Process for producing stereoregular polymers having a narrow molecular weight distribution

Abstract From the Canadian patent

Stereoregular polymers having a molecular weight distribution of less than 5.0 and an isotactic index in excess of 96 percent are produced by polymerizing an alpha-olefin having 3 to B carbon atoms in a low pressure gas phase fluid bed process at a temperature in excess of 80°C employing a heat stable catalyst system comprising (a) a solid catalyst component containing magnesium titanium, halide and a polycarboxylic acid ester containing two coplanar ester groups attached to adjacent carbon atoms, as inside electron donor (b) an, organoaluminum cocatalyst, and (c) a silicon compound containing a silicon-oxygen-carbon linkage as out-, side electron donor.