PROCESS FOR PREPARING ETHYL POLYMERS BY MEANS OF A ZIEGLER CATALYST SYSTEM

Finely divided ethene polymers are prepared by means of a Ziegler catalyst system composed of (1) a titanium-containing catalyst component obtained by precipitation in an organic liquid from (1.1) a solution of titanium tetrachloride in a hydrocarbon, (1.2) a solution of a certain organoaluminum compound in a hydrocarbon, and a catalyst component which contains (1.3) an alpha-monoalkene and (2) aluminum, wherein the (1) used has been precipitated at relatively low temperatures in an organic liquid which, at the precipitation temperature has a relatively high viscosity and comprises (a) a liquid hydrocarbon and (b), dissolved therein, relatively small amounts of polymer of an alpha-monoalkene, with the provisos that (i) for every gram-mole of the total amount of titanium tetrachloride used specific amounts of the organic liquid, of the organoaluminum compound and of the alpha-monoalkene are used and (ii) for every mole unit of the total amount of titanium tetrachloride used specific amounts are precipitated per minute and specific amounts of the alpha-monoalkene are introduced per minute.