Catalyst components for the polymerization of olefins

摘要

A porous solid catalyst component comprising a magnesium halide, a titanium compound having at least a Ti-halogen bond and at least two electron donor compounds one of which being selected from 1,3-diethers and the other being selected from succinates, characterized by the fact that the molar ratio ID/Ti is from 0.30 to 0.90, where ID is the total molar amount of succinate and 1,3-diether, the molar ratio of the 1,3-diether donor to the succinate donor is higher than, or equal to, 0.60.

主权项

1. A catalyst system comprising:
(A) a solid catalyst component comprising:
(i) a magnesium halide,(ii) TiCl4,(iii) a first internal electron donor, and(iii) a second internal electron donor,wherein the first internal electron donor compound is a 1,3-diether, and wherein the second internal electron donor is a succinate;wherein the first internal electron donor and the second internal electron donor have an internal electron donor molar ratio from 0.80-1.80, and the ratio of the total amount of the first and second internal electron donors to Ti is from 0.45-0.75; andwherein the solid catalyst component has a porosity of greater than 0.40 cm3/g, based upon pores with a radius equal to or less than 1 μm present in the solid catalyst component; (B) an alkylaluminum cocatalyst compound; and (C) an external electron donor compound selected from silicon compounds of formula Ra5Rb6Si(OR7)c, where a and b are integers from 0 to 2, c is an integer from 1 to 4 and the sum (a+b+c) is 4; R5, R6 and R7 are alkyl, cycloalkyl or aryl radicals with 1-18 carbon atoms optionally containing heteroatoms.