Ethylene-based copolymers and their use as flow improvers in mineral oil middle distillates

摘要

Ethylene-based copolymers which are suitable as flow improvers for mineral oil middle distillates are composed of a) from 50 to 94% by weight of ethylene, b) from 3 to 30% by weight of one or more vinyl esters of C2-C6-monocarboxylic acids, c) from 3 to 20% by weight of one or more aminoalkyl acrylates of the general formula I <IMAGE> (I) where R1 is hydrogen or methyl, R2 and R3 may be identical or different and are each hydrogen or C1-C6-alkyl and A1 is straight-chain or branched C2-C10-alkylene, and d) from 0 to 10% by weight of one or more monomers which are copolymerizable with the monomers a) to c), copolymers in which monomer b) is vinyl acetate and which have a number average molecular weight of from 5000 to 50,000 being excluded, or are composed of a') from 50 to 95.5% by weight of ethylene, b') from 4 to 30% by weight of one or more vinyl esters of C2-C6-monocarboxylic acids, c') from 0.5 to 20% by weight of one or more vinylimidazoles of the general formula II <IMAGE> (II) where R4, R5 and R6 may be identical or different and are each hydrogen or C1-C6-alkyl, or from 0.5 to 20% by weight of one or more aminoalkyl vinyl ethers of the general formula IIIR7R8N-A2-O-CR9=CR10R11(III)where R7 and R8 are each C1-C6-alkyl, R9, R10 and R11 are each hydrogen or C1-C6-alkyl and A2 is C2-C6-alkylene, and d') from 0 to 10% by weight of one or more monomers which are copolymerizable with the monomers a') to c').