Patent ID: 7851395

Claim:
A method for activating a Ziegler-Natta pre-catalyst component comprising: providing a finished Ziegler-Natta pre-catalyst component, wherein the Ziegler-Natta pre-catalyst component comprises magnesium, titanium, an amount of chlorine sufficient to fully chlorinate Mg and Ti to form MgCl 2 and TiCl 4 and internal electron donor(s) that comprise at least two distinct oxygen-containing functions; submitting the pre-catalyst to a thermal treatment carried out at a temperature of from 80 to 150° C. under vacuum of about 10 −10 bars; treating the pre-catalyst by adding a Lewis acid MX 4 soluble in apolar solvents wherein M is Si or Sn and wherein X is halogen or alkyl group; optionally further treating the Ziegler-Natta pre-catalyst component with a titanium compound TiX 4 before or after treating; adding aluminum compound of general formula AlR n Z 3-n wherein R is alkyl group having from 1 to 10 carbon atoms, Z is halogen and n is 0, 1, 2 or 3; and optionally adding an external electron donor either of general formula SiR a m (OR b ) 4-m or of general formula R′O—(CH2-CR 1 R 2 —CH2)-OR′ wherein R a and R b are each independently selected from alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl having at most 12 carbon atoms, and two neighbouring R can be linked together to make a ring, m is 0 or an integer from 1 to 4, wherein each R′, R 1 and R 2 are each independently selected from alkyl, aryl, cycloalkyl, arylalkyl or alkylaryl having at most 12 carbon atoms, and R 1 and R 2 can be linked together to make a ring or rings.