with fuels. The quaternized additive according to the invention is preferably used in middle distillate fuels, in particular diesel fuels.

The present invention therefore also relates to fuels, in particular middle distillate fuels, with an effective content as an additive to achieve advantageous effects in the operation of internal combustion engines, for example diesel engines, in particular direct-injection diesel engines, especially diesel engines with common-rail injection systems on the quaternized additive according to the invention. This effective content (dosage rate) is generally from 10 to 5000 ppm by weight, preferably from 20 to 1500 ppm by weight, in particular from 25 to 1000 ppm by weight, in particular from 30 to 750 ppm by weight. in each case based on the total amount of fuel.

In principle, the use according to the invention relates to any fuel, preferably diesel and Otto fuels.

Middle distillate fuels such as diesel fuels or heating oils are preferably petroleum raffinates which usually have a boiling range of 100 to 400.degree. These are mostly distillates with a 95% point up to 360°C or even higher. However, this can also be so-called "ultra low sulfur diesel" or "city diesel", characterized by a 95% point of, for example, a maximum of 345° C. and a maximum sulfur content of 0.005% by weight or by a 95% point of for example 285° C. and a maximum sulfur content of 0.001% by weight. In addition to the mineral middle distillate fuels or diesel fuels available through refining, there are also those that are produced by coal gasification or gas liquefaction [“gas to liquid” (GTL) fuels] or by Biomass to liquid (BTL) fuels are available. Mixtures of the aforementioned middle distillate fuels or diesel fuels with regenerative fuels such as biodiesel or bioethanol are also suitable.

The qualities of heating oils and diesel fuels are specified in more detail, for example, in DIN 51603 and EN 590 (cf. also Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, volume A12, p. 617 et seq.).

The use according to the invention in middle distillate fuels of fossil, vegetable or animal origin, which are essentially hydrocarbon mixtures, also relates to mixtures of such middle distillates with biofuel oils (biodiesel). Such mixtures are encompassed by the term "middle distillate fuel". They are commercially available and usually contain the biofuel oils in minor amounts, typically in amounts of 1 to 30% by weight, in particular 3 to 10% by weight, based on the total amount of middle distillate of fossil, vegetable or animal origin and biofuel oil.

Biofuel oils are typically based on fatty acid esters, preferably essentially on alkyl esters, of fatty acids derived from vegetable and/or animal oils and/or fats. Alkyl esters are usually understood to mean lower alkyl esters, in particular _{C.sub.1 -C.sub.4} -alkyl esters, which are obtained by transesterification of the glycerides occurring in vegetable and/or animal oils and/or fats, in particular triglycerides, using lower alcohols, for example ethanol or, above all, methanol ("FAME"), are available. Typical lower alkyl esters based on vegetable and/or animal oils and/or fats that are used as biofuel oil or components thereof are, for example, sunflower methyl ester, palm oil methyl ester ("PME"), soybean oil methyl ester ("SME") and in particular rapeseed oil methyl ester ("RME") .

The middle distillate fuels or diesel fuels are particularly preferably those with a low sulfur content, ie with a sulfur content of less than 0.05% by weight, preferably less than 0.02% by weight, in particular less than 0.005% by weight and especially less than 0.001% by weight sulphur.

All commercially available petrol compositions can be used as petrol. The standard Eurosuper base fuel according to EN 228 should be mentioned here as a typical representative. Furthermore, gasoline compositions are also in accordance with the specification WO 00/47698 possible areas of application for the present invention.

The quaternized additive according to the invention is particularly suitable as a fuel additive in fuel compositions, in particular in diesel fuels, for overcoming the problems described at the outset in direct-injection diesel engines, especially in those with common-rail injection systems.

The invention will now be described in more detail using the following exemplary embodiments. In particular, the test methods mentioned below are part of the general disclosure of the application and are not limited to the specific exemplary embodiments.

Experimental part: A. Analytics GPC analytics

Unless otherwise stated, the mass average Mw and number average molecular weight Mn of the copolymers were measured by gel permeation chromatography (GPC). GPC separation was carried out using two PLge Mixed B columns (Agilent) in tetrahydrofuran at 35° C. Calibration was carried out using a narrow-distribution polystyrene standard (PSS, Germany) with a molecular weight of 162-50400 Da. Hexylbenzene was used as a low molecular weight marker.

B. Manufacturing Examples Synthesis Example 1

• Initial charge: 131.43 g C20-C24 olefin and 154.29 g ^Solvesso® 150
• Feed 1: 43.50 maleic anhydride (heated at 80° C.)
• Feed 2: 25.08 g lauryl acrylate
• Feed 3: 2.31 g of ditert. Butyl peroxide dissolved in 13.07 g of Solvesso ^® 150

The template is heated up to 150° C in a 1 liter pilot plant stirrer.

Feeds 1, 2 and 3 are metered in over the course of 3 hours, and polymerization is then continued for 1 hour.

131.43 g of C20-C24 olefin and 154.29 g ^of Solvesso® 150 were placed in a reactor (1 liter pilot plant stirrer). The mixture was heated to 150°C under a stream of nitrogen and with stirring. 2.31 g of di-tert were added to this over the course of 3 hours. Butyl peroxide dissolved in 13.07 g of ^Solvesso® 150, molten maleic anhydride (43.50 g maleic anhydride, heated at 80° C.) and 25.08 g lauryl acrylate. The reaction mixture was stirred at 150°C for a further hour and then cooled.

The product has a solids content of 54.3% (measured after 2 hours under vacuum at 100° C.).

110.50 g of the product produced in this way were mixed with 2.63 g of water and stirred at 95° C. for 3 hours. Then the unreacted water was distilled off.

The solids content of the hydrolyzed product is 62.7% (measured after 2 hours under vacuum at 100° C.).

C. Application examples Application example 1: DW10 Na soap IDID test (clean-up)

To investigate the influence of the additives on the performance of direct injection diesel engines, the IDID engine test was used as a further test method, in which the exhaust gas temperatures of the cylinders at the cylinder outlet were determined during a cold start of the DW10 engine. A direct-injection diesel engine with a common-rail system from the manufacturer Peugeot was used in accordance with test methods CEC F-098-08. A commercially available B7 diesel fuel in accordance with EN 590 from Aral was used as the fuel. To artificially stimulate the formation of deposits, 1 ppm by weight of sodium naphthenate and 20 ppm by weight of dodecenylsuccinic acid were added to this.

Similar to the CEC F-98 -08 procedure, engine power is measured during the test. The test consisted of two parts:

I. Dirty up:

The test was carried out without the addition of compounds according to this invention. The test was shortened to 8 hours, the CEC F-98 -08 procedure was carried out without the addition of Zn but with the addition of sodium naphthenate and dodecenylsuccinic acid. If significant deviations in exhaust gas temperatures were observed, the test was stopped before reaching the 8 hour mark to avoid engine damage. After the dirty up run, the engine was allowed to cool and then restarted and idled for 5 minutes. During these 5 minutes the engine was warmed up. The exhaust gas temperature from each cylinder was recorded. The lower the differences between the determined exhaust gas temperatures, the lower the amount of IDID formed.

The exhaust gas temperatures of the 4 cylinders ("Z1" to "Z4") were measured at the cylinder outlets after 0 minutes ("ϑ0") and after 5 minutes ("ϑ5"). The results of the exhaust gas temperature measurements with average values ("Δ") and the largest deviations from Δ down ("-") and up ("+") for the two test runs are summarized in the following overview.

II. Clean up:

The test was shortened to 8 hours, the CEC F-98 -08 procedure was performed without the addition of Zn. However, 1 ppm by weight of sodium naphthenate and 20 ppm by weight of dodecenylsuccinic acid and a compound according to the invention in an amount of 40 mg/kg were each added, and the engine output was determined.

After the clean up, the engine was cooled down and restarted. The exhaust gas temperature from each cylinder was recorded. The lower the differences between the determined exhaust gas temperatures, the lower the amount of IDID formed.

The exhaust gas temperatures of the 4 cylinders ("Z1" to "Z4") were measured at the cylinder outlets after 0 minutes ("ϑ0") and after 5 minutes ("ϑ5"). The results of the exhaust gas temperature measurements with average values ("Δ") and the largest deviations from Δ below ("-") and above ("+") are summarized in the following overview.

The following results were determined:

Dirty up clean up - sequence 1:

• ϑ0 Z1: 37° C Z2: 42° C Z3: 21° C Z4: 38° C
• ϑ5 Z1: 97° C Z2: 103° CZ3: 53° C Z4: 27° C
• Δ: 70° C (+33° C / -43° C)

After dirty up:

• ϑ0 Z1: 37°C Z2: 42°C Z3: 21°C Z4: 38°C
• ϑ5 Z1: 97°C Z2: 103°C Z3: 53°C Z4: 27°C
• Δ: 70°C (+33°C / -43°C)

Significant deviations from the mean and significant differences between the individual cylinders prove the presence of IDID.

Clean up:

• ϑ0 Z1: 33° C Z2: 38° C Z3: 36° C Z4: 39° C
• ϑ5 Z1: 52° C Z2: 68° C Z3: 71° C Z4: 79° C
• Δ: 67,5° C (+11,5° C / -15,5° C)

After clean up with 40 ppm additive from synthesis example 1 in the presence of 1 ppm Na+20 ppm dodecenylsuccinic acid:

• ϑ0 Z1: 33°C Z2: 38°C Z3: 36°C Z4: 39°C
• ϑ5 Z1: 52°C Z2: 68°C Z3: 71°C Z4: 79°C
• Δ: 67.5°C (+11.5°C / -15.5°C)

The deviation from the mean temperature of the exhaust gases is low, which speaks for the removal of IDID.

Thus, the compounds according to the present invention are very effective for prevention/removal in direct injection engines, as seen on the Peugeot DW10 engine in a test similar to CEC F-98-08, but with 1 wppm Na in the form of sodium naphthenate and 20 ppm by weight of dodecenylsuccinic acid.

III. DW10 Na power loss test (keep clean)

To study the efficacy of the compounds of the invention against power loss caused by metals such as sodium, potassium and others, the above prescription from the IDID engine test was used.

Instead of a dirty up and clean up sequence, only a keep clean test with 1 ppm sodium naphthenate, 20 ppm dodecenylsuccinic acid and 40 mg/kg of the compound from Synthesis Example 1 was carried out.

The performance measurement was performed according to CEC F-98-08. At the end of an eight-hour test run, no loss of power was noted, the engine's power was 0.4% higher than at the start of the test.

In a comparative example, an analogous test run was carried out without the presence of a compound according to the invention. At the end of an 8-hour test run, a 6.0% drop in power was noted.

Claims (11)

1. The use of copolymers obtainable by

   - in a first reaction step (I) copolymerizing

   (A) at least one ethylenically unsaturated mono- or dicarboxylic acid or derivatives thereof, preferably a dicarboxylic acid or derivatives thereof, more preferably the anhydride of a dicarboxylic acid,

   (B) at least one α-olefin having from at least 12 up to and including 30 carbon atoms,

   (C) optionally at least one further aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different than (B) and

   (D) at least one (meth)acrylic ester of alcohols having at least 5 carbon atoms,

   where component (A) used is maleic anhydride,

   where the molar incorporation ratio in the copolymer of (A)/((B) and (C)) (in total) is from 10:1 to 1:10 and

   where the proportion of one or more of the (meth)acrylic esters (D) based on the amount of monomers (A), (B) and optionally (C) (in total) is 5 to 200 mol%,

   followed by

   - in a second reaction step (II) partly or fully hydrolyzing the anhydride functionalities present in the copolymer obtained from (I) and/or partly hydrolyzing carboxylic ester functionalities present in the copolymer obtained from (I), where at least 10% of the anhydride functionalities are hydrolyzed, and

   where the copolymer obtained from reaction step (II) has a number-average molecular weight Mn of 0.5 to 10 kDa,

   for removing and/or preventing deposits in the fuel system and/or injection system of direct injection diesel and/or gasoline engines.
2. The use of the copolymers as described in claim 1 as an additive for reducing the fuel consumption of direct injection diesel engines, especially of diesel engines with common rail injection systems.
3. The use of the copolymers as described in claim 1 as an additive for minimizing power loss in direct injection diesel engines, especially in diesel engines with common rail injection systems.
4. The use according to claim 3 as an additive for minimizing power loss caused by K, Zn, Ca and/or Na ions (called K, Zn, Ca and Na power loss respectively).
5. The use of the copolymers as described in claim 1 as a gasoline fuel additive for reducing the level of deposits in the intake system of a gasoline engine, such as, more particularly, DISI and PFI (port fuel injector) engines.
6. The use according to claim 1 as a diesel fuel additive for reducing and/or preventing deposits in the fuel systems, especially the injection systems, such as, more particularly, the internal diesel injector deposits (IDIDs), and/or valve sticking in direct injection diesel engines, especially in common rail injection systems.
7. The use according to claim 6 as a diesel fuel additive for reducing and/or preventing the internal diesel injector deposits (IDIDs) caused by Na, Ca and/or K ions (called Na, Ca and K soap IDIDs respectively).
8. The use according to claim 6 as a diesel fuel additive for reducing and/or preventing the internal diesel injector deposits (IDIDs) caused by polymeric deposits.
9. The use according to any of the preceding claims, wherein the fuel is selected from diesel fuels, biodiesel fuels, gasoline fuels, and alkanol-containing gasoline fuels.
10. An additive concentrate comprising, in combination with further diesel or gasoline fuel additives or lubricant additives, at least one copolymer obtainable by

    - in a first reaction step (I) copolymerizing

    (A) at least one ethylenically unsaturated mono- or dicarboxylic acid or derivatives thereof, preferably a dicarboxylic acid or derivatives thereof, more preferably the anhydride of a dicarboxylic acid,

    (B) at least one α-olefin having from at least 12 up to and including 30 carbon atoms,

    (C) optionally at least one further aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different than (B) and

    (D) at least one (meth)acrylic ester of alcohols having at least 5 carbon atoms,

    where component (A) used is maleic anhydride,

    where the molar incorporation ratio in the copolymer of (A)/((B) and (C)) (in total) is from 10:1 to 1:10 and

    where the proportion of one or more of the (meth)acrylic esters (D) based on the amount of monomers (A), (B) and optionally (C) (in total) is 5 to 200 mol%,

    followed by

    - in a second reaction step (II) partly or fully hydrolyzing the anhydride functionalities present in the copolymer obtained from (I) and/or partly hydrolyzing carboxylic ester functionalities present in the copolymer obtained from (I), where at least 10% of the anhydride functionalities are hydrolyzed, and
    where the copolymer obtained from reaction step (II) has a number-average molecular weight Mn of 0.5 to 10 kDa.
11. A fuel composition, lubricant composition or kerosene composition, especially diesel fuel composition, comprising a copolymer obtainable by

    - in a first reaction step (I) copolymerizing

    (A) at least one ethylenically unsaturated mono- or dicarboxylic acid or derivatives thereof, preferably a dicarboxylic acid or derivatives thereof, more preferably the anhydride of a dicarboxylic acid,

    (B) at least one α-olefin having from at least 12 up to and including 30 carbon atoms,

    (C) optionally at least one further aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different than (B) and

    (D) at least one (meth)acrylic ester of alcohols having at least 5 carbon atoms,

    where component (A) used is maleic anhydride,

    where the molar incorporation ratio in the copolymer of (A)/((B) and (C)) (in total) is from 10:1 to 1:10 and

    where the proportion of one or more of the (meth)acrylic esters (D) based on the amount of monomers (A), (B) and optionally (C) (in total) is 5 to 200 mol%,

    followed by

    - in a second reaction step (II) partly or fully hydrolyzing the anhydride functionalities present in the copolymer obtained from (I) and/or partly hydrolyzing carboxylic ester functionalities present in the copolymer obtained from (I), where at least 10% of the anhydride functionalities are hydrolyzed, and
    where the copolymer obtained from reaction step (II) has a number-average molecular weight Mn of 0.5 to 10 kDa.

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