| abstract |
AND (3) COCATALYTIC AMOUNTS OF AN ALKYL ALUMINUM COMPOUND OF THE FORMULA RaAlXb, in each of which formula R is a hydrocarbon radical containing from 1 to about 14 carbon atoms, X is hydrogen, halogen or alkoxy, a is an integer of 1-3, b is an integer of 0-2 and the sum of a and b is 3. The disclosure also includes methods of polymerizing at least one such olefin which comprises contacting the olefin under polymerizing conditions with the above catalyst system. The disclosure also includes methods of making the catalyst system. A catalyst system for the polymerization of at least one 1olefin comprising a mixture of (1) a support which is a finely divided insoluble inorganic support material such as silica, alumina, zirconia or thoria or mixtures thereof containing titanium, zirconium or nickel prepared by fluidizing the finely divided support in the form of a bed with a substantially dry gas while adding to the bed at an elevated temperature, while fluidizing, a compound of the class consisting of titanium or zirconium or nickel esters, or halides or mixtures thereof which were further calcined at a higher temperature and (2) an organotin chromate containing the group essentially of the formula |