Use of substituted ureas or urethanes for further improvement of the cold flow properties of mineral oils and crude oils

Abstract

The use of substituted monoureas, diureas, polyureas, monourethanes, bisurethanes or polyurethanes of the formula R 1 X—CO—NR 3 R 4 in which X is R 2 N or O and R 1 to R 4 are each independently hydrogen, alkyl radicals, alkenyl radicals, cycloalkyl radicals, aryl radicals or arylalkyl radicals, where at least one variable must comprise 4 carbon atoms and where the urea or urethane functionality may be replicated via bridging members, for further improvement of the cold flow properties of mineral oils and crude oils which already comprise further organic compounds suitable for dispersion or for promoting dispersion of paraffin crystals which precipitate under cold conditions, and organic compounds which improve the cold flow characteristics of mineral oils and crude oils.

1 . The use of (i) substituted ureas or urethanes of the general formula (I)
   R 1 X—CO—NR 3 R 4    (I)
   in which the variable X is R 2 N or O and the variables R 1  to R 4  are each independently hydrogen, C 1 - to C 30 -alkyl radicals which may be interrupted by one or more oxygen atoms, C 3 - to C 30 -alkenyl radicals, C 5 - to C 30 -cycloalkyl radicals, C 6 - to C 30 -aryl radicals or C 7 - to C 30 -arylalkyl radicals, where at least one of the variables R 1  to R 4  must be a radical having at least 4 carbon atoms and where one or more of the variables R 1  to R 4  may be a radical of the formula (Ia)
   -A-(X′—CO-A′) n -X′—CO—NR 6 R 7    (Ia)
 
   in which the variables A and A′ are each an aliphatic, cycloaliphatic, aromatic or aliphatic-aromatic bridging element having 1 to 20 carbon atoms, the variable X′ is NR 5  or O, the variable n is an integer from 0 to 50 and the variables R 5 , R 6  and R 7  are each independently hydrogen, C 1 - to C 30 -alkyl radicals which may be interrupted by one or more oxygen atoms, C 3 - to C 30 -alkenyl radicals, C 5 - to C 30 -cycloalkyl radicals, C 6 - to C 30 -aryl radicals or C 7 - to C 30 -arylalkyl radicals, where one or more of the variables R 5  to R 7  may be a radical having at least 4 carbon atoms,   for further improvement of the cold flow properties of mineral oils and crude oils which already comprise
 (ii) at least one further organic compound which is different than (i) and is suitable for dispersion or for promoting dispersion of paraffin crystals which precipitate under cold conditions and 
 (iii) at least one organic compound which is different than (i) and (ii) and improves the cold flow characteristics of mineral oils and crude oils. 
   
     
     
         2 . The use of substituted ureas or urethanes of the general formula (I) according to  claim 1 , in which the variables R 1  to R 4  are each independently hydrogen, C 1 - to C 30 -alkyl radicals which may be interrupted by one or more oxygen atoms, C 3 - to C 30 -alkenyl radicals, C 5 - to C 30 -cycloalkyl radicals, C 6 - to C 30 -aryl radicals or C 7 - to C 30 -arylalkyl radicals, where at least one of the variables R 1  to R 4  must be a radical having at least 4 carbon atoms. 
     
     
         3 . The use of substituted ureas or urethanes of the general formula (I) according to  claim 2 , in which the variables R 1  and R 3  are each hydrogen and the variables R 2  and R 4  are each the same C 4 - to C 30 -alkyl radical which may be interrupted by one or more oxygen atoms, C 4 - to C 30 -alkenyl radical, C 5 - to C 30 -cycloalkyl radical, C 6 - to C 30 -aryl radical or C 7 - to C 30 -arylalkyl radical. 
     
     
         4 . The use of substituted ureas or urethanes of the general formula (I) according to  claim 2 , in which the variables R 1  to R 4  are each the same C 4 - to C 30 -alkyl radical which may be interrupted by one or more oxygen atoms, C 4 - to C 30 -alkenyl radical, C 5 - to C 30 -cycloalkyl radical, C 6 - to C 30 -aryl radical or C 7 - to C 30 -arylalkyl radical. 
     
     
         5 . The use of substituted ureas or urethanes of the general formula (I) according to  claim 1 , in which the variables R 1  to R 4  are each independently hydrogen, C 1 - to C 30 -alkyl radicals which may be interrupted by one or more oxygen atoms, C 3 - to C 30 -alkenyl radicals, C 5 - to C 30 -cycloalkyl radicals, C 6 - to C 30 -aryl radicals or C 7 - to C 30 -arylalkyl radicals, where at least one of the variables R 1  to R 4  must be a radical having at least 4 carbon atoms, and where at least one other of the variables R 1  to R 4  must be a radical of the formula (Ia) in which the variables A and A′ are each an aliphatic, cycloaliphatic, aromatic or aliphatic-aromatic bridging element having 1 to 20 carbon atoms and the variables R 5 , R 6  and R 7  are each independently hydrogen, C 1 - to C 30 -alkyl radicals which may be interrupted by one or more oxygen atoms, C 3 - to C 30 -alkenyl radicals, C 5 - to C 30 -cycloalkyl radicals, C 6 - to C 30 -aryl radicals or C 7 - to C 30 -arylalkyl radicals, where one or more of the variables R 5  to R 7  may be a radical having at least 4 carbon atoms. 
     
     
         6 . The use of substituted ureas or urethanes of the general formula (I) according to  claim 1  or  5 , in which the variable A in the formula (Ia) is 3,5,5-trimethylcyclohexan-1-ylene-3-methylene, 1,6-hexamethylene, 2,4-tolylene, 2,6-tolylene, dicyclohexylmethan-4,4′-ylene or diphenylmethan-4,4′-ylene. 
     
     
         7 . The use of substituted ureas or urethanes of the general formula (I) according to  claim 5  or  6 , in which the variable X is R 2 N where R 2  is a radical of the formula (Ia) in which the variable n is 0, the variables R 1 , R 3 , R 5  and R 7  are each hydrogen and the variables R 4  and R 6  are each the same C 4 - to C 30 -alkyl radical which may be interrupted by one or more oxygen atoms, C 4 - to C 30 -alkenyl radical, C 5 - to C 30 -cycloalkyl radical, C 6 - to C 30 -aryl radical or C 7 - to C 30 -arylalkyl radical. 
     
     
         8 . The use of substituted ureas or urethanes of the general formula (I) according to  claims 1  to  7 , wherein the mineral oils or crude oils comprise at least one polar nitrogen compound as component (ii). 
     
     
         9 . The use of substituted ureas or urethanes of the general formula (I) according to  claims 1  to  8 , wherein the mineral oils or crude oils comprise, as component (iii), at least one copolymer of a C 2 - to C 40 -olefin with at least one further ethylenically unsaturated monomer. 
     
     
         10 . A mixture comprising
 (i) 1 to 99% by weight of at least one substituted urea or substituted urethane of the general formula (I) according to  claims 1  to  7 ,   (ii) 1 to 50% by weight of at least one further organic compound which is different than (i) and is suitable for dispersion or for promoting dispersion of paraffin crystals which precipitate under cold conditions and   (iii) 1 to 99% by weight of at least one organic compound which is different than (i) and (ii) and improves the cold flow characteristics of mineral oils and crude oils,   
       where the sum of all components (i) to (iii) adds up to 100% by weight. 
     
     
         11 . A fuel, especially middle distillate fuel, comprising a mixture according to  claim 10 . 
     
     
         12 . The fuel according to  claim 11 , comprising, as further additives in amounts customary therefor, conductivity improvers, anticorrosion additives, lubricity additives, antioxidants, metal deactivators, antifoams, demulsifiers, detergents, cetane number improvers, solvents or diluents, dyes or fragrances or mixtures thereof. 
     
     
         13 . A fuel additive concentrate comprising 10 to 70% by weight, based on the total amount of the concentrate, of a mixture according to  claim 10 , dissolved in a hydrocarbon solvent. 
     
     
         14 . The fuel additive concentrate according to  claim 13 , comprising, as further additives in amounts customary therefor, conductivity improvers, anticorrosion additives, lubricity additives, antioxidants, metal deactivators, antifoams, demulsifiers, detergents, cetane number improvers, solvents or diluents, dyes or fragrances or mixtures thereof.