Patent ID: 8153745

Claim:
Polypropylene having a multi-branching index (MBI) of at least 0.15, wherein the multi-branching index (MBI) is defined as the slope of strain hardening index (SHI) as a function of the logarithm to the base 10 of the Hencky strain rate (lg(dε/dt)), wherein dε/dt is the deformation rate, ε is the Hencky strain, and the strain hardening index (SHI) is measured at 180° C., wherein the strain hardening index (SHI) is defined as the slope of the logarithm to the base 10 of the tensile stress growth function (lg(η E + )) as a function of the logarithm to the base 10 of the Hencky strain (lg(ε)) in the range of Hencky strains between 1 and 3, wherein the polypropylene has been produced in the presence of a catalyst system comprising an asymmetric non-silica supported catalyst, and wherein the polypropylene has a strain hardening index (SHI@1 s −1 ) of at least 0.40 measured by a deformation rate (dε/dt) of 1.00 s −1 at a temperature of 180° C.