VERFAHREN ZUR HERSTELLUNG UND VERFAHREN ZUR VERWENDUNG EINES STRÖMUNGSBESCHLEUNIGERS

The invention relates to process for the production of a drag reducing agent wherein a monomer or monomer mixture comprising one or more C4-C30 monoolefins, preferably C6-C20 monoolefins, is polymerized into an essentially non-crystalline, hydrocarbon-soluble, ultrahigh molecular weight drag reducing polymer in the presence of a polymerization catalyst system comprising a Group 4-6 (IUPAC 1990) transition metal compound and an organoaluminium compound. In order to obtain a shear force resistant drag reducing agent, said transition metal compound has been prepared by providing a support comprising an atomized complex of a magnesium halide and a monohydric C1-C4 alcohol and contacting the support with a halogenous titanium compound and a C6-C18 alkyl carboxylic acid ester under conditions which deposit the halogenous titanium compound on the support and cause transesterification between the monohydric C1-C4 alcohol and the C6-C18 alkyl carboxylic acid ester. The shear force resistance can further be improved by copolymerizing the C4-C30 monoolefin(s) with 0.0001-10%, based on of the weight of the C4-C30 monoolefin(s), of a polyunsaturated aliphatic hydrocarbon.