abstract |
Ethene polymers are prepared by Phillips catalysis using (1) a supported catalyst which is loaded with chromium and titanium and (2) a co-catalyst, (1) having been obtained by preparing (1.1) a chromium- and titanium-loaded catalyst intermediate from (1.1.a) a silicate carrier material, (1.1.b) a selected chromium compound and (1.1.c) a selected titanium compound and then (1.2) heating said catalyst intermediate in an oxygen-containing gas stream, the (1) used having been obtained by, in general terms, (1.1) preparing in the first stage (1.1.1) a suspension from (1.1.1.1) a finely divided silicate carrier material and (1.1.1.2) a liquid alkane, (1.1.2) then (1.1.2.1) combining the suspension resulting from (1.1.1.) with (1.1.2.2.) a finely divided chromium trioxide, (1.1.3) thereupon (1.1.3.1) combining the suspension obtained from (1.1.2) with (1.1.3.2) an alkanol, (1.1.4) thereafter (1.1.4.1) combining the suspension formed in (1.1.3) with (1.1.4.2) a titanium compound of the formula Ti(OR)4, where R is alkyl, aryl or cycloalkyl, and (1.1.5) finally evaporating the suspension obtained in (1.1.4) to dryness, and then (1.2) in the second stage first (1.2.1) treating the catalyst intermediate obtained in the first state (1.1) with a nitrogen stream, thereupon (1.2.2) heating the intermediate obtained in (1.2.1) in an oxygen-containing gas stream, and finally (1.2.3) treating the intermediate obtained in (1.2.2) with a nitrogen stream; and as (2) with an alkyllithium. |