Process for preparing polyolefins

Claim 1

A process for preparing polyolefins comprising polymerizing ethylene or copolymerizing ethylene with minor amounts of alpha olefins using a catalyst consisting essentially of a titanium-containing solid and an organometallic compound selected from the group consisting of organoaluminum compounds of the general formula R 3 Al, R 2 AlX, RAlX 2 , R 2 AlOR, RAl (OR)X and R 3 Al 2 X 3 wherein R is alkyl or aryl and may be alike or different and X is halogen, and organozinc compounds of the general formula R 2 Zn wherein R is alkyl and may be alike or different, said titanium-containing solid consisting essentially of a reaction product obtained by copulverizing (1) a magnesium halide selected from the group consisting of magnesium fluoride, magnesium chloride, magnesium bromide and magnesium iodide and/or a manganese halide selected from the group consisting of manganese fluoride, manganese chloride, manganese bromide and manganese iodide, (2) an organohalide selected from the group consisting of aliphatic and alicyclic hydrocarbons having 1 to 20 carbon atoms and containing at least one halogen substituent, and aromatic hydrocarbons having 6 to 20 carbon atoms and containing at least one halogen substituent, and (3) a titanium compound selected from the group consisting of (i) tetravalent titanium compound represented by the general formula Ti(OR) n X a-n wherein R is an alkyl, alkenyl, aryl or aralkyl group having 1 to 20 carbon atoms, X is a halogen atom and n is a whole number of from 0 to 4, and (ii) trivalent titanium compound selected from the group consisting of titanium trihalides obtained by reducing titanium tetrahalide with hydrogen, aluminum, titanium or an organometallic compound, and trivalent titanium compounds obtained by reducing tetravalent titanium alkoxyhalides represented by the general formula Ti(OR) n X 4-n wherein R is an alkyl, alkenyl, aryl or aralkyl having 1 to 20 carbon atoms, X is a halogen atom and n is a whole numberof from 1 to 4, with an organometallic compound of a metal of the groups I to III of the Periodic Table, wherein the weight ratio of the magnesium halide and/or manganese halide to the organohalide is in the range of from 1:0.5 to 1:0.01.