In-reactor stabilization of polypropene

Propene was polymerized with a high activity, high stereospecific supported Ziegler-Natta catalyst in presence of phenolic antioxidants (AO), phosphite processing stabilizers (PS) or sterically hindered amine stabilizers (HAS).PS and some HAS grades did not influence propene polymerization, but AO and most commercial HAS could interfere with the catalyst and reduce catalyst activity.