Patent ID: 6867160

Claim:
A process for preparing an olefin polymerization catalyst comprising sequentially mixing: (i) a solution of a mixture of a compound of the formula (R 1 ) 2 Mg wherein R 1 is selected from the group consisting of C 1-6 alkyl radicals and a compound of the formula Al 1 (R 2 ) 3 wherein R 2 is selected from the group consisting of C 1-6 alkyl radicals; with (ii) a solution of HCl or an organic chloride of the formula R 3 Cl wherein R 3 is selected from the group consisting of C 1-6 alkyl radicals and C 6-12 aromatic radicals; and maintaining the resulting mixture at a temperature from 30° C. to 40° C. for a period from 10 to 40 seconds; then (iii) rapidly adding a solution of a titanium compound of the formula (R 4 ) a TiCl b-a wherein R 4 is a C 1-6 alkoxy radical and a and b are 0 or integers from 1 to 4 and the sum of a+b is 4 to provide a molar ratio of Mg:Al 1 from 3:1 to 8:1; a molar ratio of Cl:Mg from 1.5:1 to 2.5:1; molar ratio of Al 1 :Ti from 0.5:1 to 1.5:1; and a molar ratio of Mg:Ti from 3:1 to 8:1 and in less than 20 seconds bringing temperature of the resulting mixture to from 130° C. to 160° C. by any of: a) heating one of the mixture of component (ii) and the solution of the titanium compound or both to a temperature sufficient so that upon mixing said temperature is obtained within 20 seconds; or b) heating one of the mixture of step (ii) and the solution of titanium compound or both to a temperature insufficient so that upon mixing said temperature is not obtained and heating the resulting mixture at a rate to obtain said temperature within 20 seconds; and combining the resulting hot mixture with (iv) a compound of the formula (R 5 ) 2 Al 2 (R 6 ) wherein R 5 is a C 1-6 alkyl radical and R 6 is a C 1-6 alkoxy radical to provide a molar ratio of Al 2 to Ti from 0.5:1 to 1.5:1.