High stiffness polypropylene impact copolymer

An impact copolymer with a MFR within a range from 60 g/10 min to 140 g/10 min (230° C., 2.16 kg) consisting essentially of a homopolypropylene and within a range from 4 wt % to 10 wt % of an ethylene-propylene copolymer (EPR) by weight of the impact copolymer;

• wherein the homopolypropylene has a MFR within a range from 80 g/10 min to 200 g/10 min (230° C., 2.16 kg), an Mw/Mn within a range from 8 to 15, an Mz/Mw within a range from 7 to 16, and comprising 1.1 wt % or less atactic polypropylene based on the total weight of the homopolypropylene and atactic polypropylene;
• and the EPR has within a range from 30 wt % to 50 wt % ethylene derived units by weight of the EPR, and an intrinsic viscosity within a range from 4 to 7 dL/g;
• and the impact copolymer is obtained by combining a Ziegler-Natta catalyst with propylene in two slurry polymerization reactors in series to produce the homopolypropylene, followed by combining the homopolypropylene and Ziegler-Natta catalyst with propylene and ethylene in a gas phase reactor to produce the EPR that is linked to the homopolypropylene, where the Ziegler-Natta catalyst comprises to different internal electron donors wherein the propylene-α-olefin copolymer comprises within a range from 30 wt % to 43 wt % α-olefin derived units by weight of the propylene-α-olefin copolymer.