Cold flow improvers for vegetable or animal fuel oils

摘要

The present invention relates to a fuel oil additive comprising A) a copolymer of ethylene and from 18 to 35 mol % of at least one acrylic ester or vinyl ester having a C₁-C₁₈-alkyl radical and a degree of branching of less than 5 CH₃/100 CH₂ groups, and B) a comb polymer comprising structural units formed from B1) at least one olefin as monomer 1, which bears at least one C₈-C₁₈-alkyl radical on the olefinic double bond, and B2) at least one ethylenically unsaturated dicarboxylic acid as monomer 2, which bears at least one C₈-C₁₆-alkyl radical bonded via an amide and/or imide group, in which the parameter Q $Q=\sum _iw_{1i}.n_{1i}+\sum _jw_{2j}.n_{2j}$ in which w₁ is the molar proportion of the individual chain lengths n, in the alkyl radicals of monomer 1, w₂ is the molar proportion of the individual chain lengths n₂ in the alkyl radicals of the amide and/or imide groups of monomer 2, n₁ are the individual chain lengths in the alkyl radicals of monomer 1, n₂ are the individual chain lengths in the alkyl radicals of the amide and/or imide groups of monomer 2, i is the serial variable for the chain lengths in the alkyl radicals of monomer 1, and is the serial variable for the chain lengths in the alkyl radicals of the amide and/or imide groups of monomer 2 assumes values of from 23 to 27.