Nucleating agent based on hyperbranched polymers

0001The invention relates to the production of novel nucleating agents (crystal nucleating agents) based on hyperbranched polymers, and their use in crude oils containing paraffin, fuels, fuels, oils or lubricants.

0002The invention further relates to the use of these nucleating agents on fatty fuels such as fatty acid methyl esters.

0003When paraffin-containing fuels, fuels or oils are stored at a lower temperature, solid paraffins are excreted. The temperature at which the first precipitated crystals become visible as turbidity is called the cloud point. As it cools down further, the liquid solidifies more and more through the paraffin crystallization until the pour point is reached.

0004The reason for this solidification lies in the crystallization behavior of the precipitating paraffins. When it solidifies, a three-dimensional network of needles or leaflets is formed, which includes large amounts of liquid. In practice, this leads to pump failure and filter clogging when pumping liquids.

0005Fat-based fuels, such as, for example, mixtures of fatty acid methyl esters, show a similar disadvantageous behavior on cooling as is known from paraffin-containing fuels. For example, when cooling biodiesel based on rapeseed oil, a crystal network of methyl palmitate and methyl stearate crystallites forms, which can lead to filter clogging in the supply system to the combustion units.

0006A number of methods have become known in order to improve the unfavorable cold behavior described:

0007The dewaxing of fuels, fuels or oils can take place by selective adsorption on molecular sieves, by separation as urea inclusion compounds, by solvent extraction or by separation by means of fractional crystallization. In the case of fat-based fuels, it is possible to separate fatty acid methyl esters which are poorly soluble in the cold by means of fractional crystallization, which is referred to as "winterization".

0008To improve the disadvantageous cold behavior, so-called pour point depressants (PPD, pour point depressant) and anti-settling agents (WASA, Wax Anti Settling Additive) are added to the paraffin-containing fuels, fuels, oils and the fat-based fuels.

0009Pour point improvers modify crystal growth by attaching them to the fastest growing areas of the wax crystals. The outer shape of the growing crystals changes from needle or leaflet-shaped to spherical. As a result, the cold flow properties of the additive products improve because no crystal network can form.

0010Anti-settling agents are often surfactant dispersants that attach to crystals of paraffin or fatty acid methyl ester and prevent their agglomeration by electrostatic or steric repulsion. This prevents the disadvantageous sedimentation of the paraffin crystals which precipitate out on cooling.

0011In contrast to these additives, which are usually added, the targeted use of nucleating agents to improve the cold properties has not hitherto been used because reliable, inexpensive additives have not become known.

State of the art

0012It is already known that dendritic polymers with a hydrophobic outer shell can serve as nucleating agents in the production of polymeric foams ("small cell foams"). For example, US Pat. No. 5,393,795 teaches that the nucleating agents claimed there can promote the formation of uniformly small gas bubbles in the production of foams.

0013US Pat. No. 5,418,301 describes the production of hyperbranched polyesters which are esterified at the end with fatty acids and are suitable as constituents of coating resins or lubricants. However, the patent does not refer to the use of such polyesters as nucleating agents.

0014Furthermore, the teaching of US Pat. No. 5,906,970 teaches that dendrimers based on polyamidoamines are suitable in principle as flow improvers for fossil and fat-derived fuels. It is disadvantageous that the dendrimers described in the patent are only accessible through very complex, multi-stage synthesis and therefore have not been used in technology to date.

Task and solution of the task

0015The object was therefore to provide nucleating agents which can improve the cold flow behavior in low concentrations in paraffin-containing crude oils, fuels, fuels, oils or lubricants and which can be easily optimized for the respective matrix. Another object was to provide nucleating agents which can improve the cold flow behavior in low-concentration fuels and fuels even at low concentrations and which can be easily optimized for differently composed fat-based fuels.

0016This object is achieved by hyperbranched polymers as nucleating agents of the formula (I)<maths id="math0001" num=""><img file="EP1557441A2_D0001.tif" /></maths> according to claim 1, wherein n or m independently of one another 0, 1 or n + m &lt;k, and k can be 10 to 500 R represents the same or different unbranched, saturated alkyl radicals having 8 to 40 carbon atoms, M1 is an identical or different organic, solubilizing group with 10 to 1000 carbon atoms, M2 is an identical or different organic, dispersing radical with 10 to 100 carbon atoms, which contains at least one N atom and which can be uncharged or zwitterionic L1, L2 and L3 each have the same or different divalent ester, carbonate, ether, thioether, amide, urethane, urea or a -C (O) -CH₂-CH₂-NR 'group is and R 'is an unbranched, saturated alkyl radical having 8 to 40 carbon atoms.

0017These nucleating agents can be used alone or in combination with known pour point improvers and / or anti-settling agents in paraffin-containing crude oils, fuels, fuels, oils, lubricants or in fat-based fuels in a concentration range from 0.005 to 5 percent by weight, preferably from 0.01 to 2 percent by weight, particularly preferably from 0 , 05 - 1 percent by weight can be added.

Working principle

0018The following models are intended to explain the inventive idea without restricting it.

0019Curved molecular surfaces that carry paraffinic end groups can incorporate and attach other unbranched paraffins. This creates spontaneous crystalline areas where further crystal growth can occur. In contrast to homogeneous nucleation, which is inhibited by the contribution of the surface energy, each addition of a paraffin molecule is energetically advantageous here.

0020A model presentation of this induced homogeneous nucleation is shown in FIG. 1.

0021-L- stands for a divalent group that links the hyperbranched polymer core to a terminal alkyl group.

0022According to this model, the nucleating agents according to the invention can be regarded as homogeneously dissolved nano-crystal nuclei.

0023As the temperature drops, the relative oversaturation of the paraffins in paraffin-containing fuels, fuels, oils or lubricants increases. Addition of the nucleating agents according to the invention results in the advantageous formation of many small crystallites, even in the case of low supersaturation, the growth form of which may be influenced further by adding known polymeric crystal modifiers.

0024Surprisingly, it was found that the nucleating agents according to the invention are also effective in fatty fuels, in particular in fatty acid methyl esters. Obviously, fatty acid methyl ester chains, similar to paraffin chains, can also induce crystallization on the outside of the nucleating agents.

0025The nucleation effect in paraffin-containing crude oils, fuels, fuels, oils, lubricants or in fat-derived fuels can be optimized, for example, by the radius of curvature of the hyperbranched polymer core, by targeted variation of the number of external alkyl groups, the chain length of these alkyl groups and the chain length distribution .

0026Furthermore, the solubility and the agglomeration behavior of the nucleating agents can be influenced by the fact that any solubility-imparting residues via a divalent group L₁ and / or residues with a dispersing action via a divalent group L.₂ be bound to the hyperbranched polymer core. Figure 2 shows an example of solubilizing residues. Figure 3 shows an example of dispersing residues.

Preparation of the nucleating agents

0027Hyperbranched polymers are obtained by converting polyfunctional monomers capable of branching into polydisperse polymers in one step under controlled conditions. Depending on the monomers used and the production conditions used, the outer shape of such polymers can be almost spherical or can also take on an ellipsoid, cylindrical, hemispherical or an irregularly curved shape.

0028Hyperbranched polymers and their method of preparation are described, for example, in Hult et al. in "Advances in Polymer Science", pages 1 to 34, volume. 143 (1999), ed. J. Roovers, Springer Verlag New York, or in A. Sunder et al., Advanced Materials, pages 235 to 239, volume 12 (2000).

0029In contrast, dendritic polymers ("dendritic polymers") are produced starting from a polyvalent starting molecule by step-by-step construction using polyfunctional monomers. As a rule, the respective intermediate products are cleaned after each synthesis stage in order to obtain an approximately monodisperse polymer as the end product.

0030Dendritic polymers and their method of preparation are described, for example, in Tomalia et al. "Starburst Dendrimers: Molecular-Level Control of Size, Shape, Surface Chemistry, Topology and Flexibility from Atoms to Macroscopic Matter", Angew. Chem. Int. Ed. Engl., Vol. 29, pages 138 to 175 (1990).

0031The nucleating agents according to the invention are preferably based on hyperbranched polymers, since they can be easily and inexpensively produced in a wide range of variations.

0032The hyperbranched polymers suitable for the preparation of the nucleating agents according to the invention carry 10 to 500, preferably 20 to 300, particularly preferably 30 to 200 identical or different terminal hydroxyl, carboxyl or amino groups, preferably hydroxyl and carboxyl groups.

0033Commercially available hyperbranched polymers are preferably used as the basis for producing the nucleating agents according to the invention. Examples of such polymers are hyperbranched polyglycerols with terminal OH groups and hyperbranched polyethyleneimines with terminal amino groups from Hyperpolymers GmbH, Freiburg (Germany), known as PG-2, PG-5, PG-8, PEI-5, PEI-25 are sold and hyperbranched Polyster with terminal OH groups from Perstorp, Perstorp (Sweden), which are sold under the name Boltom H-20, Boltorn H-30, Boltorn H-40.

0034Furthermore, all hyperbranched polymers which are described in US Pat. No. 5,418,301 are also suitable.

0035To produce the nucleating agents according to the invention, the hyperbranched polymers mentioned are linked to suitable long-chain, terminally functionalized, unbranched alkyl compounds. The resulting link preferably consists of one of the following divalent groups.<chemistry id="chem0001" num="0001"><img file="EP1557441A2_D0002.tif" /></chemistry><chemistry id="chem0002" num="0002"><img file="EP1557441A2_D0003.tif" /></chemistry> where R 'represents a hydrogen radical or an unbranched saturated alkyl radical having 8 to 40 carbon atoms.

0036Ester, amide or urethane groups are preferred as divalent linking groups.

0037For example, to produce a nucleating agent with ester-linked alkyl groups, one of the following combinations of starting products can be reacted with one another:<ul id="ul0001" list-style="none"><li>a) hyperbranched polymer with terminal hydroxyl groups + fatty acids or activated fatty acid derivatives, such as fatty acid chlorides,</li><li>b) hyperbranched polymer with terminal carboxyl groups or terminal acid chloride groups + fatty alcohols.</li></ul>

0038Long-chain compounds suitable for producing the nucleating agents according to the invention are unbranched, saturated fatty acids, fatty alcohols or fatty isocyanates each having 10 to 40 C atoms, preferably each having 14 to 24 C atoms. The activated fatty acid or activated fatty alcohol derivatives derived therefrom are also suitable.

0039Unbranched, saturated primary and secondary fatty amines of the structure HNRR 'are also suitable, where R and R' are identical or different hydrogen or saturated unbranched aliphatic radicals having 10 to 30 C atoms, preferably 14 to 24 C atoms.

0040Examples of preferred fatty acids or fatty acid derivatives are lauric, myristic, palmitic, stearic, arachidic, behenic, cerotinic and melissic acid, as well as mixtures thereof and the acid chlorides, acid anhydrides, methyl esters derived therefrom and mixtures thereof.

0041Examples of preferred fatty alcohols or fatty alcohol derivatives are lauryl, myristyl, palmityl, stearyl, arachidyl, behenyl and cerotyl alcohol as well as mixtures thereof and the chloroformic acid esters derived therefrom.

0042Technical mixtures of essentially unbranched C8-C24 alcohols, such as those obtained as so-called oxo alcohols from oxo processes, are also suitable for the reaction.

0043Examples of preferred primary amines are octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecylamine, aminopropylstearylamine, aminopropyllaurylamine, aminopropyloleylamine and mixtures thereof.

0044Examples of preferred secondary amines are dipalmitinamine, dioleylamine, dicoconut fatty amine, dibehenylamine, in particular ditallow fatty amine, and mixtures thereof.

Manufacturing process / reactions / reaction conditions

0045The esterification of hyperbranched hydroxyl-functionalized polymers with fatty acids or vice versa of hyperbranched carboxyl-functionalized polymers with fatty alcohols can be catalyzed or uncatalyzed, preferably acid-catalyzed by heating with elimination of water at reaction temperatures between 60 to 200 ° C., preferably between 80 to 180 ° C. in the Melt or in a suitable solvent if necessary using an azeotrope.

0046Suitable esterification catalysts are, for example, toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, sulfuric acid, phosphoric acid, boron trifluoride, tin tetrachloride, tetrabutyl orthotitanate, Sn powder or organic tin compounds, such as so-called Fascat catalysts.

0047If the reaction is carried out in a solvent or solvent mixture, the solvent can be removed by evaporation at elevated temperature after the end of the reaction and the remaining melt can be granulated by dripping onto a cooled steel strip.

0048Instead of the free fatty acids, activated fatty acid derivatives such as fatty acid chlorides or fatty acid anhydrides can also be used for the esterification.

0049Detailed information on catalysis and reaction management for esterifications and transesterifications are described in detail in the monograph by J. Otera, Esterification, Wiley-VCH (2003).

0050Nucleating agents with amide-linked alkyl groups can be prepared by reacting an amino-terminated hyperbranched polymer with fatty acids or activated fatty acid derivatives or, conversely, by reacting a carboxyl-terminated hyperbranched polymer with primary or secondary fatty amines. When using an amino-terminated hyperbranched polymer, activated fatty acid derivatives are preferred as the reaction components, the fatty acid methylethers.

0051Such amidations are carried out by heating with elimination of water at reaction temperatures between 80 to 200 ° C., preferably between 80 to 160 ° C. in the melt or in a suitable solvent, optionally using an azeotrope. In the case of hydroxyl- or amino-terminated hyperbranched polymers, alkyl chains can be introduced by a two-stage reaction: in the first step, the corresponding acrylic acid ester or the corresponding acrylamide is prepared in a known manner with water escaping. In a second stage, primary or secondary fatty amines or long-chain alkyl thiols are added to the double bond by means of a Michael addition with or without the use of a solvent in a temperature range between 80 to 140 ° C., preferably between 100 to 120 ° C.

Application modification of the nucleating agents

0052In addition to the alkyl groups essential for the nucleation effect, additional modifying groups can be incorporated in the outer shell of the hyperbranched polymers for further optimization in terms of application technology. The incorporation of the solubilizing or dispersing residues is carried out analogously to the manner already described above when the alkyl residues are introduced.

Solubilizing residues

0053Thus solubility-imparting radicals M1 of formula (I) can be used to further optimize the overall effect of the nucleating agents according to the invention. If, for example, the nucleating agent in a paraffin-containing matrix has insufficient solubility at room temperature, solubility-imparting residues, such as branched polyalkylene, branched and unbranched polyoxalkylene residues, can be introduced via a divalent group L.₁ be linked to the polymer core.

0054Examples of suitable solubilizing compounds are<ul id="ul0002" list-style="dash" compact="compact"><li>Guerbet alcohols made from tallow fatty alcohols,</li><li>Guerbet acids, produced by oxidation from Guerbet alcohols,</li><li>Polytetrahydrofurans blocked on one side with a molecular weight &lt;10000g / mol,</li><li>Branched and / or unsaturated fatty acids, such as 2-ethylhexanoic acid, isostearic acid, oleic acid, elaidic acid, linoleic acid,</li><li>Hydroxyl- or amino-terminated polyisobutenes with a molecular weight of &lt;1000 g / mol.</li></ul>

Residues with a dispersing effect

0055Furthermore, according to formula (I), the hyperbranched polymer core can be linked to residues having a dispersing action. Such dispersing side chains M2, which are bonded to the hyperbranched core via the divalent groups L2, can prevent the agglomeration of the nucleating agent according to the invention and the very small crystallites formed therefrom and thereby prevent settling of the very small crystallites which form.

0056The basic procedure for the production of such modified nucleating agents can be explained using an example: in a first stage, hydroxyl-terminated hyperbranched polymers are converted to nucleating agents by esterification with saturated, unbranched fatty acids. The stoichiometry is adjusted so that free hydroxyl groups are still present. This product is then esterified with an acid anhydride. The resulting free carboxyl function is then converted into a salt by stoichiometric addition of an amine compound.

0057Examples of acid anhydrides which are preferably used for this reaction are maleic anhydride, phthalic anhydride and succinic anhydride.

0058Preferred amines are secondary and tertiary fatty amines, but also cyclic compounds such as morpholine.

Combination with known flow improvers and paraffin dispersants

0059The nucleating agents according to the invention can be used alone or in combination with known pour point depressants.

0060Suitable pour point depressants are copolymers or terpolymers or comb polymers based on ethylene and vinyl esters, polyacrylates or polymethacrylates, examples of such products are:<ul id="ul0003" list-style="dash" compact="compact"><li>Ethylene-vinyl acetate-hexene terpolymers according to DE-A-34 43 475</li><li>Ethylene-vinyl acetate-diisobutylene terpolymers according to EP-A-0 203 554</li><li>Copolymers of ethylene with alkyl carboxylic acid vinyl ester according to EP-A-0 491 225</li><li>Fumarate-vinyl acetate comb polymers according to EP-A-0 153 176</li><li>Comb polymers of a C6-C24-α-olefin and an N-C6 to C22-alkyl maleimide according to EP-A-0 320 766</li></ul>

0061Furthermore, the nucleating agents according to the invention can be used in combination with polar nitrogen-containing monomeric or polymeric paraffin dispersants (anti-settling agents). Examples of such nitrogen-containing paraffin dispersants are:<ul id="ul0004" list-style="dash"><li>Reaction products of alkenyl spirobis lactones with amines according to EP-A-0 413 279,</li><li>Oil-soluble reaction products of phthalic anhydride with amines according to EP-A-0 061 894,</li><li>Reaction products of aminoalkylene carboxylic acids with amines according to EP-A-0 597 278,</li><li>Reaction products of alternating copolymers based on α, β-unsaturated compounds and maleic anhydride with primary amines and aliphatic alcohols according to EP-A-0 154 177,</li><li>Copolymers based on aliphatic olefins and maleic anhydride, the copolymer having ester and amide groups according to EP-A-0 283 293,</li><li>Reaction products of copolymers based on maleic anhydride and α, β-unsaturated compounds such as styrene with dialkylamines according to EP-A-0 436 151,</li><li>Copolymers based on α, β-unsaturated olefins with at least 3 C atoms and α, β-unsaturated dicarboxylic acid anhydrides, the dicarboxylic acid anhydride units being converted into imide, amide and ammonium units by polymer-analogous reaction with polyetheramines or alkanolamines -0 688 796.</li></ul>

Combination with other additives

0062The nucleating agents according to the invention can be used alone or in combination with other additives such as, for example, antioxidants, corrosion protection agents, anti-wear or lubricity additives, dyes or marking agents, antistatic agents, cetane number improvers, demulsifiers, anti-foam agents or metal deactivators.

Use of the compounds according to the invention

0063The nucleating agents according to the invention are used as an additive in paraffin-containing crude oils, fuels, fuels, oils or lubricants and in fat-based fuels, fuels or oils.

0064Examples of middle distillates are refinery products with a boiling range of approx. 150 - 500 ° C, which are available as heating oils, diesel fuel, kerosene, jet fuel.

0065Furthermore, the nucleating agents according to the invention are particularly suitable for hydrocarbon mixtures from technical or semi-technical Fischer-Tropsch processes. Such fuels have become known under the name "Synfuel" or "Sunfuel". Furthermore, the nucleating agents according to the invention can be used with paraffin-containing fuels based on pyrolysis oils. The extraction of such pyrolysis oils is described, for example, in H. Kopetz, T. Weber, W. Palz, P. Chartier, GL Ferrero (ed.), Biomass for Energy and Industry, Proceedings ofthe International Conference Würzburg, Germany 8-11 June 1998.

0066Examples of fatty fuels are fatty acid methyl esters made from rapeseed oil, soybean oil, palm oil, beef tallow, sunflower oil, used cooking fat from catering establishments and mixtures thereof. The nucleating agents according to the invention are likewise very effective in mixtures consisting of middle distillate products with fatty fuels, in particular in mixtures of fatty acid methyl esters with diesel fuel in a mixing ratio of 1:99 to 99: 1.

0067The advantageous effect of the nucleating agents according to the invention is based on the fact that, in the case of the aforementioned products, even with a very slight oversaturation of the precipitating paraffin constituents or the corresponding fatty acid esters, simultaneous crystal growth which covers the entire product matrix begins. The flowability of the products is maintained over a wide temperature range when cooled.

0068Furthermore, the nucleating agents according to the invention can be used as additives (seed crystals) in the production of paraffin waxes from petroleum products, for the dewaxing of lubricating oils or for adjusting the flow properties of lubricating greases.

0069Detailed information on the production of paraffin waxes and dewaxing can be found in M. Freund, Paraffin Products, Elsevier Scientific Publishing Company (1982)

0070The nucleating agents according to the invention are added to paraffin-containing fuels, fuels, oils or lubricants and fat-based fuels and fuels in a concentration range between 0.005-5 weight percent, preferably 0.01-2 weight percent, particularly preferably 0.05-1 weight percent.

0071For easier dosing, liquid or pasty concentrates with up to 70 percent by weight of nucleating agents can be produced. The matrix to be added is advantageously used as the solvent for the production of these concentrates. Other suitable solvents are chlorinated hydrocarbons, such as dichloromethane or chloroform, liquid isoparaffins, aromatics such as toluene, xylene, methylnaphthalene mixtures, high-boiling aromatic mixtures such as solvent naphtha.

0072The temperature during the incorporation of the nucleating agents according to the invention into a matrix is ​​selected so that a homogeneous solution is formed with the matrix. The control of whether the nucleating agent is homogeneously dissolved can be carried out by examination methods which are customary in colloid chemistry, such as, for example, microscopy, light scattering or ultracentrifugation.

0073Suitable incorporation temperatures are 20 to 120 ° C, preferably 30 to 100 ° C, particularly preferably 40 to 80 ° C.

Test methods for testing effectiveness

0074The following test methods were used to assess the effectiveness of the nucleating agents according to the invention:<ul id="ul0005" list-style="none"><li>Test A: Determination of filterability: CFPP value (Cold Filter Plugging Point) determined according to DIN EN 116</li><li>Test B: The additive products were stored in 1000 ml measuring cylinders for 20 hours in a refrigerator at -13 ° C. The volume and appearance of the paraffin phase and the liquid phase were then determined visually.</li></ul>

Examples:

0075The following examples 1 to 8 are each shown graphically in the attached drawing figures 4 to 11.

Example 1 (Additive A)

0076Equipment: 250 mL three-necked flask equipped with an internal thermometer, reflux condenser with Dean-Stark water separator, mechanical stirrer, argon introduction for inerting and heating bath.

0077The following are weighed into the apparatus as reaction components:<ul id="ul0006" list-style="none" compact="compact"><li>22.0 g Boltom H40, hydroxyl terminated hyperbranched polymer</li><li>21.3 g stearic acid</li><li>19.2 g palmitic acid</li><li>50 ml xylene</li><li>0.2 g p-toluenesulfonic acid</li></ul>

0078The reaction mixture was heated to boiling with stirring. A weak stream of argon was passed through the reaction solution and the water of reaction formed was collected. The mixture was heated until a sample showed an acid number &lt;5 mg KOH / g.

0079The solvent was then distilled off (internal temperature 155 ° C.) and the residual melt was freed from residual solvent and volatile components for 30 min at 130 ° C. in a water jet vacuum.

0080The melt was then dripped onto a cold sheet and thereby pastilled. The colorless wax-like product is readily soluble in diesel fuel and biodiesel at room temperature.

Example 2 (Additive B)

0081The experiment from Example 1 was repeated with the following weights:<ul id="ul0007" list-style="none" compact="compact"><li>22.0 g Boltorn H40</li><li>42.6 g stearic acid</li><li>5.6 oleic acid</li><li>0.2 ml methanesulfonic acid as an esterification catalyst</li><li>50 ml xylene</li></ul>

0082The colorless wax-like product is readily soluble in diesel fuel and biodiesel at room temperature.

Example 3 (Additive C)

0083In an apparatus as described in Example 1, 22.0 g of Boltom H40, 42.6 g of stearic acid and 0.2 ml of methanesulfonic acid in 70 ml of toluene were heated with stirring and refluxing for 4 h and the water of reaction was removed. A mixture of 3.6 g of acrylic acid and 0.1 g of methylhydroquinone was then added and the reaction solution was heated with stirring for a further 4 h. In the next step, the solvent and the unreacted acrylic acid were distilled off in a water jet vacuum. The internal temperature should not exceed 120 ° C. 5.2 g of distearylamine were added to the melt and the mixture was stirred at 120 ° C. for 2 h. The melt was then poured onto a cold sheet and the solidified mass was granulated.

Example 4 (Additive D)

0084In an apparatus as described in Example 1, 22.0 g of Boltorn H40, 38.4 g of palmitic acid and 0.1 g of p-toluenesulfonic acid in 50 ml of xylene were heated with stirring and refluxing until a sample had an acid number &lt;5 mg KOH / g showed. The solvent and volatile by-products were then distilled off in a water jet vacuum at 120 ° C. A mixture of 50 ml of diesel fuel, 3 g of stearyl isocyanate and 0.1 g of diazabicyclononane was added to this melt and the mixture was stirred for 3 h. The product mixture obtained was diluted with 1 L of diesel fuel and was a ready-to-use additive solution.

Example 5 (Additive E)

0085In an apparatus as described in Example 1, 18.0 g of Boltorn H40, 3 g of Boltorn H30, 44.0 g of stearic acid and 0.1 g of p-toluenesulfonic acid in 50 ml of xylene were heated with stirring and refluxing until a sample showed an acid number &lt;5 mg KOH / g. The solvent and volatile by-products were then distilled off in a water jet vacuum at 130 ° C. A mixture of 50 ml of old fat methyl ester and 1.5 g of phthalic anhydride was added to this melt and the mixture was stirred at 120 ° C. for 2 h. A mixture of 3.3 g of N, N-dimethyl-stearylamine and 11 diesel fuel was then added to this reaction solution and the mixture was stirred for 10 minutes. The product mixture obtained was a ready-to-use additive solution.

Example 6 (Additive F)

0086In an apparatus as described in Example 1, 22.0 g of Boltom H40, 42.6 g of stearic acid, 0.2 ml of methanesulfonic acid as the esterification catalyst and 60 ml of xylene were heated with stirring and refluxing until a sample had an acid number> 5 mg KOH / g showed. The solvent and volatile by-products were then distilled off in a water jet vacuum at 130 ° C. 5.0 g of polyisobutenyl succinic anhydride (PIBSA, M_n 1000), dissolved in 11 biodiesels and stirred for 10 minutes. The product mixture obtained was a ready-to-use additive solution.

0087The nucleating agents according to the invention were tested in various middle distillates (diesel fuel DKL1, diesel fuel DK2) and fat-derived fuels (fatty acid methyl ester FAME1, made from rapeseed oil, fatty acid methyl ester FAME2, made from used cooking fat), which showed the following properties: <tables id="tabl0001" num="0001"><table frame="all"><tgroup cols="5" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="31.50mm" /><colspec colnum="2" colname="col2" colwidth="31.50mm" /><colspec colnum="3" colname="col3" colwidth="31.50mm" /><colspec colnum="4" colname="col4" colwidth="31.50mm" /><colspec colnum="5" colname="col5" colwidth="31.50mm" /><thead valign="top"><row><entry namest="col1" nameend="col1" /><entry namest="col2" nameend="col2" align="left">method</entry><entry namest="col3" nameend="col3" align="left">unit</entry><entry namest="col4" nameend="col4" align="left">DK1</entry><entry namest="col5" nameend="col5" align="left">DK2</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">CFPP</entry><entry namest="col2" nameend="col2" align="left">DIN EN 116</entry><entry namest="col3" nameend="col3" align="left">° C</entry><entry namest="col4" nameend="col4" align="left">-3</entry><entry namest="col5" nameend="col5" align="left">-4</entry></row><row><entry namest="col1" nameend="col1" align="left">Density at 20 ° C</entry><entry namest="col2" nameend="col2" align="left">EN ISO 12185</entry><entry namest="col3" nameend="col3" align="left">g / ml</entry><entry namest="col4" nameend="col4" align="left">0,822</entry><entry namest="col5" nameend="col5" align="left">0,824</entry></row><row><entry namest="col1" nameend="col1" align="left">Beginning of boiling</entry><entry namest="col2" nameend="col2" align="left">PR EN ISO 3405</entry><entry namest="col3" nameend="col3" align="left">° C</entry><entry namest="col4" nameend="col4" align="left">164</entry><entry namest="col5" nameend="col5" align="left">160</entry></row><row><entry namest="col1" nameend="col1" align="left">20% boiling point</entry><entry namest="col2" nameend="col2" align="left">PR EN ISO 3405</entry><entry namest="col3" nameend="col3" align="left">° C</entry><entry namest="col4" nameend="col4" align="left">210</entry><entry namest="col5" nameend="col5" align="left">205</entry></row><row><entry namest="col1" nameend="col1" align="left">90% boiling point</entry><entry namest="col2" nameend="col2" align="left">PR EN ISO 3405</entry><entry namest="col3" nameend="col3" align="left">° C</entry><entry namest="col4" nameend="col4" align="left">340</entry><entry namest="col5" nameend="col5" align="left">336</entry></row><row><entry namest="col1" nameend="col1" align="left">End of boiling</entry><entry namest="col2" nameend="col2" align="left">PR EN ISO 3405</entry><entry namest="col3" nameend="col3" align="left">° C</entry><entry namest="col4" nameend="col4" align="left">365</entry><entry namest="col5" nameend="col5" align="left">361</entry></row><row><entry namest="col1" nameend="col1" align="left">CFPP</entry><entry namest="col2" nameend="col2" align="left">DIN EN 116</entry><entry namest="col3" nameend="col3" align="left">° C</entry><entry namest="col4" nameend="col4" align="left">-12</entry><entry namest="col5" nameend="col5" align="left">-8</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">Density at 20 ° C</entry><entry namest="col2" nameend="col2" align="left">EN ISO 12185</entry><entry namest="col3" nameend="col3" align="left">g / ml</entry><entry namest="col4" nameend="col4" align="left">0,884</entry><entry namest="col5" nameend="col5" align="left">0,883</entry></row></tbody></tgroup></table></tables>

0088These fuels were tested with the products A - F produced from Examples 1-6 and showed the following results according to Test A and Test B: <tables id="tabl0002" num="0002"><table frame="all"><tgroup cols="6" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="26.25mm" /><colspec colnum="2" colname="col2" colwidth="26.25mm" /><colspec colnum="3" colname="col3" colwidth="26.25mm" /><colspec colnum="4" colname="col4" colwidth="26.25mm" /><colspec colnum="5" colname="col5" colwidth="26.25mm" /><colspec colnum="6" colname="col6" colwidth="26.25mm" /><thead valign="top"><row><entry namest="col1" nameend="col1" /><entry namest="col2" nameend="col2" align="left">product</entry><entry namest="col3" nameend="col3" align="left">Active substance concentration *</entry><entry namest="col4" nameend="col4" align="left">CFPP</entry><entry namest="col5" nameend="col5" align="left">Paraffin phase vol.% / Appearance</entry><entry namest="col6" nameend="col6" align="left">Liquid phase vol.% / Appearance</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">DK1</entry><entry namest="col2" nameend="col2" align="left">A</entry><entry namest="col3" nameend="col3" align="left">500 ppm</entry><entry namest="col4" nameend="col4" align="left">-5</entry><entry namest="col5" nameend="col5" align="left">90%, dispersed</entry><entry namest="col6" nameend="col6" align="left">10%, sure</entry></row><row><entry namest="col1" nameend="col1" align="left">DK2</entry><entry namest="col2" nameend="col2" align="left">D</entry><entry namest="col3" nameend="col3" align="left">500 ppm</entry><entry namest="col4" nameend="col4" align="left">-8</entry><entry namest="col5" nameend="col5" align="left">95%, dispersed</entry><entry namest="col6" nameend="col6" align="left">5%, sure</entry></row><row><entry namest="col1" nameend="col1" align="left">FAME1</entry><entry namest="col2" nameend="col2" align="left">C.</entry><entry namest="col3" nameend="col3" align="left">800 ppm</entry><entry namest="col4" nameend="col4" align="left">-15</entry><entry namest="col5" nameend="col5" align="left">90%, dispersed</entry><entry namest="col6" nameend="col6" align="left">10%, sure</entry></row><row><entry namest="col1" nameend="col1" align="left">FAME2</entry><entry namest="col2" nameend="col2" align="left">B</entry><entry namest="col3" nameend="col3" align="left">800 ppm</entry><entry namest="col4" nameend="col4" align="left">-12</entry><entry namest="col5" nameend="col5" align="left">90%, dispersed</entry><entry namest="col6" nameend="col6" align="left">10%, sure</entry></row><row><entry namest="col1" nameend="col1" align="left">DK1</entry><entry namest="col2" nameend="col2" align="left">E</entry><entry namest="col3" nameend="col3" align="left">600 ppm</entry><entry namest="col4" nameend="col4" align="left">-5</entry><entry namest="col5" nameend="col5" align="left">100% dispersed</entry><entry namest="col6" nameend="col6" align="left">0%, -</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">FAME1</entry><entry namest="col2" nameend="col2" align="left">F</entry><entry namest="col3" nameend="col3" align="left">600 ppm</entry><entry namest="col4" nameend="col4" align="left">-14</entry><entry namest="col5" nameend="col5" align="left">95%, dispersed</entry><entry namest="col6" nameend="col6" align="left">5%, sure</entry></row></tbody></tgroup><tgroup cols="6" colsep="0" rowsep="0"><colspec colnum="1" colname="col1" colwidth="26.25mm" /><colspec colnum="2" colname="col2" colwidth="26.25mm" /><colspec colnum="3" colname="col3" colwidth="26.25mm" /><colspec colnum="4" colname="col4" colwidth="26.25mm" /><colspec colnum="5" colname="col5" colwidth="26.25mm" /><colspec colnum="6" colname="col6" colwidth="26.25mm" /><tbody valign="top"><row><entry namest="col1" nameend="col6" align="justify">* Active ingredient concentration based on the solids content of the sample products</entry></row></tbody></tgroup></table></tables>

0089The examples show that the nucleating agents produced in a very low concentration lower the CFPP value and lead to a well-dispersed, very fine crystal mass.