Copolymerization of Propylene with Poly(ethylene-co-propylene) Macromonomer and Branch Chain-Length Dependence of Rheological Properties

A series of isotactic polypropylene (PP) samples with poly(ethylene-co-propylene) long chain branching were produced by a semibatch copolymerization of poly(ethylene-co-propylene) macromonomer (EPR), prepared in a high-temperature continuous stirred tank reactor (CSTR), and propylene using rac-dimethylsilylenebis(2-methylbenz[e]indenyl) zirconium dicholoride/modified methylaluminoxane. The branch frequency and branch length of the copolymers …