One-pot process of preparing long chain branched polypropylene using C ₂-symmetric metallocene complex and a "T" reagent

A one-pot polymerization process to prepare isotactic polypropylene with a long chain branched structure (LCBPE) using a novel branching 'T' reagent was investigated. The effect of the p-(3-butenyl)styrene 'T' reagent and hydrogen concentration on catalyst activity and p-(3-butenyl)styrene in-corporation modes by varying reaction conditions was also studied. It was found that both branch density and branch length can be conveniently controlled by the p-(3-butenyl)-styrene 'T' reagent, higher concentration higher branch density, and lower branch length. The LCBPE polymer's molecular weight distribution stayed relatively narrow, which indicated a single site copolymerization with a clean chain transfer reaction.