New copolymers, mixtures thereof with poly(meth)acrylate esters and the use thereof for improving the cold fluidity of crude oils

A mixture of:

• a) 10 to 90% by weight of a copolymer consisting of 50 to 99.9% by weight of only one C.sub.14 -C.sub.22 -alkyl methacrylate or only one C.sub.14 -C.sub.22 -alkyl acrylate and 50 to 0.1% by weight of only one comonomer selected from the group consisting of comonomers of the formula I ##STR15## in which R.sub.1 is hydrogen or methyl, R.sub.2 is a group of the formulae ##STR16## R.sub.3 is C.sub.1 -C.sub.80 -alkyl, C.sub.6 -C.sub.36 -alkenyl, C.sub.5 - or C.sub.6 -cycloalkyl or -cycloalkenyl which can each be substituted by alkyl groups, or is aralkyl, alkaryl or the radical of a dimeric fatty acid, or maleic acid, or succinic acid or of a C.sub.6 -C.sub.22 -alkenylsuccinic acid, R.sub.4 is C.sub.1 -C.sub.80 -alkyl, C.sub.1 -C.sub.80 -alkenyl, C.sub.5 - or C.sub.6 -cycloalkyl or -cycloalkenyl which can each be substituted by alkyl groups, or is aryl, aralkyl or alkaryl,
• m is 2 or 3,
• n is a number from 1 to 30 and X is a number from 12 to 20, and;
• b) 90 to 10% by weight of a poly-C.sub.14 -C.sub.22 -alkyl methacrylate or poly-C.sub.14 -C.sub.22 -alkylacrylate.