Patent ID: 8142902

Claim:
An article comprising a substrate, said substrate extrusion coated with a composition comprising a polypropylene material comprising propylene and up to 15% of a comonomer, wherein said polypropylene material is produced in the presence of an unsupported or self-supported, asymmetric metallocene catalyst, wherein the polypropylene material satisfies the equation: Vicat B [° C.]>−3.96· C x [mol %]+86.85; wherein: a) Vicat B is the heat resistance, according to ISO 306 (50 N), of the polypropylene material; and b) C x is the comonomer content in said polypropylene material; and wherein the polypropylene material has a strain hardening index of at least 0.30 measured by a deformation rate of 1.00 s −1 at a temperature of 180° C., wherein the strain hardening index is defined as a slope of a logarithm to the basis 10 of the tensile stress growth function as a function of a logarithm to the basis 10 of the Hencky strain in the range of Hencky strains between 1 and 3.